A 7-year analysis of anti-Gag (p17 and p24) antibodies in HIV-1-seropositive patients with haemophilia: immunoglobulin G titre and avidity are early predictors of clinical course.
OBJECTIVE
To study the humoral immune response to HIV-1 p17 and p24 Gag proteins longitudinally and assess any prognostic value.


METHODS
Fifteen HIV-1 infected patients with haemophilia were asymptomatic at entry to the study in 1986. Each patient was monitored at 6- to 12-month intervals for up to 7 years for p17 and p24 immunoglobulin (Ig)G titres, p17 IgG avidity, total IgG, p24 antigenaemia and CD4 cell counts. Results were correlated with the clinical course.


RESULTS
Between 1986 and 1993, six of the patients developed CD4 cell counts below 200 x 10(6)/l (AIDS patients) while nine retained counts above this level (asymptomatic patients). All AIDS patients were characterized by declining IgG titres to p17 and p24 from 1986-1987 onwards. A reduction in specific p17 and p24 IgG preceded, by at least 3-4 years, the onset of CD4 cell depletion (< 200 x 10(6)/l). These six patients also had significantly lower p17 IgG avidity than the asymptomatic patients throughout the study.


CONCLUSIONS
Titres of p17 and p24 IgG appeared to alter in the same manner. A progressive reduction in IgG titres and a low p17 IgG avidity were earlier predictors of disease progression than CD4 cell counts or p24 antigenaemia.
Chargelegue
D
D
Department of Medical Microbiology, London Hospital Medical College, UK.
Colvin
B T
BT
O'Toole
C M
CM
D000328:Adult; D000368:Aged; D000915:Antibody Affinity; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D015683:Gene Products, gag / Q000276:immunology; D015483:HIV Antibodies / Q000097:blood*; D015488:HIV Antigens / Q000276:immunology; D016655:HIV Core Protein p24 / Q000276:immunology; D006679:HIV Seropositivity / Q000097:blood / Q000150:complications* / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006467:Hemophilia A / Q000150:complications*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013997:Time Factors; D014764:Viral Proteins; D054301:gag Gene Products, Human Immunodeficiency Virus
D015683:Gene Products, gag; D015483:HIV Antibodies; D015488:HIV Antigens; D016655:HIV Core Protein p24; D007074:Immunoglobulin G; D014764:Viral Proteins; D054301:gag Gene Products, Human Immunodeficiency Virus; C054858:p17 protein, Human Immunodeficiency Virus Type 1