CD4+CD28-T cells are expanded in sarcoidosis.

Background And Aim: A subset of CD4+ lymphocytes lacking CD28, an important costimulatory molecule, is increased in certain inflammatory conditions. However, studies have not directly studied CD4+CD28-lymphocytes in patients with chronic sarcoidosis. The aim of this study was to further characterize the CD4+CD28-T cell population in patients with sarcoidosis, particularly those with active disease.

Human immunodeficiency virus gp120 downregulates CD1d cell surface expression.

CD1d is an MHC class I-like surface molecule that presents endogenous glycoplipid antigens. The effect of HIV infection on CD1d surface expression has not yet been reported. FACS analysis revealed significantly lower levels of CD1d on CD14(+) monocytes from HIV-infected subjects compared to HIV-infected subjects on HAART and healthy controls.

Macrophages exposed to lymphotropic and monocytotropic HIV induce similar CTL responses despite differences in productive infection.

Macrophages are accessory cells that are vulnerable to infection by HIV-1. HTLV-IIIB, a lymphotropic strain of HIV, infects macrophages poorly resulting in either no or low levels of virus expression compared to high levels of productive infection after exposure of macrophages to the monocytotropic HIV strain Ada-M. Whether this results in an impaired ability of HTLV-IIIB-exposed macrophages to initiate protective cytotoxic T lymphocyte (CTL) immune responses against these strains is not well defined.