Characterization of autoantibodies to natural killer cells in HIV-infected patients.
Natural killer (NK) cells in HIV-infected patients have a reduced ability to generate non-MHC restricted cytotoxicity to a variety of target cells. The authors investigated antibodies to NK cells in HIV-infected patients and evaluated effects of these antibodies to NK cell numbers and function. Antibodies to NK cells were determined in 160 HIV-infected patients and 35 healthy controls. Flow cytometric whole blood methods were developed to detect antibodies to NK cells. Antibodies to asialo-GM1 were detected by TLC immunostaining. The presence of antibodies to NK cells was demonstrated in plasma of about one-third (54/160) of HIV-infected patients but rarely in controls (2/35). Auto-antibodies bound to NK cells in vivo and were detected by a strong increase of surface immunoglobulin (Ig) on NK cells of HIV-infected patients. Anti-NK cell antibodies were warmreactive antibodies rather of IgG than of IgM phenotype. The prevalence of specific antibodies to asialo-GM1 was low (12.5%). Numbers of circulating NK cells did not differ significantly between antibody positive (99.5/microliters) and antibody negative (141/microliters) patients (P = 0.3). However, pre-incubation of healthy donors' NK cells with autoantibody positive plasma significantly inhibited cytotoxicity to K562 leukaemic cells (P = 0.002). Autoantibodies to NK cells in HIV-infected patients are present in the plasma of one-third of HIV-infected patients and are bound to NK cells in vivo. There is evidence that these autoantibodies can induce NK cell defects similar to those seen in vivo.
Müller
C
C
University of Bonn, Department of Dermatology, Germany.
Szangolies
M
M
Kukel
S
S
Kiehl
M
M
Sorice
M
M
Griggi
T
T
Lenti
L
L
Bauer
R
R
D000888:Antibodies, Anti-Idiotypic / Q000097:blood; D000920:Antibody-Dependent Cell Cytotoxicity; D001323:Autoantibodies / Q000097:blood*; D001772:Blood Cell Count; D005677:G(M1) Ganglioside / Q000276:immunology; D015658:HIV Infections / Q000097:blood* / Q000276:immunology*; D006801:Humans; D007694:Killer Cells, Natural / Q000737:chemistry / Q000276:immunology*; D011947:Receptors, Antigen, B-Cell / Q000378:metabolism; D017452:Receptors, IgG / Q000096:biosynthesis
D000888:Antibodies, Anti-Idiotypic; D001323:Autoantibodies; D011947:Receptors, Antigen, B-Cell; D017452:Receptors, IgG; D005677:G(M1) Ganglioside; C018835:asialo GM1 ganglioside