ABSTRACT
In this study we have looked at the effect of lipopolysaccharide (LPS) on the surface antigen expression of cultured monocytes. Monocytes were purified from peripheral blood mononuclear cells (PBMC) and cultured in the presence or absence of LPS. The cultured cells were then stained with anti-MO3, anti-IL-2R and anti-CD4 MoAbs. We have shown that freshly isolated monocytes are IL-2R- and MO3-negative and express CD4 in low density. After overnight culture, without LPS, the expression of these surface markers remained relatively unchanged. However, in the presence of LPS (1 microgram/ml) CD4 expression was reduced to undetectable levels while the expression of IL-2R and MO3 was induced to maximal density. This effect of LPS on monocyte surface antigen expression was demonstrated with LPS preparations from Escherichia coli, Salmonella typhi and Vibrio cholerae. Surface antigen expression after 7 days culture in medium supplemented with non-heat-inactivated serum was essentially as seen after overnight culture, with the exception that LPS-induced IL-2R expression was transient. The ability to prepare monocytes that maintained surface CD4 expression after overnight culture was donor dependent.
Subject(s)
CD4 Antigens/analysis , Escherichia coli , Lipopolysaccharides/pharmacology , Monocytes/immunology , Antigens, Surface/analysis , CD4 Antigens/drug effects , Dose-Response Relationship, Drug , Down-Regulation/drug effects , Humans , Monocytes/cytologyABSTRACT
Five commercial assays for detecting HIV antigen were evaluated using a panel of 40 coded samples in six laboratories. All assays were capable of detecting HIV-1 antigen (HIV-1 Ag), and are likely to prove useful for monitoring supernatant fluids from a variety of cell cultures. The concentration of HIV-1 protein which the assays detected varied from 25 ng/ml down to 25 pg/ml. Three of the five assays were also able to detect HIV-2 Ag. More extensive evaluations are needed to determine the sensitivity and specificity of these assays on serum samples and body fluids.
Subject(s)
Antigens, Viral/analysis , HIV/isolation & purification , Viral Proteins/analysis , Antibodies, Viral/immunology , Cells, Cultured , HIV/immunology , HIV Antibodies , Humans , Immunoenzyme Techniques , Lymphocytes/microbiology , Radioimmunoassay/methodsABSTRACT
The Fairfield Hospital experience with isolation of HIV from peripheral blood leucocytes, cerebrospinal fluid and semen is described. To date HIV has been isolated from single specimens of blood from 45% of patients with AIDS, 35% of patients with lymphadenopathy syndrome AIDS-related complex or ARC and 14% of asymptomatic antibody positive individuals. HIV was recovered from peripheral blood leucocytes in the presence of phytohemagglutinin and interleukin-2. The presence of virus in the supernatant fluid was detected using reverse transcriptase and immunofluorescence assays. Supernatants with borderline activity were confirmed by infection of a continuous cell line.
