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This section offers news briefs on research papers on dermatology as of June 1, 2015. A study reveals a decrease in regulatory T cells in skin of patients with the autoimmune depigmentation disease vitiligo. A study has identified lupeol via activity-guided purification following screening tests from extracts of medicinal plants, such as Solanum melongena. A research paper reveals the crucial role of ceramides in skin barrier function.

Regulatory T cells are crucial for preventing autoimmunity, but how their function is restrained to allow optimal effector T cells responses in appropriate contexts is unclear. In a recent paper in the Journal of Experimental Medicine, Campbell and colleagues demonstrate that virus-induced type I interferon acts directly on Treg cells to allow for functional antiviral T cell responses. [ABSTRACT FROM AUTHOR]

Immune stimulating activity was compared for lipid vesicles consisting of the total polar lipids of an archaeon Haloferax volcanii, and the eubacteria Planococcus spp. and Bacillus firmus. Each total polar lipid extract readily formed liposomes of similar size, within which the protein antigen ovalbumin was entrapped, with comparable loading and internalization. Subcutaneous immunization of mice resulted in anti-ovalbumin antibody titers for all adjuvants, with memory recall responses that were significantly greater with the archaeal lipid (H. volcanii versus Planococcus). More striking, induction of cytotoxic T cell activity against the entrapped antigen, measured 10 days following a single vaccination (primary response) rapidly declined by week 7 (secondary response after injections on days 0 and 21) in mice immunized with Planococcus spp. liposomes, but was sustained in mice immunized with H. volcanii archaeosomes. Surprisingly, antigen free-Planococcus liposomes evoked potent non-specific inflammatory cytokine production (IL-12 and IL-6) by dendritic cells whereas archaeal H. volcanii vesicles evoked little inflammatory cytokines. This suggested that overt inflammatory response might not necessarily aid sustenance of immunity. B. firmus liposomes consisted of phosphatidylglycerol, phosphatidylethanolamine and cardiolipin and was an ineffective CTL adjuvant, even for initiating a primary response. Considering that the polar lipids of H. volcanii and Planococcus spp. both consist of the same lipid classes (sulfoglycolipids, phosphoglycerols, and cardiolipins), the unique ability of archaeosomes to maintain antigen-specific T cell immunity may be attributable to a property of the archaeal 2,3-diphytanylglycerol lipid core. [Copyright &y& Elsevier]

Human genetic and environmental factors underlie susceptibility to the T cell-mediated autoimmune disease, multiple sclerosis (MS). How the environment influences the pathogenesis of MS has been difficult to parse. A recent paper in Cell shows that environmental antigens that activate myelin-specific T cells can be identified with unprecedented accuracy. [Copyright &y& Elsevier]

Immune suppression by Treg cells must be overcome to mount robust and effective anti-pathogen immune responses. A new paper in Immunity from Medzhitov and colleagues shows that IL-1-dependent activation of MyD88 promotes the development of Th1 cells by rendering them impervious to Treg cell-mediated inhibition. [ABSTRACT FROM AUTHOR]

The author focuses on the technique to generate clinical-grade virus-specific T-cell lines targeting seven viruses described U. Gerdemann and colleagues. The author says that the paper of Gerdemann is a logical extension to the approach involving the adoptive transfer of virus-specific T cells after stem cell transplantation (SCT). He suggests that the development of an effective approach is needed for the new viruses described by the team.

While the human NOTCH1 gene initially was cloned as part of a translocation breakpoint in T cell acute lymphoblastic leukemia (T-ALL) tumors, this translocation is present in only a small percentage of T-ALL patients. A recent paper by demonstrates that novel types of activating mutations in the NOTCH1 gene occur in more than half of all T-ALL cases, implicating NOTCH1 as a major player in the etiology of T-ALL. [Copyright &y& Elsevier]

A recent paper on immunity and tolerance to antigenic determinants on antibody variable-regions (idiotypes) brings back to light the potential of idiotypic interactions among antibodies, B cells and T cells in the regulation of specific immune activities. The functional significance of idiotypic regulation has been established in a variety of systems, both concerning the establishment of ‘pre-immune’ diversity repertoires as well as the clonal regulation of immune responses to foreign and self-antigens. Also, recently the requirement for ‘dominant’ regulatory mechanisms in natural tolerance has received increasing support. It might thus be fruitful to evaluate the possibility that an idiotypic network has a fundamental role in the operation of the regulatory T cells that establish and maintain self-tolerance. [Copyright &y& Elsevier]

This article presents abstracts of papers published in the July 1, 1990 issue of the "Journal of Investigative Dermatology." Cutaneous T-cell Lymphoma is an indolent lymphoma that begins in the skin and may spread to involve other extracutaneous lymphoid sites. The course may be long and protracted, or explosive and rapid. Differences in skin color among different racial groups are determined by multiple factors involved in the production, packaging, and distribution of melanin in the skin. Melanin is a complex heteropolymer that provides protection for the epidermis by absorbing ultraviolet and visible light across a broad spectrum.

This article presents information about current research in the field of dermatology. According to a research paper published in a 2004 issue of the "British Journal of Dermatology," envelope proteins of the human endogenous retroviruses family are expressed in human normal, psoriatic and atopic skin by immunostaining and western blotting and that their expressions are regulated by ultra violet irradiation. Another study published in a 2004 issue of the "British Journal of Dermatology," looked at which T cell attracting chemokines are involved in allergic contact dermatitis models in mice which differ in their cytokine expression profiles.