Anti-lymphocyte antibodies in plasma of HIV-1–infected patients preferentially react with MHC class Il-negative T cells and are linked to antibodies against gp41

Abstract

SUMMARYIt has previously beeti shown that HIV-infected patients develop anti-lymphocyte antibodies. The relationship between anti-lymphocyte antibodies and antibodies against different viral antigens is unknown, and it remains controversial whether some lymphocyte subpopulations are targeted preferentially. We have set out using three-colour flow cytometry to measure antibodies against different lymphocyte subsets. Staining with anti-human immunoglobulin and two MoAbs was performed to characterize the immunoglobulin toad of different lymphocyte subsets. Comparison was done between patients' antibody reactivity against HlV-1 antigens and anti-lymphocyte antibodies. We were able to demonstrate the presence of anti-lymphocyte antibodies in approximately 75% of the HIV-infected patients (n = 78) (healthy controls were all negative). MHC class Il-negative T cells showed a stronger reaction wilh anti-lymphocyte antibodies than B eells or MHC class Il-positive T cells. Patients wilh antibodies against CD4 lymphocytes showed a signilicantly higher antibody reaction with the retroviral antigen gp41 than patients without these antibodies. An association between anti-lymphocyte antibodies and antibody reactivity against other HIV-1 antigens was not noticed. In conclusion, anti-lymphocyte antibodies in HIV-Iinfecled patients show a preferential reaetivitiy with T eells which lack expression of MHC class II molecules. There is an increased antibody reactivity against gp41 in patients with anti-CD4* Teell antibodies. The association hints at a specific origin of anti-lymphocyte antibodies in HIV-Iinfected patients due to cross-reactivity with viral epitopes or network phenomena. These anti-CD4 eell antibodies eould be of interest in the elinical course of HIV infection.

Interaction of a Peptide from the Pre-transmembrane Domain of the Severe Acute Respiratory Syndrome Coronavirus Spike Protein with Phospholipid Membranes

“…Porcine lungs were obtained from a local slaughterhouse. Plasma membrane (LE) from lung tissue pneumocytes was obtained according to ref , and lipid extraction was performed according to the Bligh and Dyer procedure using a ratio of 1:1:0.9 (v/v/v) between chloroform, methanol, and the corresponding aqueous sample . All other chemicals were commercial samples of the highest purity available (Sigma-Aldrich, Madrid, Spain).…”