Natural killer activity from normal peripheral blood lymphocytes against a human T lymphotropic retrovirus type III (HTLV-III)-infected cell line.
An H9-HTLV-III-infected cell line was used as a target in a short-term (3-hr) Cr release assay to assess its sensitivity to lysis by peripheral blood lymphocytes (PBL) from normal donors. The single cell cytotoxicity assay (SCCA) on poly-L-lysine-coated coverslips was used to investigate further the mechanism of binding and killing. Uninfected H9 and K562 cell lines were studied as controls. Our results argue in favour of a natural killer (NK) mechanism being operative on an H9-HTLV-III-infected cell line owing to the following findings: (1) the cell line is sensitive to lysis in a short-term assay; (2) its sensitivity is significantly higher than K562; and (3) the kinetics of lysis, as assessed by SCCA, is similar to that of K562, with a more efficient killing being detectable against H9-HTLV-III. Furthermore, a phenotypic analysis of effector cells suggests that CD4+ lymphocytes are also involved in the lysis of this target. Our data provide evidence for an immune mechanism that may be operative in HTLV-III infection. We then studied, by this method, five groups of patients: one (n = 20) affected by acquired immunodeficiency syndrome (AIDS), one (n = 20) by AIDS-related complex (ARC), one (n = 20) by lymphadenopathy syndrome (LAS), one group (n = 40) of HTLV-III seropositive, apparently healthy people, and one (n = 40) of healthy HTLV-III seronegatives.(ABSTRACT TRUNCATED AT 250 WORDS)
Sirianni
M C
MC
Department of Allergy and Clinical Immunology, University of Rome, La Sapienza, Italy.
De Sanctis
G
G
Macchi
B
B
Soddu
S
S
Ensoli
F
F
Aiuti
F
F
Fontana
L
L
D000386:AIDS-Related Complex / Q000276:immunology; D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D002460:Cell Line; D003601:Cytotoxicity Tests, Immunologic; D006679:HIV Seropositivity / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D008214:Lymphocytes / Q000145:classification