Langerhans' cell histiocytosis (LCH) is one of the 'histiocytosis disorders', as defined by the Histiocyte Society. LCH is an abnormal proliferation and dissemination of clonal Langerhans' cells in which they accumulate, along with other inflammatory cells, and form tissue granulomas in different organs. It is named after the appearance of the cells, which resemble the normal dendritic cells fo...

Protozoan parasites of the genus Leishmania exist as obligatory intracellular amastigotes and invade macrophages and Langerhans cells, the dendritic cells of the skin. Langerhans cells are much more efficient in presenting Leishmania major antigen to T cells than macrophages are and have the unique ability to retain parasite antigen in immunogenic form for prolonged periods. To analyze the mech...

We have investigated normal human corneas for the presence of T6-marker on Langerhans cells. With the exception of one pair of newborn corneas and two pairs of very young infant corneas, all HLA-DR-positive cells in central and peripheral corneal epithelium were T6-negative by double-labeled immunofluorescence. In contrast, epidermal sheets from normal human eyelid skin displayed positive stain...

Heterosexual transmission of HIV is the most common mode of infection in the global HIV epidemic. In the absence of an effective vaccine, there is an urgent need for additional strategies to prevent new HIV infections. Evidence from a variety of investigations, including epidemiologic studies on sexual transmission, in vivo studies in rhesus monkey, and ex vivo studies using human explant model...

Histiocytosis X, or Langerhans cell histiocytosis (LCH), is a rare disease, with an estimated incidence of 1/200,000 per year in children under 15 years of age. It has a wide clinical spectrum, from single bone involvement (eosinophilic granuloma) to multisystemic disease with organ failure. The treatment of LCH is still controversial. While single system disease may spontaneously recover or re...

Pulmonary Langerhans' cell histiocytosis (PLCH) remains an important diagnostic consideration in the differential diagnosis of diffuse infiltrative lung disease, particular among smokers. This review highlights recent progress in our understanding of the etiology, clinical presentation, and diagnostic and therapeutic approaches to this unusual lung disorder. Evolving studies strongly link the b...

Pulmonary Langerhans cell Histiocytosis is a rare granulomatous disease affecting both sexes, with greater incidence in the second and third decades of life; smoking appears to be the most important risk factor. Its etiology is unknown, although there are data indicating an uncontrolled immune response as possible cause, sustained by the Langerhans cells, antigen presenting cells for T lymphocy...

A 5 year old boy presented with papules and nodules on face, chest and upper extremities and seborrhea of scalp for 4 years. Some old healed scars were also present. Lesions were pruritic to begin with but were non-itchy. Examination revealed erythematous plaques and nodules on face and upper limbs. Lesions were more marked on forehead, cheek (Fig. 1) and dorsum of hands. There were contracture...

It has recently been shown that hapten-modified cultured Langerhans cells are able to activate small resting syngeneic L3T4+ T helper cells from nonsensitized animals. Repeated stimulation of these T cells with hapten-modified cultured Langerhans cells leads to the establishment of L3T4+ hapten-specific interleukin-4-producing T-cell lines. Here we report on further characteristics of primary h...

Our study aims at characterizing 3D nuclear architecture of distinct sub-populations epidermal cells. We have performed FISH & RASER-FISH, combined with immunofluorescence and analysis widefield SIM super-resolution on cryosections cultured Organization the nucleus significantly differs between cell types during differentiation. Previous studies showed that heratinocyte(KC) differentiation is a...