Frequent detection of HIV- and IgG-specific IgM and IgA antibodies in HIV-positive cord-blood sera: fine analysis by western blot.
Cord-blood sera of 36 babies born to HIV-positive mothers in Switzerland were tested for immunoglobulin (Ig) M or IgA by HIV Western blot. IgM was found in 28, and IgA in 19 of unabsorbed sera. Preabsorption with immobilized protein A or G was used to remove IgG, which allowed differentiation between HIV-specific and IgG-specific IgM or IgA. Protein G proved superior and showed that 30% of 23 sera had HIV-specific IgM, while 48% had HIV-specific IgA. HIV-specific IgM and/or IgA was found in 13 out of 21 cases (62%); four out of 21 (19%) had both. HIV-specific IgM reacted most frequently with pol or env proteins, while HIV-specific IgA reacted more frequently with gag than pol; no IgA were directed against env proteins. IgG-specific IgM and IgA, mostly at gag bands, were present in 83 and 38%, respectively. Thus, a large percentage of children born to HIV-positive mothers have HIV-specific IgA and/or IgM which can be distinguished from IgG-specific IgA or IgM, which is also present in the majority of such children. Future studies will have to show whether these antibodies are of diagnostic relevance.
Schüpbach
J
J
Swiss National Center for Retroviruses, University of Zurich.
Wunderli
W
W
Kind
C
C
Kernen
R
R
Baumgartner
A
A
Tomasik
Z
Z
D015492:AIDS Serodiagnosis / Q000379:methods*; D015153:Blotting, Western / Q000379:methods; D005260:Female; D005312:Fetal Blood / Q000276:immunology*; D015686:Gene Products, env / Q000276:immunology; D015683:Gene Products, gag / Q000276:immunology; D015684:Gene Products, pol / Q000276:immunology; D015483:HIV Antibodies / Q000032:analysis / Q000276:immunology*; D015488:HIV Antigens / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology*; D006679:HIV Seropositivity / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis* / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis / Q000276:immunology; D007075:Immunoglobulin M / Q000032:analysis* / Q000276:immunology; D007231:Infant, Newborn; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology*; D013557:Switzerland
D015686:Gene Products, env; D015683:Gene Products, gag; D015684:Gene Products, pol; D015483:HIV Antibodies; D015488:HIV Antigens; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M