Kofi
2011-08-20 05:29:10 UTC
Cathelicidin is deficient in atopic dermatitis and vitamin D in
sinusitis. The inability to defend against staph leads to the
production of staph toxins/superantigens in both sinusitis and atopic
dermatitis and this appears to drive the overexpression of NGF, which is
associated in other contexts with scarring conditions like nasal polyps
in chronic rhinitis/sinusitis and keloids. Mast cells are deeply
involved in this process.
Allergy Asthma Immunol Res. 2010 Oct;2(4):235-46. Epub 2010 May 12.
A Role of Staphyococcus aureus, Interleukin-18, Nerve Growth Factor and
Semaphorin 3A, an Axon Guidance Molecule, in Pathogenesis and Treatment
of Atopic Dermatitis.
Ikezawa Z, Komori J, Ikezawa Y, Inoue Y, Kirino M, Katsuyama M, Aihara M.
Department of Environmental Immuno-Dermatology, Yokohama City University
Graduate School of Medicine, Yokohama, Japan.
Staphylococcus aureus (SA) is usually present not only in the skin
lesions of atopic dermatitis (AD) but also in the atopic dry skin. SA
discharges various toxins and enzymes that injure the skin, results in
activation of epidermal keratinocytes, which produce and release IL-18.
IL-18 that induces the super Th1 cells secreting IFN-gamma and IL-13 is
supposed to be involved in development of AD and its pathogenesis.
Indeed, the number of SA colonies on the skin surface and the serum
IL-18 levels in patients with AD significantly correlated with the skin
scores of AD lesions. Also, there is strong positive correlation between
the skin scores and serum IL-18 levels in DS-Nh mice (P<0.0001, r=0.64),
which develop considerable AD-like legions when they are housed under
conventional conditions, but develop skin legions with less severity and
less frequency under specific pathogens free (SPF) conditions.
Therefore, they are well-known as model mice of AD, in which SA is
presumed to be critical factor for the development of AD lesions. Also,
theses DS-Nh mice pretreated with Cy developed more remarkable AD-like
lesions in comparison with non-treated ones. The levels of INF-r and
IL-13 in the supernatants of the lymph node cell cultures stimulated
with staphylococcal enterotoxin B (SEB) or ConA were increased in the
Cy-treated mice, although the serum levels of total IgE were not. In
this experiment, we revealed that Cy-treated mice, to which CD25+CD4+
regulatory T cells taken from non-treated ones had been transferred,
developed the AD-like legions with less severity and less number of SA
colonies on the skin surface. Therefore, it is presumed that CD25 +CD4 +
regulatory T cells might be involved in the suppression of super Th1
cells which are induced by IL-18 and are involved in the development of
AD-like lesions rather than IgE production. The efficient induction of
CD25+CD4+ regulatory T cells is expected for the new type of treatment
of AD. We also found that farnesol (F) and xylitol (X) synergistically
inhibited biofilm formation by SA, and indeed the ratio of SA in total
bacteria at sites to which the FX cream containing F and X had been
applied was significantly decreased 1 week later, accompanied with
improvement of AD, when compared with that before application and at
placebo sites. Therefore, the FX cream is a useful skin-care agent for
atopic dry skin colonized by SA. The nerve growth factor (NGF) in the
horny layer (the horn NGF) of skin lesions on the cubital fossa was
collected by tape stripping and measured using ELISA in AD patients
before and after 2 and 4 weeks treatments. Simultaneously, the itch and
eruptions on the whole body and on the lesions, in which the horn NGF
was measured, were recorded, and also the peripheral blood eosinophil
count, serum LDH level and serum total IgE level were examined. The
level of NGF was significantly higher in AD patients than in healthy
controls, correlated with the severity of itch, erythema, scale/xerosis,
the eosinophil count and LDH level, and also significantly decreased
after treatments with olopatadine and/or steroid ointment for 2 and 4
weeks. Therefore, the measurement of the NGF by this harmless method
seems to be useful to assess the severity of AD and the therapeutic
effects on AD. In AD patients, C-fiber in the epidermis increase and
sprout, inducing hypersensitivity, which is considered to aggravate the
disease. Semaphorin 3A (Sema3A), an axon guidance molecule, is a potent
inhibitor of neurite outgrowth of sensory neurons. We administered
recombinant Sema3A intracutaneously into the skin lesions of NC/Nga
mice, an animal model of AD, and investigated the effect of Sema3A on
the skin lesions and their itch. Sema3A dose-dependently improved skin
lesions and attenuated the scratching behavior in NC/Nga mice.
Histological examinations revealed a decrease in the epidermal
thickness, the density of invasive nerve fibers in the epidermis,
inflammatory infiltrate including mast cells and CD4 +T cells, and the
production of IL-4 in the Sema3A-treated lesions. Because the
interruption of the itch-scratch cycle likely contributes to the
improvement of the AD-like lesions, Sema3A is expected to become a
promising treatment of patients with refractory AD.
PMID: 20885908
Am J Rhinol Allergy. 2009 Nov-Dec;23(6):571-4.
Mucosal expression of nerve growth factor and brain-derived neurotrophic
factor in chronic rhinosinusitis.
Coffey CS, Mulligan RM, Schlosser RJ.
The Medical University of South Carolina, Department of
Otolaryngology/Head & Neck Surgery, Charleston, South Carolina 29425,
USA.
BACKGROUND: Allergic rhinitis (AR) is characterized in part by
hyperresponsiveness to nonspecific stimuli, a phenomenon that reflects
the fundamental role of nasal neural pathways in chronic airway
inflammation. Neurotrophins may serve pivotal roles in mediating
hyperresponsiveness in allergic airway disease, although the role of
such neurogenic mediators in chronic rhinosinusitis (CRS) is not well
understood. This study was designed to examine the expression of two
potent neurotrophins, nerve growth factor (NGF) and brain-derived
neurotrophic factor (BDNF), in CRS. METHODS: Inferior turbinate and
sinus mucosa were obtained from CRS patients with and without nasal
polyps (NPs) and from nonallergic controls. Enzyme-linked immunosorbent
assay was used for quantitative determination of tissue concentrations
of NGF and BDNF. RESULTS: Ninety-four tissue samples from 48 patients
were included. Mean concentration of NGF in sinus mucosa was
significantly higher in CRS than controls. CRS without NPs was
associated with a 60% increase in sinus NGF over controls (p < 0.05),
and CRS with NPs was associated with a 140% increase (p < 0.05). Mean
sinus NGF concentration was significantly elevated in allergic subjects
compared with controls (p < 0.01). A similar trend was noted in subjects
with nonallergic CRS, although this did not reach significance. Mean
BDNF concentration was decreased in CRS compared with controls, with the
most significant decrease in patients with polyps (p < 0.05). Mean
turbinate concentration of both NGF and BDNF were similar in controls
and CRS. CONCLUSION: Increased expression of NGF may contribute to
neural hyperresponsiveness in CRS sinus mucosa, particularly those
patients with NP and/or allergies. BDNF expression is decreased in CRS
sinus mucosa. Alterations in neurogenic inflammation may contribute to
the pathophysiology of CRS and provide alternative therapeutic targets.
Publication Types:
* Research Support, Non-U.S. Gov't
PMID: 19958603
39 chronic sinusitis patients had a number of familiar characteristics:
1) three fourths had sinusitis for more than 6 years, 2) about
two-thirds said they had "symptoms all the time", 3) 21/39 patients had
asthma, 4) 23/39 had nasal polyps, 5) 6/39 patients had aspirin
sensitivity; The patients were tested for biofilms, then underwent FESS
surgery. They were assessed before and up to 12 months after surgery
through various scoring systems. The first finding is that 30 out of 39
patients were found to have biofilms, with a majority of patients having
biofilms composed of multiple germs. More than half of those biofilms
included staph, either as the only germ or as one of several. Other
germs found either alone or in combination in the biofilms were
Pseudomonas, Haemophilus influenzae, and fungi. They also cultured
bacteria from intraoperative swabs and found a good number of staph, but
also other species. One interesting finding is that "There was no
correlation between the bacteria isolated via culture and the
species-specific biofilm identified via FISH, in keeping with the
biofilm hypothesis of biofilm bacteria not being culturable via the
conventional techniques." The main finding is that patients with
polymicrobial biofilms, especially with staph, or unimicrobial biofilms
with staph, had worse surgery outcomes than other patients at 12 months.
The authors conclude that a likely explanation for the aggravating role
of staph is that they produce superantigens which in turn elicit an
immune response biaised towards Th2, but that the germs in the biofilm
are protected from this immune response by the biofilm matrix. This
inefficient immune response creates local damage, however, which
severely increases inflammation. <doi: 10.1002/lary.21805>, abstract:
Chronic rhinosinusitis (CRS) patients with biofilms have persistent
postoperative symptoms, ongoing mucosal inflammation, and recurrent
infections. Recent evidence suggests that biofilms of differing species
confer varying disease profiles in CRS patients. We aimed to
prospectively investigate the effects of Staphylococcus aureus,
Pseudomonas aeruginosa, Haemophilus influenzae, and fungal biofilms on
outcomes following endoscopic sinus surgery (ESS). STUDY DESIGN:
Prospective blinded study. METHODS: In this prospective blinded study,
39 patients undergoing ESS for CRS assessed their symptoms
preoperatively using internationally accepted standardized symptom
scoring systems and quality-of-life measures (10-point visual analog
scale, Sino-Nasal Outcome Test-20, global severity of CRS). Their
sinonasal mucosa was graded (Lund-Kennedy scale) and extent of
radiologic disease on computed tomography scans scored (Lund-McKay
scale). Random sinonasal tissue samples were assessed for different
bacterial species forming biofilms by using fluorescent in-situ
hybridization and confocal laser microscopy. For 12 months after
surgery, CRS symptoms, quality of life, and objective evidence of
persisting disease were assessed by using the preoperative tools.
RESULTS: Different bacterial species combinations were found in 30 of 39
patients; 60% of these 30 biofilms were polymicrobial biofilms and 70%
had S aureus biofilms. Preoperative nasendoscopy and radiologic disease
severity were significantly worse in patients with multiple biofilms (P
= .02 and P = .01, respectively), and they had worse postsurgery mucosal
outcomes on endoscopy (P = .01) requiring significantly more
postoperative visits (P = .04). Those with S aureus biofilms progressed
poorly with their symptom scores and quality-of-life outcomes, with
significant differences in nasendoscopy scores (P = .007). CONCLUSIONS:
S. aureus biofilms play a dominant role in negatively affecting outcomes
of ESS with persisting postoperative symptoms, ongoing mucosal
inflammation, and infections [PMID 21647904]
Chronic rhinosinusitis with nasal polyps often represents a chronic
severe inflammatory disease of the upper airways and may serve as a
model for lower airway diseases such as late-onset intrinsic asthma.
Enterotoxins derived from Staphylococcus aureus have been implicated in
the pathophysiology of nasal polyps as disease-modifying factors; recent
findings using therapeutic proof-of-concept approaches support this
hypothesis. RECENT FINDINGS: Nasal polyps (chronic rhinosinusitis with
nasal polyps) are characterized by a T-helper-2 (Th2) dominated cytokine
pattern that includes interleukin-5 and formation of immunoglobulin E
(IgE). This is in contrast to chronic rhinosinusitis without polyps,
which exhibits T-helper-1 biased cytokine release. It is now evident
that the cytokine environment is decisive regarding the impact of S.
aureus derived enterotoxins, which function as superantigens. S. aureus
enterotoxin B further shifts the cytokine pattern in nasal polyps toward
T-helper-2 cytokines (increases greater than twofold for interleukin-2,
interleukin-4 and interleukin-5), but it disfavours the T-regulatory
cytokines interleukin-10 (IL-10) and transforming growth factor-beta1.
Furthermore, S. aureus derived enterotoxins influence local
immunoglobulin synthesis and induce polyclonal immunoglobulin E
production, which may contribute to severe inflammation via activation
of mast cells. SUMMARY: From this new understanding of chronic
rhinosinusitis with nasal polyps, new therapeutic approaches emerge such
as anti-interleukin-5, anti-immunoglobulin E, and antibiotic treatment.
These may enlarge the nonsurgical armentarium [PMID 18188015], ³Role of
staphylococcal superantigens in upper airway disease²
The effect of staphylococcal superantigens (SsAgs) on cutaneous
lymphocyte-associated antigen (CLA)(+) CD4(+) Foxp3(+) T cells of atopic
dermatitis (AD) patients is unknown. OBJECTIVE: To compare the effects
of SsAgs on the ratio, function, and apoptosis of CCR6(+) subtype and
CCR6(-) subtype of CLA(+) CD4(+) Foxp3(+) T cells among AD patients,
asthma/allergic rhinitis (AR) patients without AD, and healthy subjects.
METHODS: Using immunofluorescence staining followed by flow cytometric
analysis, we analysed peripheral blood mononuclear cells cultured with
or without staphylococcal enterotoxin B (SEB) stimulation in 20 AD
patients, 20 asthma/AR patients without AD, and 20 healthy subjects.
RESULTS: SEB decreased CCR6(+) /CCR6(-) ratio in CLA(+) CD4(+) Foxp3(+)
T cells from AD patients and increased CCR6(+) /CCR6(-) ratio in those
from healthy subjects. SEB induced the production of type 2 T helper
cell (Th2) cytokine interleukin (IL)-5 in CCR6(-) subtype and
anti-inflammatory cytokine IL-10 in CCR6(+) subtype of CLA(+) CD4(+)
Foxp3(+) T cells. CLA(+) CD4(+) Foxp3(+) T cells from AD patients
produced more IL-5 and less IL-10 after SEB stimulation than those from
healthy subjects. CCR6(-) subtype of CLA(+) CD4(+) Foxp3(+) T cells from
AD patients and CCR6(+) subtype of those cells from healthy subjects
were more resistant to SEB-induced caspase-3 activation than the other
subtype and those from other subjects. CONCLUSIONS AND CLINICAL
RELEVANCE: Despite a phenotype of regulatory T cells, skin-homing CD4(+)
Foxp3(+) T cells of AD patients exert effector Th2-like function after
SsAgs stimulation, which may aggravate allergic skin inflammation [PMID
21255144]
Toxic shock syndrome (TSS) is an acute, serious systemic illness caused
by bacterial superantigens. Nonavailability of a suitable animal model
until recently has hampered an in-depth understanding of the
pathogenesis of TSS. In the current study, we characterized the early
molecular events underlying TSS using our HLA-DR3 transgenic mouse
model. Gene expression profiling using DNA microarrays identified a
rapid and significant upregulation of several pro- as well as
anti-inflammatory mediators, many of which have never been previously
described in TSS. In vivo administration of staphylococcal enterotoxin B
(SEB) led to an increase in the expression of Th0- (IL-2, 240-fold);
Th1- (IFN-gamma, 360-fold; IL-12, 8-fold); Th2- (IL-4, 53-fold; IL-5,
4-fold) as well as Th17-type cytokines (IL-21, 19-fold; IL-17, 5-fold).
The immunoregulatory cytokines (IL-6, 700-fold; IL-10, 18-fold); CC
chemokines (such as CCL 2, 11, 3, 24, 17, 12, 7), CXC chemokines (such
as CXCL 1, 2, 5, 11, 10, 19); and several proteases (matrix
metalloproteinases 13, 8, 3, and 9) were also upregulated. Serum levels
of several of these cytokines/chemokines were also significantly
elevated. Pathway analyses revealed significant modulation in a variety
of biochemical and cellular functions, providing molecular insights into
the pathogenesis of TSS. Administration of bortezomib, a clinically
approved proteasome inhibitor capable of blocking NF-kappaB pathway, was
able to significantly modulate the expression of a variety of genes
induced by SEB. Thus, our study showed that TSS is a complex process and
emphasized the potential of use of bortezomib in the therapy of
superantigen-induced TSS [PMID 19336531]
It is unresolved whether circulating CD25hiCD4+ T cells in patients with
atopic dermatitis who have elevated IgE (IgE(high)) are regulatory or
effector in nature. OBJECTIVE: To analyze the properties of CD25hi
T-cell subtypes in IgE(high) atopic dermatitis. METHODS: The phenotype
of circulating CD25hi T cells was analyzed by flow cytometry using PBMCs
from patients with atopic dermatitis (total IgE > 250 IU/mL). Cytokines
induced in CD25hi subtypes were analyzed after activation with anti-CD3
mAb (+/-IL-2) and in the presence of activated autologous effector T
cells (CD25negCD4+). Reactivity to bacterial superantigen derived from
the skin-colonizing organism Staphylococcus aureus was also evaluated.
RESULTS: CD25(hi) T cells expressing regulatory T-cell markers (Foxp3,
CCR4, cutaneous lymphocyte-associated antigen) were increased in atopic
dermatitis compared with IgE(low) controls. This phenomenon was linked
to disease severity. Two subtypes of CD25hi T cells were identified on
the basis of differential expression of the chemokine receptor CCR6.
Although the ratio of CCR6+ and CCR6neg subtypes within the CD25hi
subset was unaltered in atopic dermatitis, each subtype proliferated
spontaneously ex vivo, suggesting in vivo activation. Activated CCR6neg
cells secreted T(H)2 cytokines, and coculture with effector T cells
selectively enhanced IL-5 production. Moreover, induction of a
T(H)2-dominated cytokine profile on activation with bacterial
superantigen was restricted to the CCR6neg subtype. CONCLUSION: Despite
a regulatory phenotype, activated CD25hi T cells that lack expression of
CCR6 promote T(H)2 responses [PMID 18177697]
Several factors regulate nerve growth factor (NGF), which is formed from
proNGF by intracellular and extracellular enzymatic cleavage. The close
proximity between mast cells, expressing the protease tryptase, and
NGF-producing smooth-muscle-like peritubular cells in the testis of
infertile patients, led us to examine the question, whether tryptase is
among those factors. Human peritubular cells express functional
tryptase-receptors (PAR-2). Recombinant enzymatically active
beta-tryptase increased NGF levels in the culture medium of primary
human peritubular cells, but the peptide agonist for PAR-2 (SLIGKV) did
not. Neither tryptase, nor the peptide, increased NGF mRNA levels. To
test whether the increase in NGF is due to enzymatic activity of
tryptase, acting on proNGF, supernatants of peritubular cells and
synthetic proNGF were treated with tryptase. Results of Western blot
studies indicate enzymatic cleavage of proNGF by active tryptase.
Heat-inactivated tryptase or SLIGKV were not effective. Mass
spectrometry analysis of in vitro cleavage products from recombinant
tryptase and synthetic proNGF revealed multiple cleavage sites within
the proNGF sequence. The results also indicate the generation of mature
NGF and of smaller NGF fragments, as a result of tryptase action. Thus,
tryptase-secreting mast cells in the vicinity of proNGF/NGF-secreting
cells in any human tissue are likely able to alter the ratios of
proNGF/NGF. As NGF and proNGF have different affinities for their
receptors, this indicates a novel way, how mast cells, via tryptase, can
modify the microenvironment in human tissues with regard to neurotrophin
actions [PMID 21768088], ³Human tryptase cleaves pro-nerve growth factor
(PRONGF): hints of a local, mast cell-dependent regulation of NGF/PRONGF
action²
Cathelicidin dysfunction emerges as a central factor in the pathogenesis
of several cutaneous diseases, including atopic dermatitis, in which
cathelicidin is suppressed; rosacea, in which cathelicidin peptides are
abnormally processed to forms that induce inflammation; and psoriasis,
in which cathelicidin peptide converts self-DNA to a potent stimulus in
an autoinflammatory cascade [PMID 19720207]
involvement of HIF-1alpha & mast cells in keloid formation;; Keloids
represent a prolonged inflammatory fibrotic state with areas that
display distinctive histological features characterized by an abundant
extracellular matrix stroma, a local infiltration of inflammatory cells
including mast cells, and a milieu of enriched cytokines. Previous
studies from our laboratory demonstrated an intrinsic higher level of
HIF-1alpha and VEGF protein expression in keloid tissues compared with
their adjacent unremarkable skins. To further investigate the mechanisms
underlying the elevated expression of HIF-1alpha and VEGF in keloids, we
exposed a co-culture of keloid fibroblasts and mast cells (HMC-1) to
hypoxic conditions and studied the expression of HIF-1alpha and its
target gene, VEGF. Our results showed that hypoxia-dependent HIF-1alpha
protein accumulation and VEGF expression is augmented in keloid
fibroblasts when co-cultured with HMC-1 cells under the condition where
direct cell-cell contact is allowed. But such augmentation is not
observed in the transwell co-culture system whereas fibroblasts and
HMC-1 cells were separated by a porous membrane. Our results also
indicated that the enhancement of hypoxia-mediated activation of ERK1/2
and Akt requires direct cell-cell interaction between mast cells and
keloid fibroblasts, and activation of both ERK1/2 and Akt is involved in
the hypoxia-dependent HIF-1alpha protein accumulation and VEGF
expression in the co-culture system. These findings suggest that under
hypoxic conditions mast cells may contribute, at least in part, to an
elevated expression of HIF-1alpha and VEGF protein in keloids via direct
cell-cell interaction with fibroblasts [PMID 16289155]
Microarray analysis is a popular tool to investigate the function of
genes that are responsible for the phenotype of diseases. Keloid is an
intricate lesion that is probably modulated by interplay of many genes.
We ventured to study the differences of gene expressions between keloids
and normal skin with the aid of a cDNA microarray to explore the
molecular mechanism underlying keloid formation. MATERIALS AND METHODS:
The polymerase chain reaction products of 8400 human genes were spotted
on a chip in array. The DNAs were then fixed on the glass plate by a
series of treatments. Total RNAs were isolated from freshly excised
human keloids and normal skins and then were purified to mRNAs by
Oligotex. Both the mRNAs from keloids and normal skins were reversely
transcribed to cDNAs with the incorporation of fluorescent dUTP for
preparing the hybridization probes. The mixed probes were then
hybridized to the cDNA microarray. After highly stringent washing, the
cDNA microarray was scanned for the fluorescent signals to display the
differences between two kinds of tissues. RESULTS: Among 8400 human
genes, there were 402 genes (4.79%) with different expression levels
between the keloids and normal skins in all cases, 250 genes, including
TGF-beta1 and NGF, were upregulated (2.98%) and 152 downregulated
(1.81%). Analyses of collagen, fibronectin, proteoglycan, growth
factors, and apoptosis-related molecule gene expression confirmed that
our molecular data obtained by cDNA microarray were consistent with the
published biochemical and clinical observations of keloids. Higher
expression of TGF-beta(1) and NGF in keloids versus normal skins was
also testified with reverse transcription polymerase chain reaction
method. CONCLUSIONS: DNA microarray technology is an effective technique
in screening for differences in gene expression between keloid and
normal skin. Many genes are involved in the formation of keloids.
Further analysis of the obtained genes will help to understand the
molecular mechanism of keloid formation [PMID 12957131]
sinusitis. The inability to defend against staph leads to the
production of staph toxins/superantigens in both sinusitis and atopic
dermatitis and this appears to drive the overexpression of NGF, which is
associated in other contexts with scarring conditions like nasal polyps
in chronic rhinitis/sinusitis and keloids. Mast cells are deeply
involved in this process.
Allergy Asthma Immunol Res. 2010 Oct;2(4):235-46. Epub 2010 May 12.
A Role of Staphyococcus aureus, Interleukin-18, Nerve Growth Factor and
Semaphorin 3A, an Axon Guidance Molecule, in Pathogenesis and Treatment
of Atopic Dermatitis.
Ikezawa Z, Komori J, Ikezawa Y, Inoue Y, Kirino M, Katsuyama M, Aihara M.
Department of Environmental Immuno-Dermatology, Yokohama City University
Graduate School of Medicine, Yokohama, Japan.
Staphylococcus aureus (SA) is usually present not only in the skin
lesions of atopic dermatitis (AD) but also in the atopic dry skin. SA
discharges various toxins and enzymes that injure the skin, results in
activation of epidermal keratinocytes, which produce and release IL-18.
IL-18 that induces the super Th1 cells secreting IFN-gamma and IL-13 is
supposed to be involved in development of AD and its pathogenesis.
Indeed, the number of SA colonies on the skin surface and the serum
IL-18 levels in patients with AD significantly correlated with the skin
scores of AD lesions. Also, there is strong positive correlation between
the skin scores and serum IL-18 levels in DS-Nh mice (P<0.0001, r=0.64),
which develop considerable AD-like legions when they are housed under
conventional conditions, but develop skin legions with less severity and
less frequency under specific pathogens free (SPF) conditions.
Therefore, they are well-known as model mice of AD, in which SA is
presumed to be critical factor for the development of AD lesions. Also,
theses DS-Nh mice pretreated with Cy developed more remarkable AD-like
lesions in comparison with non-treated ones. The levels of INF-r and
IL-13 in the supernatants of the lymph node cell cultures stimulated
with staphylococcal enterotoxin B (SEB) or ConA were increased in the
Cy-treated mice, although the serum levels of total IgE were not. In
this experiment, we revealed that Cy-treated mice, to which CD25+CD4+
regulatory T cells taken from non-treated ones had been transferred,
developed the AD-like legions with less severity and less number of SA
colonies on the skin surface. Therefore, it is presumed that CD25 +CD4 +
regulatory T cells might be involved in the suppression of super Th1
cells which are induced by IL-18 and are involved in the development of
AD-like lesions rather than IgE production. The efficient induction of
CD25+CD4+ regulatory T cells is expected for the new type of treatment
of AD. We also found that farnesol (F) and xylitol (X) synergistically
inhibited biofilm formation by SA, and indeed the ratio of SA in total
bacteria at sites to which the FX cream containing F and X had been
applied was significantly decreased 1 week later, accompanied with
improvement of AD, when compared with that before application and at
placebo sites. Therefore, the FX cream is a useful skin-care agent for
atopic dry skin colonized by SA. The nerve growth factor (NGF) in the
horny layer (the horn NGF) of skin lesions on the cubital fossa was
collected by tape stripping and measured using ELISA in AD patients
before and after 2 and 4 weeks treatments. Simultaneously, the itch and
eruptions on the whole body and on the lesions, in which the horn NGF
was measured, were recorded, and also the peripheral blood eosinophil
count, serum LDH level and serum total IgE level were examined. The
level of NGF was significantly higher in AD patients than in healthy
controls, correlated with the severity of itch, erythema, scale/xerosis,
the eosinophil count and LDH level, and also significantly decreased
after treatments with olopatadine and/or steroid ointment for 2 and 4
weeks. Therefore, the measurement of the NGF by this harmless method
seems to be useful to assess the severity of AD and the therapeutic
effects on AD. In AD patients, C-fiber in the epidermis increase and
sprout, inducing hypersensitivity, which is considered to aggravate the
disease. Semaphorin 3A (Sema3A), an axon guidance molecule, is a potent
inhibitor of neurite outgrowth of sensory neurons. We administered
recombinant Sema3A intracutaneously into the skin lesions of NC/Nga
mice, an animal model of AD, and investigated the effect of Sema3A on
the skin lesions and their itch. Sema3A dose-dependently improved skin
lesions and attenuated the scratching behavior in NC/Nga mice.
Histological examinations revealed a decrease in the epidermal
thickness, the density of invasive nerve fibers in the epidermis,
inflammatory infiltrate including mast cells and CD4 +T cells, and the
production of IL-4 in the Sema3A-treated lesions. Because the
interruption of the itch-scratch cycle likely contributes to the
improvement of the AD-like lesions, Sema3A is expected to become a
promising treatment of patients with refractory AD.
PMID: 20885908
Am J Rhinol Allergy. 2009 Nov-Dec;23(6):571-4.
Mucosal expression of nerve growth factor and brain-derived neurotrophic
factor in chronic rhinosinusitis.
Coffey CS, Mulligan RM, Schlosser RJ.
The Medical University of South Carolina, Department of
Otolaryngology/Head & Neck Surgery, Charleston, South Carolina 29425,
USA.
BACKGROUND: Allergic rhinitis (AR) is characterized in part by
hyperresponsiveness to nonspecific stimuli, a phenomenon that reflects
the fundamental role of nasal neural pathways in chronic airway
inflammation. Neurotrophins may serve pivotal roles in mediating
hyperresponsiveness in allergic airway disease, although the role of
such neurogenic mediators in chronic rhinosinusitis (CRS) is not well
understood. This study was designed to examine the expression of two
potent neurotrophins, nerve growth factor (NGF) and brain-derived
neurotrophic factor (BDNF), in CRS. METHODS: Inferior turbinate and
sinus mucosa were obtained from CRS patients with and without nasal
polyps (NPs) and from nonallergic controls. Enzyme-linked immunosorbent
assay was used for quantitative determination of tissue concentrations
of NGF and BDNF. RESULTS: Ninety-four tissue samples from 48 patients
were included. Mean concentration of NGF in sinus mucosa was
significantly higher in CRS than controls. CRS without NPs was
associated with a 60% increase in sinus NGF over controls (p < 0.05),
and CRS with NPs was associated with a 140% increase (p < 0.05). Mean
sinus NGF concentration was significantly elevated in allergic subjects
compared with controls (p < 0.01). A similar trend was noted in subjects
with nonallergic CRS, although this did not reach significance. Mean
BDNF concentration was decreased in CRS compared with controls, with the
most significant decrease in patients with polyps (p < 0.05). Mean
turbinate concentration of both NGF and BDNF were similar in controls
and CRS. CONCLUSION: Increased expression of NGF may contribute to
neural hyperresponsiveness in CRS sinus mucosa, particularly those
patients with NP and/or allergies. BDNF expression is decreased in CRS
sinus mucosa. Alterations in neurogenic inflammation may contribute to
the pathophysiology of CRS and provide alternative therapeutic targets.
Publication Types:
* Research Support, Non-U.S. Gov't
PMID: 19958603
39 chronic sinusitis patients had a number of familiar characteristics:
1) three fourths had sinusitis for more than 6 years, 2) about
two-thirds said they had "symptoms all the time", 3) 21/39 patients had
asthma, 4) 23/39 had nasal polyps, 5) 6/39 patients had aspirin
sensitivity; The patients were tested for biofilms, then underwent FESS
surgery. They were assessed before and up to 12 months after surgery
through various scoring systems. The first finding is that 30 out of 39
patients were found to have biofilms, with a majority of patients having
biofilms composed of multiple germs. More than half of those biofilms
included staph, either as the only germ or as one of several. Other
germs found either alone or in combination in the biofilms were
Pseudomonas, Haemophilus influenzae, and fungi. They also cultured
bacteria from intraoperative swabs and found a good number of staph, but
also other species. One interesting finding is that "There was no
correlation between the bacteria isolated via culture and the
species-specific biofilm identified via FISH, in keeping with the
biofilm hypothesis of biofilm bacteria not being culturable via the
conventional techniques." The main finding is that patients with
polymicrobial biofilms, especially with staph, or unimicrobial biofilms
with staph, had worse surgery outcomes than other patients at 12 months.
The authors conclude that a likely explanation for the aggravating role
of staph is that they produce superantigens which in turn elicit an
immune response biaised towards Th2, but that the germs in the biofilm
are protected from this immune response by the biofilm matrix. This
inefficient immune response creates local damage, however, which
severely increases inflammation. <doi: 10.1002/lary.21805>, abstract:
Chronic rhinosinusitis (CRS) patients with biofilms have persistent
postoperative symptoms, ongoing mucosal inflammation, and recurrent
infections. Recent evidence suggests that biofilms of differing species
confer varying disease profiles in CRS patients. We aimed to
prospectively investigate the effects of Staphylococcus aureus,
Pseudomonas aeruginosa, Haemophilus influenzae, and fungal biofilms on
outcomes following endoscopic sinus surgery (ESS). STUDY DESIGN:
Prospective blinded study. METHODS: In this prospective blinded study,
39 patients undergoing ESS for CRS assessed their symptoms
preoperatively using internationally accepted standardized symptom
scoring systems and quality-of-life measures (10-point visual analog
scale, Sino-Nasal Outcome Test-20, global severity of CRS). Their
sinonasal mucosa was graded (Lund-Kennedy scale) and extent of
radiologic disease on computed tomography scans scored (Lund-McKay
scale). Random sinonasal tissue samples were assessed for different
bacterial species forming biofilms by using fluorescent in-situ
hybridization and confocal laser microscopy. For 12 months after
surgery, CRS symptoms, quality of life, and objective evidence of
persisting disease were assessed by using the preoperative tools.
RESULTS: Different bacterial species combinations were found in 30 of 39
patients; 60% of these 30 biofilms were polymicrobial biofilms and 70%
had S aureus biofilms. Preoperative nasendoscopy and radiologic disease
severity were significantly worse in patients with multiple biofilms (P
= .02 and P = .01, respectively), and they had worse postsurgery mucosal
outcomes on endoscopy (P = .01) requiring significantly more
postoperative visits (P = .04). Those with S aureus biofilms progressed
poorly with their symptom scores and quality-of-life outcomes, with
significant differences in nasendoscopy scores (P = .007). CONCLUSIONS:
S. aureus biofilms play a dominant role in negatively affecting outcomes
of ESS with persisting postoperative symptoms, ongoing mucosal
inflammation, and infections [PMID 21647904]
Chronic rhinosinusitis with nasal polyps often represents a chronic
severe inflammatory disease of the upper airways and may serve as a
model for lower airway diseases such as late-onset intrinsic asthma.
Enterotoxins derived from Staphylococcus aureus have been implicated in
the pathophysiology of nasal polyps as disease-modifying factors; recent
findings using therapeutic proof-of-concept approaches support this
hypothesis. RECENT FINDINGS: Nasal polyps (chronic rhinosinusitis with
nasal polyps) are characterized by a T-helper-2 (Th2) dominated cytokine
pattern that includes interleukin-5 and formation of immunoglobulin E
(IgE). This is in contrast to chronic rhinosinusitis without polyps,
which exhibits T-helper-1 biased cytokine release. It is now evident
that the cytokine environment is decisive regarding the impact of S.
aureus derived enterotoxins, which function as superantigens. S. aureus
enterotoxin B further shifts the cytokine pattern in nasal polyps toward
T-helper-2 cytokines (increases greater than twofold for interleukin-2,
interleukin-4 and interleukin-5), but it disfavours the T-regulatory
cytokines interleukin-10 (IL-10) and transforming growth factor-beta1.
Furthermore, S. aureus derived enterotoxins influence local
immunoglobulin synthesis and induce polyclonal immunoglobulin E
production, which may contribute to severe inflammation via activation
of mast cells. SUMMARY: From this new understanding of chronic
rhinosinusitis with nasal polyps, new therapeutic approaches emerge such
as anti-interleukin-5, anti-immunoglobulin E, and antibiotic treatment.
These may enlarge the nonsurgical armentarium [PMID 18188015], ³Role of
staphylococcal superantigens in upper airway disease²
The effect of staphylococcal superantigens (SsAgs) on cutaneous
lymphocyte-associated antigen (CLA)(+) CD4(+) Foxp3(+) T cells of atopic
dermatitis (AD) patients is unknown. OBJECTIVE: To compare the effects
of SsAgs on the ratio, function, and apoptosis of CCR6(+) subtype and
CCR6(-) subtype of CLA(+) CD4(+) Foxp3(+) T cells among AD patients,
asthma/allergic rhinitis (AR) patients without AD, and healthy subjects.
METHODS: Using immunofluorescence staining followed by flow cytometric
analysis, we analysed peripheral blood mononuclear cells cultured with
or without staphylococcal enterotoxin B (SEB) stimulation in 20 AD
patients, 20 asthma/AR patients without AD, and 20 healthy subjects.
RESULTS: SEB decreased CCR6(+) /CCR6(-) ratio in CLA(+) CD4(+) Foxp3(+)
T cells from AD patients and increased CCR6(+) /CCR6(-) ratio in those
from healthy subjects. SEB induced the production of type 2 T helper
cell (Th2) cytokine interleukin (IL)-5 in CCR6(-) subtype and
anti-inflammatory cytokine IL-10 in CCR6(+) subtype of CLA(+) CD4(+)
Foxp3(+) T cells. CLA(+) CD4(+) Foxp3(+) T cells from AD patients
produced more IL-5 and less IL-10 after SEB stimulation than those from
healthy subjects. CCR6(-) subtype of CLA(+) CD4(+) Foxp3(+) T cells from
AD patients and CCR6(+) subtype of those cells from healthy subjects
were more resistant to SEB-induced caspase-3 activation than the other
subtype and those from other subjects. CONCLUSIONS AND CLINICAL
RELEVANCE: Despite a phenotype of regulatory T cells, skin-homing CD4(+)
Foxp3(+) T cells of AD patients exert effector Th2-like function after
SsAgs stimulation, which may aggravate allergic skin inflammation [PMID
21255144]
Toxic shock syndrome (TSS) is an acute, serious systemic illness caused
by bacterial superantigens. Nonavailability of a suitable animal model
until recently has hampered an in-depth understanding of the
pathogenesis of TSS. In the current study, we characterized the early
molecular events underlying TSS using our HLA-DR3 transgenic mouse
model. Gene expression profiling using DNA microarrays identified a
rapid and significant upregulation of several pro- as well as
anti-inflammatory mediators, many of which have never been previously
described in TSS. In vivo administration of staphylococcal enterotoxin B
(SEB) led to an increase in the expression of Th0- (IL-2, 240-fold);
Th1- (IFN-gamma, 360-fold; IL-12, 8-fold); Th2- (IL-4, 53-fold; IL-5,
4-fold) as well as Th17-type cytokines (IL-21, 19-fold; IL-17, 5-fold).
The immunoregulatory cytokines (IL-6, 700-fold; IL-10, 18-fold); CC
chemokines (such as CCL 2, 11, 3, 24, 17, 12, 7), CXC chemokines (such
as CXCL 1, 2, 5, 11, 10, 19); and several proteases (matrix
metalloproteinases 13, 8, 3, and 9) were also upregulated. Serum levels
of several of these cytokines/chemokines were also significantly
elevated. Pathway analyses revealed significant modulation in a variety
of biochemical and cellular functions, providing molecular insights into
the pathogenesis of TSS. Administration of bortezomib, a clinically
approved proteasome inhibitor capable of blocking NF-kappaB pathway, was
able to significantly modulate the expression of a variety of genes
induced by SEB. Thus, our study showed that TSS is a complex process and
emphasized the potential of use of bortezomib in the therapy of
superantigen-induced TSS [PMID 19336531]
It is unresolved whether circulating CD25hiCD4+ T cells in patients with
atopic dermatitis who have elevated IgE (IgE(high)) are regulatory or
effector in nature. OBJECTIVE: To analyze the properties of CD25hi
T-cell subtypes in IgE(high) atopic dermatitis. METHODS: The phenotype
of circulating CD25hi T cells was analyzed by flow cytometry using PBMCs
from patients with atopic dermatitis (total IgE > 250 IU/mL). Cytokines
induced in CD25hi subtypes were analyzed after activation with anti-CD3
mAb (+/-IL-2) and in the presence of activated autologous effector T
cells (CD25negCD4+). Reactivity to bacterial superantigen derived from
the skin-colonizing organism Staphylococcus aureus was also evaluated.
RESULTS: CD25(hi) T cells expressing regulatory T-cell markers (Foxp3,
CCR4, cutaneous lymphocyte-associated antigen) were increased in atopic
dermatitis compared with IgE(low) controls. This phenomenon was linked
to disease severity. Two subtypes of CD25hi T cells were identified on
the basis of differential expression of the chemokine receptor CCR6.
Although the ratio of CCR6+ and CCR6neg subtypes within the CD25hi
subset was unaltered in atopic dermatitis, each subtype proliferated
spontaneously ex vivo, suggesting in vivo activation. Activated CCR6neg
cells secreted T(H)2 cytokines, and coculture with effector T cells
selectively enhanced IL-5 production. Moreover, induction of a
T(H)2-dominated cytokine profile on activation with bacterial
superantigen was restricted to the CCR6neg subtype. CONCLUSION: Despite
a regulatory phenotype, activated CD25hi T cells that lack expression of
CCR6 promote T(H)2 responses [PMID 18177697]
Several factors regulate nerve growth factor (NGF), which is formed from
proNGF by intracellular and extracellular enzymatic cleavage. The close
proximity between mast cells, expressing the protease tryptase, and
NGF-producing smooth-muscle-like peritubular cells in the testis of
infertile patients, led us to examine the question, whether tryptase is
among those factors. Human peritubular cells express functional
tryptase-receptors (PAR-2). Recombinant enzymatically active
beta-tryptase increased NGF levels in the culture medium of primary
human peritubular cells, but the peptide agonist for PAR-2 (SLIGKV) did
not. Neither tryptase, nor the peptide, increased NGF mRNA levels. To
test whether the increase in NGF is due to enzymatic activity of
tryptase, acting on proNGF, supernatants of peritubular cells and
synthetic proNGF were treated with tryptase. Results of Western blot
studies indicate enzymatic cleavage of proNGF by active tryptase.
Heat-inactivated tryptase or SLIGKV were not effective. Mass
spectrometry analysis of in vitro cleavage products from recombinant
tryptase and synthetic proNGF revealed multiple cleavage sites within
the proNGF sequence. The results also indicate the generation of mature
NGF and of smaller NGF fragments, as a result of tryptase action. Thus,
tryptase-secreting mast cells in the vicinity of proNGF/NGF-secreting
cells in any human tissue are likely able to alter the ratios of
proNGF/NGF. As NGF and proNGF have different affinities for their
receptors, this indicates a novel way, how mast cells, via tryptase, can
modify the microenvironment in human tissues with regard to neurotrophin
actions [PMID 21768088], ³Human tryptase cleaves pro-nerve growth factor
(PRONGF): hints of a local, mast cell-dependent regulation of NGF/PRONGF
action²
Cathelicidin dysfunction emerges as a central factor in the pathogenesis
of several cutaneous diseases, including atopic dermatitis, in which
cathelicidin is suppressed; rosacea, in which cathelicidin peptides are
abnormally processed to forms that induce inflammation; and psoriasis,
in which cathelicidin peptide converts self-DNA to a potent stimulus in
an autoinflammatory cascade [PMID 19720207]
involvement of HIF-1alpha & mast cells in keloid formation;; Keloids
represent a prolonged inflammatory fibrotic state with areas that
display distinctive histological features characterized by an abundant
extracellular matrix stroma, a local infiltration of inflammatory cells
including mast cells, and a milieu of enriched cytokines. Previous
studies from our laboratory demonstrated an intrinsic higher level of
HIF-1alpha and VEGF protein expression in keloid tissues compared with
their adjacent unremarkable skins. To further investigate the mechanisms
underlying the elevated expression of HIF-1alpha and VEGF in keloids, we
exposed a co-culture of keloid fibroblasts and mast cells (HMC-1) to
hypoxic conditions and studied the expression of HIF-1alpha and its
target gene, VEGF. Our results showed that hypoxia-dependent HIF-1alpha
protein accumulation and VEGF expression is augmented in keloid
fibroblasts when co-cultured with HMC-1 cells under the condition where
direct cell-cell contact is allowed. But such augmentation is not
observed in the transwell co-culture system whereas fibroblasts and
HMC-1 cells were separated by a porous membrane. Our results also
indicated that the enhancement of hypoxia-mediated activation of ERK1/2
and Akt requires direct cell-cell interaction between mast cells and
keloid fibroblasts, and activation of both ERK1/2 and Akt is involved in
the hypoxia-dependent HIF-1alpha protein accumulation and VEGF
expression in the co-culture system. These findings suggest that under
hypoxic conditions mast cells may contribute, at least in part, to an
elevated expression of HIF-1alpha and VEGF protein in keloids via direct
cell-cell interaction with fibroblasts [PMID 16289155]
Microarray analysis is a popular tool to investigate the function of
genes that are responsible for the phenotype of diseases. Keloid is an
intricate lesion that is probably modulated by interplay of many genes.
We ventured to study the differences of gene expressions between keloids
and normal skin with the aid of a cDNA microarray to explore the
molecular mechanism underlying keloid formation. MATERIALS AND METHODS:
The polymerase chain reaction products of 8400 human genes were spotted
on a chip in array. The DNAs were then fixed on the glass plate by a
series of treatments. Total RNAs were isolated from freshly excised
human keloids and normal skins and then were purified to mRNAs by
Oligotex. Both the mRNAs from keloids and normal skins were reversely
transcribed to cDNAs with the incorporation of fluorescent dUTP for
preparing the hybridization probes. The mixed probes were then
hybridized to the cDNA microarray. After highly stringent washing, the
cDNA microarray was scanned for the fluorescent signals to display the
differences between two kinds of tissues. RESULTS: Among 8400 human
genes, there were 402 genes (4.79%) with different expression levels
between the keloids and normal skins in all cases, 250 genes, including
TGF-beta1 and NGF, were upregulated (2.98%) and 152 downregulated
(1.81%). Analyses of collagen, fibronectin, proteoglycan, growth
factors, and apoptosis-related molecule gene expression confirmed that
our molecular data obtained by cDNA microarray were consistent with the
published biochemical and clinical observations of keloids. Higher
expression of TGF-beta(1) and NGF in keloids versus normal skins was
also testified with reverse transcription polymerase chain reaction
method. CONCLUSIONS: DNA microarray technology is an effective technique
in screening for differences in gene expression between keloid and
normal skin. Many genes are involved in the formation of keloids.
Further analysis of the obtained genes will help to understand the
molecular mechanism of keloid formation [PMID 12957131]