A conserved idiotype and antibodies to retroviral proteins in systemic lupus erythematosus.
22 of 61 systemic lupus erythematosus (SLE) patients produced antibodies to the p24 gag protein of HIV-1 demonstrated by Western blotting. 20 of these 22 patients (91%) also express the 4B4 idiotype (Id 4B4) previously identified on a human anti-Sm monoclonal antibody called 4B4. This represents an enrichment for this Id (seen in only 52% of SLE patients generally). Eight of these 22 SLE patients also have anti-Sm antibody activity. Sm partially inhibits the antibody binding of p24 gag suggesting immunologic cross-reactivity between the retroviral antigen p24 gag and the autoantigen Sm. Anti-Id 4B4 also inhibits p24 gag antibody binding by as much as 40%. Finally the monoclonal antibody 4B4 showed cross-reactivity to Sm and p24 gag. The following points emerge from our studies: (a) SLE patients make antibodies to p24 gag of HIV-1, (b) there is a relationship between immunity to p24 gag and a conserved idiotype, and (c) anti-Sm antibodies can cross-react with p24 gag.
Talal
N
N
Clinical Immunology Section, Audie L. Murphy Memorial Veterans Hospital, San Antonio, Texas 78284.
Garry
R F
RF
Schur
P H
PH
Alexander
S
S
Dauphinée
M J
MJ
Livas
I H
IH
Ballester
A
A
Takei
M
M
Dang
H
H
D001324:Autoantigens / Q000276:immunology; D015153:Blotting, Western; D003429:Cross Reactions; D015683:Gene Products, gag / Q000276:immunology*; D015483:HIV Antibodies / Q000276:immunology*; D015488:HIV Antigens / Q000276:immunology*; D016655:HIV Core Protein p24; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D012191:Retroviridae Proteins / Q000276:immunology*; D017411:Ribonucleoproteins, Small Nuclear; D014758:Viral Core Proteins / Q000276:immunology*; D055517:snRNP Core Proteins
D001324:Autoantigens; D015683:Gene Products, gag; D015483:HIV Antibodies; D015488:HIV Antigens; D016655:HIV Core Protein p24; D007130:Immunoglobulin Idiotypes; D012191:Retroviridae Proteins; D017411:Ribonucleoproteins, Small Nuclear; D014758:Viral Core Proteins; D055517:snRNP Core Proteins