home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
The Arsenal Files 6
/
The Arsenal Files 6 (Arsenal Computer).ISO
/
health
/
med9605a.zip
/
M9650224.TXT
< prev
next >
Wrap
Text File
|
1996-03-09
|
3KB
|
53 lines
Document 0224
DOCN M9650224
TI Cross-reactive antibodies between HIV-gp120 and platelet gpIIIa (CD61)
in HIV-related immune thrombocytopenic purpura.
DT 9605
AU Bettaieb A; Oksenhendler E; Duedari N; Bierling P; Laboratoire
d'Immunologie Leuco-Plaquettaire, Centre de; Transfusion, Creteil,
France.
SO Clin Exp Immunol. 1996 Jan;103(1):19-23. Unique Identifier : AIDSLINE
MED/96150276
AB We have previously demonstrated that immune platelet destruction
observed in an AIDS-free HIV-infected patient was associated with the
presence of a cross-reactive antibody recognizing both HIV-glycoprotein
(gp)120 and platelet gpIIIa (CD61). We have now investigated the
presence of such antibodies in other HIV-infected patients, together
with the molecular structure of the cross-reactive epitope. Platelet
gpIIb/IIIa antibodies were characterized in sera from HIV-infected
patients with immune thrombocytopenic purpura by means of an ELISA and a
radio-immunoprecipitation procedure (RIP). The platelet antibodies were
purified and tested for their ability to recognize HIV-gp. We also tried
to characterize the antibody target epitope on HIV-gp120 using
recombinant gp and synthetic peptides. IgG with anti-gpIIb/IIIa activity
were detected, by means of an ELISA with purified gpIIb/IIIa, in 101/138
(73%) sera from HIV-infected patients with immune thrombocytopenic
purpura. The platelet antibodies were purified from 23 sera by
absorption/elution on purified immobilized platelet gpIIb/IIIa, and
recognition of gpIIIa was confirmed in eight cases with a RIP.
Furthermore, the presence of a cross-reactive antibody between HIV-gp120
and platelet gpIIIa was demonstrated in 18/18 patients (including the
eight with a confirmed gpIIIa antibody) by the ability of the serum
HIV-gp160/120 antibodies to bind to purified gpIIb/IIIa. The
cross-reactive epitope was shown to be independent of the carbohydrate
moieties of gp120, since deglycosylation of two recombinant (r)-gp120s
did not abolish antibody binding. However, the antibody did not
recognize synthetic gp120 peptides spanning 355 of the 516 amino acids
of gp120, particularly the four regions exhibiting sequences of four or
five consecutive amino acids that are identical between r-gp120 and
gpIIIa. Our results thus support the hypothesis that the cross-reactive
antibody recognizes the conformational structure of gp120. These results
strongly suggest that molecular mimicry between HIV-gp120 and platelet
gpIIIa may be important in the pathogenesis of immune thrombocytopenia
in AIDS-free HIV-infected patients.
DE Antigens, CD/*IMMUNOLOGY Autoantibodies/*BLOOD
Carbohydrates/IMMUNOLOGY Cross Reactions Epitopes/IMMUNOLOGY Human
HIV Envelope Protein gp120/*IMMUNOLOGY HIV Infections/BLOOD/*IMMUNOLOGY
HIV-1/*IMMUNOLOGY Platelet Glycoprotein GPIIb-IIIa Complex/*IMMUNOLOGY
Platelet Membrane Glycoproteins/*IMMUNOLOGY Purpura, Thrombocytopenic,
Idiopathic/BLOOD/*IMMUNOLOGY Support, Non-U.S. Gov't JOURNAL ARTICLE
SOURCE: National Library of Medicine. NOTICE: This material may be
protected by Copyright Law (Title 17, U.S.Code).