Long-Term Evaluation of HIV Antigen and Antibodies to p24 and gp41 in Patients with Hemophilia

Abstract

To investigate the relation between human immunodeficiency virus (HIV) antigenemia and clinical manifestations of HIV infections, we studied 96 patients with hemophilia who were positive for HIV antibody, for a median of 34 months. Every 4 to 10 months a clinical and laboratory examination was performed and serum samples were tested for three HIV markers: HIV antigen, antibody to p24, and antibody to gp41. Twenty-two subjects (23 percent) were found to be positive for HIV antigen: 8 were positive upon entry and remained so (Group 1), and 14 became positive during the study, 4 to 26 months after HIV antibody appeared (seroconversion), 13 of whom remained positive for HIV antigen (Group 2). Most subjects positive for HIV antigen had low or undetectable titers of antibody to p24, whereas the antibody titer to gp41 remained high. In Group 2, patients with low p24 antibody titers had further decreases in their titers before or at the time HIV antigen appeared. Once present, HIV antigen persisted and tended to increase in concentration. In contrast to Group 3 (negative for HIV antigen, low anti-p24 titer) and 4 (negative for HIV antigen, high anti-p24 titer), the groups positive for HIV antigen had significantly higher incidences of acquired immunodeficiency syndrome (P = 0.05), immunodeficiency-related infections (P less than 0.001), and immune thrombocytopenia (P = 0.001), and had more severe disease as measured by the Walter Reed staging system (P less than 0.001). In this study, HIV antigen appeared to be a better predictive marker of HIV-related complications than the absolute T4+ count. These results suggest that HIV antigenemia indicates a poor clinical prognosis.

Antigen detection for human immunodeficiency virus

“…This suggests the use of HIV antigen EIA as a prognostic index in assessing disease progression. In a group of 96 hemophiliacs, a much higher incidence of AIDS was observed in those individuals who were positive for HIV antigen (2). Moreover, antigen titers tended to increase with disease progression.…”

“…HIV Antigen as a Predictive Marker A strong correlation has been established between the onset of antigenemia and the progression of disease after seroconversion (2,19,24,29,30,38,42,45,47,50,53,61). This suggests the use of HIV antigen EIA as a prognostic index in assessing disease progression.…”

“…It is difficult to envision an immune regulatory mechanism that selectively inhibits only one among the several antibodies to HIV produced. Furthermore, it has been observed that some patients with high antigen levels also lack antibody to p55, the undegraded gag precursor polyprotein from which p24 is ultimately processed (2,28). Thus, the reduction in antibody appears not to be totally selective for anti-p24.…”

Combined use of an immunotoxin and cyclosporine to prevent both activated and quiescent peripheral blood T cells from producing type 1 human immunodeficiency virus.

“…Concentrations of p24 antigen in the cell supernatants were measured by using a commercially available immunoassay (Coulter) (35). The limit of detection of this assay is 25 pg/ml.…”

Overproduction, Purification, and Diagnostic Use of the Recombinant HIV‐1 Gag Proteins, the Precursor Protein p55 and the Processed Products p17, p24, and p15

“…The primary seroconversion marker is the appearance of antibodies to envelope glycoproteins and p24 core protein. Disease progression is marked by a decline in CD4+ cell number (7,13,17), reappearance of antigenaemia, and a decline in the levels of antibodies to core proteins (4,35). The p24 antigenaemia along with a decline in the level of antibodies to p24 has been considered to be one of the useful prognostic markers (4,14,35,36,40).…”