032 Staphylococcus aureus enterotoxins modulate IL-22-secreting cells in adults with atopic dermatitis

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031
IgG from atopic dermatitis patients induces IL-17 and IL-10 production in
infant intra-thymic TCD4 and TCD8 cells
FR Sgnotto
1
, MG Oliveira
1
, AAL Lira
1
, AHS Inoue
1
, TO Titz
1
, RL Orfali
2
, L Bento-de-Souza
3
,
MN Sato
1
, V Aoki
2
, AJS Duarte
4
and JR Victor
1
1 Department of Dermatology, University of
Sao Paulo Medical School, Sao Paulo, Brazil, 2 Department of Dermatology, University of
Sao Paulo School of Medicine, Sao Paulo, Brazil, 3 Division of Pathology, University of Sao
Paulo School of Medicine, Sao Paulo, Brazil and 4 Division of Pathology, University of Sao
Paulo Medical School, Sao Paulo, Brazil
IgG modulates
ab
T cell cytokine production during the maturation process in human thymus.
We aimed to investigate whether IgG from atopic dermatitis (AD) patients can modulate in
vitro cytokine production of infant intra-thymic TCD4 and TCD8 cells. Thymic tissue was
obtained from newborn children from non-atopic mothers, and thymocytes were cultured for
6 days with purified IgG from AD patients, with IVIg or mock conditions as controls. Cells
were gated as double positive T cells (TDP- CD4+CD8+), TCD4 cells or TCD8 cells, and
levels of IL-17, IFN-
g
, TNF-
a
, IL-4, IL-10 and TGF-
b
were evaluated by flow cytometry. IgG of
AD individuals induced enhanced IL-17 (p 0.05) and IL-10 (p 0.05) production by intra-
thymic TDP, TCD4 and TCD8 cells of infants, and of TGF-
b
(p 0.05), in TDP and TCD8
cells. Moreover, IgG from AD patients reduced IFN-
g
production (p 0.05) in TCD4 cells.
IgG of AD patients can stimulate cytokine production in infant thymocytes and resembles the
peripheral profile observed in adults. These findings suggest a novel mechanism that can
contribute to AD pathogenesis.
032
Staphylococcus aureus enterotoxins modulate IL-22-secreting cells in adults
with atopic dermatitis
RL Orfali
1
, LMS Oliveira
1
, JF Lima
1
, GC Carvalho
1
, YAL Ramos
1
, NZ Pereira
1
, NP Vieira
1
,MC
Zaniboni
1
, MN Sato
2
and V Aoki
1
1 Department of Dermatology, University of Sao Paulo
School of Medicine, Sao Paulo, Brazil and 2 Department of Dermatology, University of Sao
Paulo Medical School, Sao Paulo, Brazil
Atopic dermatitis (AD) is a chronic inflammatory skin disease with skin colonization by
Staphylococcus aureus. Interleukin (IL)-22 triggers antimicrobial peptide (AMP) elaboration
and enhances immunune responses. In AD, IL-22 is related to epidermal hyperplasia, kera-
tinocyte apoptosis, and inhibition of AMP production. We aimed to evaluate the impact of
staphylococcal enterotoxins (SEA and SEB) on the Tc22/Th22 induction in the peripheral
blood of AD patients and on CD4
+
/CD8
+
T cells expressing IL-22 in AD skin. Our study
showed inhibition of SEA and SEB response by Th22 cells (p 0.05) in AD patients, and an
enhanced response to the bacterial stimuli by Tc22 cells (p 0.05). In AD skin, we detected
increased IL-22 transcript expression and T lymphocytes expressing IL-22 (p 0.01).
Together, our results provide two major findings in response to staphylococcal enterotoxins in
adults with AD: dysfunctional CD4
+
IL-22 secreting T cells and increased Tc22 cells. Our
hypothesis reinforces the relevance of CD8 T cells modulated by staphylococcal enterotoxins
as a potential source of IL-22 in adults with AD, which is relevant for the maintenance of
immunological imbalance.
033
Increased expression of IL-31, IL-31RA and OSMR
b
in bullous pemphigoid
I Bac
1
, ON Horva
´th
1
, M Flaig
2
, T Vancsik
3
, S Vural
2
, T Ruzicka
4
and M Sa
´rdy
5
1 Ludwig-
Maximilian University, Department of Dermatology and Allergology, Munich, Germany, 2
Ludwig Maximilian University, Department of Dermatology and Allergology, Munich, Ger-
many, 3 Semmelweis University, Department of Pathology, Budapest, Hungary, 4
Department of Dermatology and Allergology, Ludwig Maximilian University Munich,
Munich, Germany and 5 Semmelweis University, Department of Dermatology, Venereology
and Dermatooncology, Budapest, Hungary
Bullous pemphigoid (BP) is characterized by intense pruritus. Serum levels and tissue
expression of Interleukin-31 (IL-31) have been found to be increased in pruritic skin disorders
such as atopic eczema (AE) and prurigo nodularis (PN). We aimed to investigate the
expression of IL-31 and its receptors [IL-31 receptor alpha (IL-31RA) and oncostatin M re-
ceptor beta (OSMR
b
)] in the skin of classical and atypical forms of BP patients. Immuno-
histochemical staining was performed in biopsy specimens of 16 BP patients (8 classical BP, 5
eczema-like BP, 3 pemphigoid nodularis) and compared with 4 AE, 2 PN and 5 normal skin
samples. The stained slides were scanned and computer-assisted analysis of expression was
performed on the digital slides. Cutaneous expression of IL-31 was increased in BP and AE but
not in PN patients as compared to normal skin (p<0,05) with AE sections showing the highest
IL-31 expression. IL-31RA and OSMR
b
expression was increased in BP but not in AE and PN
(p<0,05). Skin samples of BP patients expressed mostly IL-31RA independent of clinical form.
Epidermal expression of IL-31 and its receptors was significantly higher than dermal
expression in BP sections (p<0,05).In conclusion, IL-31, IL-31RA and OSMR
b
expression was
increased in BP sections with IL-31RA showing the highest expression. Keratinocytes showed
predominant immunoreactivity of IL-31and its receptors. Thus, epidermal expression of IL-31
and its receptors may be related to pruritus in BP.
034
Langerhans cells from aged mice display changes in gene expression and
antigen presentation to responsive T cells
J Lam
1
, W Ding
1
,ZTuo
2
, E Chuang
1
, J Wagner
3
and RD Granstein
1
1 Dermatology, Weill
Cornell Medicine, New York, NY, 2 Microbiology and Immunology, Weill Cornell Medi-
cine, New York, NY and 3 Weill Cornell Medicine, New York, NY
Langerhans cells (LC) are antigen presenting cells of the epidermis that initiate antigen-spe-
cific immune responses under some circumstances while, in the steady state, they may also
serve to down-regulate immune responses. Important LC functions decline with age; LCs from
aged mice have impaired migratory behavior and impaired ability to promote CD4
+
and
CD8
+
T cell (TC) proliferation. We have found that LCs from older mice (>12 months) are less
efficient at eliciting IL-6, IL-17A and IL-22 responses from antigen-specific CD4
+
TCs
compared to LCs from younger mice (323-339) to responsive TCs (from DO11.10 mice) and
validated by qPCR after in vitro co-culture of LCs and TCs with 1
m
M cOVA. To explore the
mechanisms of these age-related functional changes in antigen presentation, we performed
RNA transcriptome analyses of LCs from young (n¼5) and old LCs (n¼5) using Next Gen-
eration Sequencing (HiSeq4000). STAR was used to align raw sequencing reads to the mouse
GRCm38 reference genome. Raw read counts were calculated using HTseq-count. Differ-
ential expression analysis was performed using the DEseq2 package. We identified 42 genes
that were up-regulated by more than 2-fold and selected 5 genes that were significantly up-
regulated in LCs from old mice (PREX2, CDH17, CD209D, CASP12, CADPS2) (padj <1x10
-
20
) and three genes (CXCL2, MEF2C, RGS7BP) that were significantly down-regulated in older
mice (padj <1x10
-20
). We validated these changes using qPCR. These genes are involved in
metabolic signaling, cell proliferation, cell migration, cell adhesion, antigen processing,
protein degradation, and apoptosis. We hypothesize that some of these changes in gene
expression may contribute to age-associated decline in immune function including the
robustness of LC antigen presentation for IL-6, IL-17A, and IL-22 responses.
035
Sensory nerves promote cutaneous immune reaction by promoting dendritic
cell functions
A Otsuka
1
, C Nakashima
1
and K Kabashima
2
1 Department of Dermatology, Kyoto Uni-
versity, Kyoto, Japan and 2 Department of Dermatology, Kyoto University, Kyoto City, Japan
Although the main function of sensory nerves in cutaneous allergic diseases is considered to
be induction of pruritus, they are also known to directly influence local immune responses.
However, the underlying mechanisms for how sensory nerves influence cutaneous acquired
immune responses are still unknown. We observed that the contact hypersensitivity (CHS)
response was attenuated in mice after sensory nerve denervation. This effect was observed by
denervation during the sensitization phase of CHS. Comprehensive mRNA expression anal-
ysis of dorsal root ganglia (DRG) and keratinocytes revealed that the neuropeptide pituitary
adenylate cyclase activating polypeptide (PACAP) was increased after hapten application.
Interestingly, the PACAPadministration restored the attenuated CHS response by denervation.
We next evaluated the effect of PACAP on dendritic cells (DCs) and found that DC migration,
which is known to be essential for the development of CHS, was reduced in both denervated
mice and mice treated with a PACAP inhibitor. Direct in vitro exposure of DCs to PACAP
resulted in increased expression of CCR7 and CXCR4, which are chemokine receptors
essential for cutaneous DC migration. Taken together, the present study suggests an emerging
new paradigm whereby nociceptive fibers integrate environmental signals to modulate a
variety of cutaneous immune responses through PACAP.
036
Keratinocyte-derived IL-15 links oxidative stress to melanocytes immunologic
destruction in vitiligo
X Chen
1
, J Chen
1
, P Kang
1
,SLi
1
, G Wang
1
, T Gao
1
and C Li
1
1 Department of Dermatology,
Xijing Hospital, Fourth Military Medical University, Xi’an, Shaanxi, China
Oxidative stress is critical for T cell-mediated killing of melanocytes in vitiligo. IL15, a
pleiotropic cytokine, acts on virtually each cell type of the innate and adaptive immune
system. However, whether IL-15 plays an immune-related pathologic role in vitiligo and its
linkage to oxidative stress has not been investigated. In our study, we found that IL-15 was
prominently expressed in keratinocytes(KCs) in the epidermis and its expression was mark-
edly up-regulated in vitiligo lesions compared with healthy controls. Notably, IL-15 expres-
sion was highly correlated with the H
2
O
2
contents in vitiligo lesions. In vitro studies showed
that H
2
O
2
treatment was able to increase IL-15 expression in KCs by activating NF-
k
B
pathway, and IL-15 receptor
a
(IL-15R
a
) could concurrently chaperone IL-15 to KCs mem-
brane. We then employed KC-CD8
+
T cell coculture system and proved that IL-15 trans-
presentation in KCs induced by H
2
O
2
significantly promoted CD8
+
T cell activation, cyto-
toxicity, proliferation and differentiation, leading to the increased ratio of
CD49a
+
CD69
+
CD8
+
T cells. Furthermore, neither the knockdown of IL-15R
a
or blockade of
cell-to-cell contact ameliorated the function of CD8
+
T. Taken together, our results demon-
strate that oxidative stress could activate CD8
+
T cell-mediated autoimmune destruction of
melanocytes by enhancing IL-15 expression and its membrane trans-presentation in KCs. KC-
derived IL-15 may be a potential novel therapeutic target for vitiligo treatment.
ABSTRACTS | Adaptive and Auto-Immunity
S6 Journal of Investigative Dermatology (2018), Volume 138