Histiocitose de células de Langerhans: relato de um caso / Langerhans cell histiocytosis: case report

A histiocitose de células de Langerhans corresponde a um grupo heterogêneo de desordens caracterizadas pela proliferação monoclonal de células dendríticas. Predomina na infância e pode afetar qualquer órgão. Relata-se caso de paciente, sexo feminino, 44 anos, apresentando placas espessas, exsudativas, com escamas aderentes aos pelos, localizadas no couro cabeludo, semelhantes a dermatite seborreica, além de fístulas nas axilas, regiões inframamárias e inguinais de evolução há 16 anos. Realizou-se biópsia da lesão cutânea seguida de imunohistoquímica que concluiu diagnóstico de Histiocitose de células de Langerhans. Investigação sistêmica evidenciou acometimento pulmonar concomitante. Até o presente momento existem poucas publicações sobre envolvimento cutâneo em adultos, assim como não há protocolos de tratamento para os mesmos, necessitando maiores estudos para melhor manejo desses pacientes.

Langerhans cell histiocytosis corresponds a heterogeneous group of disorders characterized by monoclonal dendritic cells proliferation, it predominates in childhood which may affect any organ of the body. The case reports of a female patient, aged 44, presenting thick plates with scales adhering to the hairs, scalp located, similar to seborrheic dermatitis, besides fistulas in axillas, inguinal and infra mammary regions. The hypothesis of Langerhans cell histiocytosis was confirmed by cutaneous biopsy and immunohistochemistry. Systemical investigation accused pulmonary involvement. Until now are few publications about adult cutaneous cases, so none treatment protocols are avaible for them. More specific studies are demanded for better management of these patients.

A case of S100-positive atypical juvenile xanthogranuloma: a longitudinal observation and review of the literature / 中华皮肤科杂志

A 3-year-old boy presented with a 3-month history of brown-yellow papules scattered on the trunk.The first skin biopsy showed a dermal infiltrate of many mononuclear histiocytes,eosinophilic granulocytes and a small number of lymphocytes.Immunohistochemical examination of the lesions demonstrated positive reactions with anti-CD68,-S100 and-CD1a (partial) antibodies.After the biopsy,the skin lesions gradually turned dark and partially regressed leaving hyperpigmentation,but new lesions continuously appeared.Four months later,a second biopsy was performed,and showed a dermal infiltrate of histiocytes with eosinophilic granulocytes and a few multinucleated giant cells.Immunohistochemistry showed that the histiocytes stained positive for CD68,but negative for S100 and CD1a.Based on the above findings,the patient was diagnosed with juvenile xanthogranuloma.

The presence of CD8+ invariant NKT cells in mice

Invariant natural killer T (iNKT) cells develop in the thymus upon recognition of CD1d expressed on developing thymocytes. Although CD4 and CD8 coreceptors are not directly involved in the interaction between CD1d and the T cell receptors (TCRs) of iNKT cells, a conspicuous lack of CD8+ iNKT cells in mice raised the question of whether CD8+ iNKT cells are excluded due to negative selection during their thymic development, or if there is no lineage commitment for the development of murine CD8+ iNKT cells. To address this question, we analyzed iNKT cell-specific TCR Valpha14+ transgenic mice, where the Valpha14 transgene forces the generation of iNKT cells. This allows detailed study of the iNKT cell repertoire. We were able to identify CD8+ iNKT cells which respond to the NKT cell-specific glycolipid ligand alpha-galactosylceramide. Unlike conventional iNKT cells, CD8+ iNKT cells produce predominantly IFN-gamma but not IL-4 upon antigen stimulation. We also confirmed the presence of CD8+ iNKT cells in wild type mice. Our results suggest that CD8+ NKT cells do exist in mice, although their population size is quite small. Their Th1-skewed phenotype might explain why the population size of this subtype needs to be controlled tightly.

The effects of melanoma culture supernatants on production of IL-12 and expression of CD14 and CD1a by human monocytes in vitro / 中华皮肤科杂志

85%. The concentrated MCS in different amount was added to the IFN-?(100 pg/mL) and LPS (10 ng/mL) enriched culture media. The IL-12 production by monocytes was determined by the enzyme- linked immunosorbent assay(ELISA).The expression of CD14 and CD1a was analyzed by flow cytometry 5 days after the monocytes were co-cultured with MCS. Results The production of monocytic IL-12 was down-regulated by MCS in a dose dependent manner. The amount of IL-12 from monocytes decreased along with an increased dose (25-100?L) of MCS applied in the reaction. It was also observed that the differentiation from CD14 expressing monocytes to CD1a dendritic cells was impaired by MCS. The ability of MCS to inhibit the production of IL-12 by monocytes and to suppress the differentiation of monocytes to dendritic cells in vitro could be disrupted by PD98059,an ERK specific inhibitor. Conclusions MCS appears to inhibit IL-12p40 production by monocytes and inhibit differentiation of monocytes in vitro via secretion of ERK stimulating factor. The inhibitory factors in MCS and their chemical natures need further research.