Journal of Investigative Dermatology Symposium Proceedings最新文献

The Hampton University Skin of Color Research Institute Skin of Color Symposium 2015: From Bench to Bedside was held in Williamsburg, Virginia at the Williamsburg Lodge, November 13–15, 2015. The conference was designed to promote, develop, and advance the education, knowledge, and research of cutaneous disorders disproportionately affecting people of racial and ethnic minority groups. Centered on the theme of “From Bench to Bedside”, the symposium provided a program featuring a diverse panel of nationally recognized physician-scientists, basic scientists, and clinicians who updated attendees on the latest research advances across multiple relevant disciplines, including public health, basic science, and the clinical diagnosis and management of select complex and rare dermatologic conditions. Featured sessions included recent advances in vitiligo, disorders of hyperpigmentation, keloids, central centripetal cicatricial alopecia, and cutaneous lupus.

We expect that the scientific sessions and interactive panel discussions, combined with the synergistic environment that has characterized this conference, will spur the formation of new collaborations and scientific discovery and, ultimately, will culminate in novel treatments for dermatologic disorders disproportionately affecting individuals with skin of color.

Lupus erythematosus is a chronic autoimmune disorder with a protean clinical manifestation affecting virtually every organ including skin, with tremendous variation between patients. This makes it vital to stratify patients on a molecular basis. We used gene microarray technology for large-scale screening combined with bioinformatics to investigate global patterns of gene expression in cutaneous lupus erythematosus to allow further insights into disease heterogeneity. Unbiased clustering exposed a clear separation between cutaneous lupus erythematosus skin and blood samples. Pathway-based analyses of the differentially expressed genes from sample groups within skin and blood showed prominent apoptosis and interferon response signals. Given their well-known role in systemic lupus, the two processes are potentially critical to cutaneous lupus erythematosus as well. We found both coincident and distinct features between systemic lupus and cutaneous lupus erythematosus, as well as several pathways and processes that are specific to the cutaneous disease that offer potential therapeutic choices in the future. Finally, we identified shared cutaneous lupus erythematosus-skin and -blood transcriptional “hot spots” located on the genome that include several differentially expressed genes previously associated with the systemic disease. The differentially expressed genes included in the hot spots with no systemic lupus associations can potentially be targeted in future studies aimed at identifying risk genes related to cutaneous disease.

Vitiligo is a cutaneous autoimmune disease, especially devastating to patients with darker skin tones because of the contrast between unaffected and lesional skin. We studied immune cells infiltrating vitiligo skin and found very few regulatory T cells (Tregs). Vitiligo was not associated with a reduced frequency or function of circulating Tregs. To manipulate Treg function, we used mouse models expressing melanocyte-reactive TCRs, following changes in pelage color. We also isolated splenocytes to measure Treg function and evaluated cutaneous Treg abundance. Even small numbers of Tregs transferred into depigmenting mice could effectively interfere with depigmentation. The same holds true for treatment with rapamycin, readily translatable for use in human patients; such treatment may be well tolerated. Because vitiligo skin is relatively devoid of cells that produce the chemokine CCL22, whereas circulating Tregs express normal levels of its receptor CCR4, we overexpressed Ccl22 in the skin of vitiligo-prone mice to assess the resulting levels of depigmentation. Markedly reduced depigmentation was accompanied by Treg infiltration to the skin. With several options available to support a healthy balance between Tregs and effector T cells, the next challenge will be to render such treatment antigen specific and avoid general immunosuppression.

Keloids are an exuberant response to cutaneous wound healing. Several lines of evidence suggest that keloid scarring is influenced by genetic factors. This review will discuss our current understanding of genetic influences on keloidal scarring via familial inheritance patterns; ethnic differences in prevalence; syndromes with keloid occurrence; linkage analysis, genome-wide association studies, and admixture mapping studies; transforming growth factor beta and p53 variant studies; and human leukocyte antigen polymorphisms.

Central centrifugal cicatricial alopecia (CCCA) is a common and progressive form of lymphocyte predominant scarring alopecia which impacts negatively on the quality of life of those affected. It is seen more commonly in women of African descent with prevalence ranging from 2.7% to 5.7%. Current postulates include genetic inheritance, with traction inducing hairstyling practices and hair chemicals as aggravating factors. Histology reveals a perifollicular lymphocytic inflammation of the lower infundibulum, premature desquamation of the inner root sheath, and fibrous connective tissue. Treatment remains challenging and is directed at suppressing and preventing the inflammation, thus aborting scarring, with surgical intervention reserved for those who have stable disease or absence of histological inflammation. Future research with more patient numbers, focusing on the genetics of CCCA may prove useful in order to fully understand the etiology, thus providing more effective treatments for CCCA.

Antimalarials are used to treat dermatomyositis (DM) and cutaneous lupus erythematosus (CLE). Although hydroxychloroquine (HCQ) is frequently used, addition of quinacrine (QC) has shown additional clinical effects when combined with HCQ. To quantify the effects of HCQ versus QC in suppressing secretion of tumor necrosis factor-α (TNF-α) and IFN-α from the peripheral blood mononuclear cells of DM and CLE patients, lipopolysaccharide-stimulated and control peripheral blood mononuclear cells from DM and CLE patients and control subjects were analyzed for the effect of HCQ and QC on TNF-α and IFN-α production using ELISA testing. Flow cytometry showed the effects of these therapies on intracellular TNF-α in myeloid dendritic cells and monocytes of DM patients and control subjects. QC significantly suppressed TNF-α relative to HCQ from unstimulated and lipopolysaccharide-stimulated peripheral blood mononuclear cells of DM and CLE patients (P < 0.0001). It suppressed IFN-α as significantly as HCQ from cytosine phosphodiester guanine–stimulated peripheral blood mononuclear cells of DM and CLE patients (P < 0.0001). Flow cytometry showed that QC significantly suppressed intracellular expression of TNF-α from the lipopolysaccharide-stimulated myeloid dendritic cells and monocytes of DM patients (P-values ≤ 0.0008). In conclusion, QC likely has a different mechanism of action than HCQ, given the broader inhibition of proinflammatory cytokines, including both TNF-α and IFN-α.