Lopalco L, Pastori C, Cosma A, Burastero S E, Capiluppi B, Boeri E, Beretta A, Lazzarin A, Siccardi A G
DIBIT and Infectious Diseases Clinic, San Raffaele Scientific Institute, Milan, Italy.
AIDS Res Hum Retroviruses. 2000 Jan 20;16(2):109-15. doi: 10.1089/088922200309458.
Despite repeated exposures to HIV-1, some individuals remain seronegative. This study reports that sera from a fraction of exposed seronegative (ESN) subjects showed HIV-neutralizing activity; 5 of 17 ESN sera and none of 17 controls neutralized two different HIV-1 primary isolates (range of neutralizing titers: 1/20 to 1/60). The neutralizing activity was associated with the IgG fraction of 4 of 4 neutralizing ESN sera. Moreover, in 11 of 17 and 9 of 17 ESN sera (but none of the control sera) we found antibodies against HLA class I and CD4, respectively. One of the ESN sera (EU22) neutralized efficiently the primary virus derived from the seropositive partner and showed a good broadly cross-reactive neutralization. Immunoadsorption of two IgG fractions from EU19 and EU22 on peripheral blood mononuclear cells (PBMC) removed virus-neutralizing antibodies. The correlations between the ESN status and neutralizing activity (p<0.05), anti-HLA antibodies (p<0.0002), and anti-CD4 antibodies (p<0.001) were statistically significant. However, there was no statistically significant correlation between neutralizing activity and either anti-HLA or anti-CD4 antibodies. It can therefore be said that exposure to HIV-1 without seroconversion is, in some individuals, associated with HIV-neutralizing antibodies (not directed against viral antigens) and/or with anti-cell autoantibodies, which are possibly specific for cellular antigens involved in the infection/entry process.
尽管多次接触HIV-1，但一些个体仍保持血清学阴性。本研究报告称，一部分暴露后血清学阴性（ESN）受试者的血清显示出HIV中和活性；17份ESN血清中的5份以及17份对照血清中均无中和两种不同HIV-1原始毒株的能力（中和效价范围：1/20至1/60）。中和活性与4份具有中和作用的ESN血清中的IgG组分相关。此外，在17份ESN血清中的11份以及17份ESN血清中的9份（但对照血清中均无）中，我们分别发现了针对HLA I类分子和CD4的抗体。其中一份ESN血清（EU22）能有效中和来自血清学阳性伴侣的原始病毒，并表现出良好的广泛交叉反应中和能力。用EU19和EU22的两个IgG组分对外周血单核细胞（PBMC）进行免疫吸附可去除病毒中和抗体。ESN状态与中和活性（p<0.05）、抗HLA抗体（p<0.0002）和抗CD4抗体（p<0.001）之间的相关性具有统计学意义。然而，中和活性与抗HLA或抗CD4抗体之间均无统计学显著相关性。因此可以说，在一些个体中，未发生血清转化的HIV-1暴露与HIV中和抗体（并非针对病毒抗原）和/或抗细胞自身抗体相关，这些抗体可能针对感染/进入过程中涉及的细胞抗原具有特异性。
