Differential maturation of avidity of IgG antibodies to gp41, p24 and p17 following infection with HIV-1.
We have evaluated solid-phase ELISA IgG antibody avidity studies as a means of identifying cases of recent HIV-1 infection. Although separate studies on the avidity of anti-gp41 and anti-p24 antibodies in seroconvertors have been reported, a comparison of the ability of patients to simultaneously mature their immune response to more than one HIV antigen immediately following seroconversion appears to be lacking. We have demonstrated a maturation in anti-gp41 avidity which reflects the time since seroconversion in all cases. In contrast, however, only some patients produced high-avidity anti-p24 or anti-p17 antibodies during the same time span. While the avidity of anti-gp41 antibodies remained high in cases of non-recent HIV infection, even in the face of advanced disease, we have confirmed the findings of others that the avidity of anti-p24 falls before the onset of ARC or AIDS. Therefore, whilst the avidity of anti-gp41 antibodies could reliably be of value in identifying cases of recent HIV infection, the avidity of anti-p24 or anti-p17 antibodies could not, but may be of prognostic value, even at an early stage. The time taken to reach maximum anti-p17, anti-p24 and anti-gp41 titres was variable, but anti-gp41 titres, like anti-gp41 avidity, remained high. In contrast, anti-p24 titres fell, even during the early followup period in some seroconvertors. Anti-p24 antibody avidity, however, appeared to be a better predictor of disease progression in 'remote' cases than anti-p24 titre. The avidity and titres of these antibodies are presented in relation to the clinical details, p24 antigen status, CD4 and CD8 counts where these are known.
Thomas
H I
HI
Department of Virology, Royal Preston Hospital, UK.
Wilson
S
S
O'Toole
C M
CM
Lister
C M
CM
Saeed
A M
AM
Watkins
R P
RP
Morgan-Capner
P
P
D000328:Adult; D000915:Antibody Affinity; D015683:Gene Products, gag / Q000276:immunology*; D015483:HIV Antibodies / Q000097:blood*; D015488:HIV Antigens / Q000276:immunology*; D016655:HIV Core Protein p24 / Q000276:immunology*; D015700:HIV Envelope Protein gp41 / Q000276:immunology*; D015658:HIV Infections / Q000097:blood / Q000276:immunology*; D006679:HIV Seropositivity / Q000276:immunology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008875:Middle Aged; 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; D015700:HIV Envelope Protein gp41; D007074:Immunoglobulin G; D014764:Viral Proteins; D054301:gag Gene Products, Human Immunodeficiency Virus; C054858:p17 protein, Human Immunodeficiency Virus Type 1