Search PubMed⌕ Search

Biomedical subjects

F de Wolf

Publications and source records attributed to F de Wolf.

116 records · Page 7Linked to original sources
PubMed1987

Decline of antibody reactivity to outer viral core protein p17 is an earlier serological marker of disease progression in human immunodeficiency virus infection than anti-p24 decline.

Using a modified immunoblot procedure we looked for early serological markers of disease progression in sequential serum samples from 30 initially symptomless HIV-infected homosexual men. Sixteen men who did not progress beyond persistent generalized lymphadenopathy (PGL) and did not develop HIV antigenaemia showed persistent strong immunoglobulin G (IgG) reactivity to all initially recognized HIV proteins. Three out of four men who did not progress beyond PGL but did develop HIV antigenaemia showed declining or absent IgG reactivity to the outer HIV core protein p17, whereas reactivity to other initially recognized HIV proteins persisted in all four; in one of these subjects a striking decline in anti-p17 reactivity occurred 1 1/2 months after HIV antibody seroconversion and 7 1/2 months before HIV antigenaemia developed. In nine out of 10 men who developed constitutional disease [Centers for Disease Control (CDC) group IV A] or AIDS (CDC groups IV C1 and IV D), a decline in anti-p17 reactivity was seen preceding or at disease development; in two of these men a concomitant decline in anti-p24 reactivity was seen. In the only individual without HIV antigenaemia who developed CDC group IV disease, anti-p17 reactivity declined 10 months before disease development, whereas no similar decline in anti-p24 reactivity was seen. Decline in IgG antibody reactivity to HIV core protein p17 appears to be an earlier marker of disease progression than the previously reported decline in anti-p24 reactivity, and may be of value in selecting individuals for secondary prevention of HIV-related disease development.

AIDS-Related Complex↗
PubMed1986

Persistent HIV antigenaemia and decline of HIV core antibodies associated with transition to AIDS.

Sequential serum samples from 13 homosexual men who seroconverted for antibodies to human immunodeficiency virus (HIV) were tested for HIV antigen. In one of these men, who developed the acquired immune deficiency syndrome (AIDS), HIV antigenaemia preceded the onset of AIDS by more than a year and persisted throughout the course of the disease. This antigenaemia was accompanied by the disappearance of IgG antibody reactivity to the major HIV core protein p24. In none of the 12 others, who all remained without serious disease, were serum concentrations of HIV antigen detected, except on one occasion in one man. All their serum samples showed strong IgG antibody reactivity to p24. Nine children who were infected with HIV in 1981 by plasma transfusion from a single donor were also followed up for HIV antigenaemia. HIV antigen was almost constantly present in the serum (26 of 28 samples) of five children who developed AIDS related complex or AIDS and less often in the serum (four of 10 samples) of four children who remained free of symptoms. The two children who developed AIDS showed a virtual absence of antibody reactivity to p24. These results indicate that increased HIV gene expression is a contributing factor to the development of AIDS and also provide evidence for a switch from latent to active HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Expression of human immunodeficiency virus antigen (HIV-Ag) in serum and cerebrospinal fluid during acute and chronic infection.

Human immunodeficiency virus antigen (HIV-Ag) was detected in the serum of most adult (13/16) and paediatric (6/6) AIDS patients and rarely in the serum of symptomless seropositive controls (1/13). It was present in the cerebrospinal fluid (CSF) of all 5 children and most (5/9) adults with AIDS-related encephalopathy, but not in the CSF of 13 symptomless seropositive controls, of whom 8 had antibody in the CSF. A longitudinal study of 1 of the controls with antibody in the CSF showed that HIV-Ag in CSF was present transiently before the occurrence of antibody in the CSF. In serial samples of serum from 35 men who seroconverted HIV-Ag was detected in 11 persons--in 5 before seroconversion and in 6 after. 3 of the 6 who became antigenaemic after seroconversion remained so for the rest of the follow-up. AIDS was diagnosed in 1 patient, 3 months after HIV-Ag was first detected in serum and 6 months after seroconversion. The findings suggest that HIV-Ag appears early and transiently in primary HIV infection. Antibody production follows, after which HIV-Ag may disappear. Its persistence or reappearance seems to correlate with clinical, immunological, and neurological deterioration.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Antibody recognition of amino acid divergence within an HIV-1 neutralization epitope.

Antibodies elicited by HIV-1 strains, and which neutralize such strains in vitro, bind to synthetic peptides of 5-8 amino acids in length. These amino acids, although variable, have a fixed location between two cysteines in the carboxyl terminus of the HIV-1 external envelope. Nine peptides of 9 amino acids corresponding to the gp120 domains of European and American (LAV-1, NY5, CDC4, SF2), Haitian (RF) and African (ELI, MAL, Z3, Z6) HIV-1 strains, were synthesized using LAV-1 and RF neutralization epitopes as models. Serum of chimpanzees infected with LAV-1, HTLV-IIIB or HTLV-IIIRF reacted predominantly with the homologous peptide, although cross-reactivity with heterologous peptides occurred: 8 out of 11 human sera with HTLV-IIIB-neutralizing activity bound the LAV-1/HTLV-IIIB peptide, and 6 out of 7 sera with HTLV-IIIRF-neutralizing activity bound the RF peptide. African sera reacted most frequently with the Z3 peptide (78%) while only 35% (p = 0.0001) of European and 20% (p less than 0.0001) of American sera recognized it. Recognition patterns of children from the USA and Europe were different. Although multiple reactivities were observed, blocking experiments favoured cross-reactivity as the explanation. Based on the antibody profiles of nonapeptide recognition, peptides LAV-1, RF and SF2 were clustered, as were NY5 and CDC4, and so were Z6, MAL and ELI. This antigenic relatedness of HIV-1 strains could not entirely be explained by the physico-chemical characteristics of the nonamers per se. Resemblance was observed with the clustering of HIV-1 strains based on the divergence of the nucleotide sequence of entire HIV-1 envelopes. This implies a role of peripheral envelope residues, in the context of infectious particles or infected cells, in determining the specificity of antibodies reactive to the V3 domain. Therefore, the neutralization domain in this variable region may be considered part of a conformational structure involving several envelope regions which appear distinct from each other in the primary sequence.

Amino Acids↗