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Objective: Behcet's disease (BD) is a multisystemic disease, with vasculitic lesions in the oral and genital mucosa, eyes, joints, skin and brain. We have previously found that γ δ T cells are increased in peripheral blood of BD patients. The aim of this study was to investigate the extent of γ δ T cells in oral biopsies from BD patients with special emphasis on the restriction of V γ and V δ usage. Patients and methods: Expression of V γ and V δ chains on peripheral blood γ δ T cells from 31 BD patients and 19 healthy controls was analysed by flow cytometry and the expression of V γ and V δ chains in nine ulcerated and eight non-ulcerated oral mucosa from BD patients and non-ulcerated oral mucosa from three healthy controls was analysed by immunohistochemistry. Results: V γ9 and V δ2 were the predominant chains expressed in peripheral blood of BD patients, although other V γ and V δ chains were also expressed. The presence of γ δ T cells was only observed in the ulcerated oral mucosa but not in the non-ulcerated mucosa from the BD patients, and not in the non-ulcerated mucosa from the healthy controls. These γ δ T cells showed no preferential expression of any of the V γ or V δ chains. Conclusion: These data suggest a polyclonal rather than oligoclonal activation of the γ δ T cells. This may indicate that during repeated inflammation of the oral mucosa, the γ δ T cells are responding to a wide variety of antigenic stimuli with consequent expansion of γ δ T cells expressing various V γ and V δ chains and that different antigenic stimuli or responses may be responsible for the clinical heterogeneity of the disease. [ABSTRACT FROM AUTHOR]

Rectal and cervicovaginal mucosa are common routes of transmission of HIV, although the mechanism of transmission is unknown. We have investigated human rectal and cervicovaginal epithelia for the expression of complement receptors (CR) and cell adhesion molecules which may be involved in HIV and other infections. In rectal mucosa, CR3 was detected in the surface and crypt epithelial cells by immunohistology, using MoAbs to CD18 and CD11b in 10 out of 15 specimens. RNA transcripts encoding both CD11b and CD18 were also demonstrated in surface and crypt epithelial cells by in situ hybridization. Although CD11b was detected in the epithelial cells in three out of the 14 cervicovaginal specimens, we were unable to detect CD18. We suggest that expression of the CD11b/CD18 heterodimer might facilitate transmission of HIV by enhancing binding of HIV-antibody complexes in seminal fluid to epithelial cells. Alternatively, since intercellular adhesion molecule-1 (ICAM-1) is a receptor for CD11b/CD18, this may promote adhesion between epithelial cells and HIV-infected mononuclear cells in seminal fluid. [ABSTRACT FROM AUTHOR]