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The Acquired Immune Deficiency Syndrome (AIDS) affects the life of millions of people around the world. Although rapid and low cost screening tests are widely available for the diagnosis of HIV infection, the count of CD4+ T lymphocytes remains a drawback in the areas mostly affected by the HIV, being this control imperative for assessing the deterioration of the immunological system and the progression towards AIDS, when the counting of cells falls down 200 cells μL −1 . This paper describes a high-throughput, simple and rapid method for CD4+ T lymphocytes quantification, directly in whole blood, based on a magneto ELISA. The CD4 cells are separated and preconcentrated from whole blood in magnetic particles, and labeled with an enzyme for the optical readout performed with a standard microplate reader. The magneto ELISA is able to reach the whole CD4 counting range of medical interest, being the limit of detection as low as 50 CD4+ cells per μL of whole blood, without any pretreatment. This method is a highly suitable alternative diagnostic tool for the expensive flow cytometry at the community and primary care level, providing a sensitive method but by using instrumentation widely available in low-resource settings laboratories and requiring low-maintenance, as is the case of a microplate reader operated by filters. [ABSTRACT FROM AUTHOR]

Abstract: Prior work demonstrated that immune surveillance of the brain occurs primarily through the blood-cerebrospinal (CSF) fluid barrier rather than the blood-brain barrier endothelium. Recently, we identified epithelial V-like antigen (EVA), an immunoglobulin-like adhesion molecule, as a regulator of blood-CSF barrier integrity in a mouse model. Here we characterized EVA expression and function in human choroid plexus epithelial cells and analyzed its role in CD4 T lymphocyte adhesion. In human choroid plexus epithelial cells and a subset of CD4 T lymphocytes, EVA is expressed at high levels. Epithelial adhesion of T lymphocytes is inhibited by a blocking monoclonal antibody that recognizes EVA. T cell adhesion elicits calcium flux in choroid plexus epithelial cells that also can be blocked by an EVA-specific antibody. EVA-positive cell–cell contacts between epithelial and T cells are associated with increased complexity of cytoskeletal epithelial morphology. These results demonstrate that EVA is expressed in human choroid plexus epithelial cells and CD4 T lymphocytes and regulates CD4+ T lymphocyte adhesion to human choroid plexus epithelial cells in vitro. These data suggest a novel mechanism to regulate CNS immune surveillance. [Copyright &y& Elsevier]

The role of lymphocytes in the experimental progressive glomerulonephritis. Background. Glomerular accmulation of leukocytes, including lymphocytes, is a common feature in most types of glomerulonephritis. However, the role of lymphocytes in progressive glomerulonephritis has not been elucidated. We examined the role of lymphocytes in the development of progressive mesangial proliferative glomerulonephritis induced by two injections of monoclonal antibody 1-22-3 in rats. Methods. To elucidate the role of lymphocytes, circulating lymphocytes were depleted using specific monoclonal antibodies to rat lymphocytes prior to the induction of progressive glomerulonephritis. The effects of lymphocyte depletion on proteinuria and glomerular alterations were assessed 7 and 56 days after the induction of progressive glomerulonephritis. Results. Significant glomerular accmulation of CD4+ T cells, CD8+ T cells, and ED3+-activated macrophage were observed after the induction of glomerulonephritis. Depletion studies showed that continuous treatment with anti-CD5, anti-CD4, or anti-CD8 treatment reduced proteinuria and ameliorated the glomerular lesions on day 56. Depletion of CD4+ T cells also reduced glomerular accmulation of CD8+ T cells and ED3+-activated macrophages, and reduced glomerular expression of mRNA for interferon-gamma (INF-γ) (63.0% in anti-CD5 and 62.3% reduction in anti-CD4). Transit lymphocyte depletion limited in early stage of progressive glomerulonephritis demonstrated that CD4+ T-cell depletion, but not anti-CD8 treatment prevented glomerular injuries 56 days after the induction of progressive glomerulonephritis. Conclusion. CD4+ T cells played a central role in the development of progressive glomerulonephritis, controlling recruitment and activation of CD8+ cytotoxic cells and/or macrophages. [ABSTRACT FROM AUTHOR]