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Biomedical subjects

J Goudsmit

Publications and source records attributed to J Goudsmit.

At least 289 records · Page 16Linked to original sources
PubMed1990

Evidence for rapid selection and deletion of HIV-1 subpopulations in vivo by V3-specific neutralizing antibody: a model of humoral-associated selection.

Emergence in two chimpanzees of HIV-1 HTLV-IIIB variants resistant to neutralization by the pre-existing antibody is described. Viruses isolated from the HTLV-IIIB gp120 vaccinated and challenged animal were more resistant to neutralization, had more heterogenic genomes and showed more pronounced antigenic drift as determined by serotypic neutralization analysis than viruses isolated from the naive infected animal, indicating immune pressure as the selective mechanism. The earliest selecting antibody population detected in the chimpanzees appeared to be conformationally dependent. This was demonstrated by its ability to neutralize only the most replication-competent sub-populations of the HTLV-IIIB inoculum strain, yet was found to bind a HTLV-IIIB common nonapeptide (IQRGPGRAF) derived from the gp120 isolate-specific 3rd variable domain (V3) also known to induce isolate-specific neutralization in multiple species. Each of the recovered isolates had become resistant to neutralization by both a monoclonal (0.5 beta) and polyclonal HTLV-IIIB gp120 V3-specific antibody by as much as 16 to 256-fold. Amplification of the V3 coding sequence by polymerase chain reaction and subsequent sequence analysis of the neutralization-resistant variants obtained from in vivo infected animals indicated that resistance to neutralization was conferred by changes outside the direct binding site for the selective neutralizing antibody. Further studies indicated that apparent neutralization-resistant variants, yielded after in vitro passage through chimpanzee and human peripheral blood mononuclear cell cultures void of HIV-specific antibody, result from the homogenic amplification of the more replication competent sub-population pre-existing in the original viral stock. These faster replicating sub-populations appear to dominate initially and therefore are the initial prime targets recognized by the chimpanzee humoral immune system upon infection in vivo and thus eliminated. The described finding of virus escape due to a conformationally-induced flexibility of the major neutralization epitope termed "conformational-V3 hypervariability", coupled to the known primary amino acid hypervariability of this epitope (V3) termed "linear-V3 hypervariability", may be all that is required by the virus to survive in an otherwise effective humoral immune system.

Amino Acid Sequence↗
PubMed1990

Detection and characterization of HIV-1 by polymerase chain reaction.

Recently a new technique, the polymerase chain reaction (PCR), has been used for the detection and characterization of HIV-1 proviral DNA and viral RNA. These reports support the notion that the PCR is more sensitive and specific than other established HIV-1 detection techniques. However, due to its extreme sensitivity, the PCR is highly susceptible to contamination, resulting in false positive results. To avoid contamination, strict rules on sample preparation and pre- and post-PCR handling are required. Confirmation of both positive and negative PCR results by independent techniques is not always feasible, and, therefore, optimal PCR conditions, inclusion of control samples, repetition of results, and confirmation of specificity by hybridization are required. The choice of the material from which HIV-1 is amplified, the primers used for amplification as well as the PCR conditions will determine what is actually amplified.

Amino Acid Sequence↗
PubMed1989

Declining incidence of AIDS dementia complex after introduction of zidovudine treatment.

OBJECTIVE: To assess the incidence of the AIDS dementia complex and the presence of HIV I p24 antigen in cerebrospinal fluid in relation to zidovudine treatment. DESIGN: Retrospective study of a consecutive series of patients with AIDS from 1982 to 1988. SETTING: An academic centre for AIDS. PATIENTS: 196 Patients with AIDS and neurological symptoms examined from 1982 to 1988. INTERVENTIONS: Zidovudine treatment, which was introduced to The Netherlands on 1 May 1987 for patients with severe symptoms of HIV infection (Centers for Disease Control groups IVA, B, C, and D). MAIN OUTCOME MEASURES: Diagnosis of AIDS dementia complex and presence of HIV I p24 antigen in cerebrospinal fluid. RESULTS: The AIDS dementia complex was diagnosed in 40 of the 196 (20%) patients with AIDS. Thirty eight of 107 patients with AIDS (36%) not taking zidovudine developed the AIDS dementia complex compared with two of the 89 (2%) taking the drug (p less than 0.00001). The incidence of the AIDS dementia complex increased to 53% in the first half of 1987, after the introduction of zidovudine in May 1987, decreasing to 10% in the second half of 1987 and to 3% in 1988. Dementia was diagnosed before definition of the AIDS dementia complex (1986) according to DSM-III criteria and there was good agreement between diagnosis before and after 1986. Sixteen of 61 samples of cerebrospinal fluid (26%) from patients with AIDS (10 with the AIDS dementia complex) not taking zidovudine were positive for HIV I p24 antigen, whereas none of 37 cerebrospinal fluid samples from patients with AIDS (two with the AIDS dementia complex) taking zidovudine were positive. CONCLUSIONS: The incidence of AIDS dementia complex in patients with AIDS declined after the introduction of systematic treatment with zidovudine; the AIDS dementia complex might be prevented by inhibiting viral replication in the central nervous system.

AIDS Dementia Complex↗
PubMed1989

Association between biological properties of human immunodeficiency virus variants and risk for AIDS and AIDS mortality.

49 individuals seropositive for human immunodeficiency virus (HIV) antibody were studied longitudinally for the relation between in-vitro properties of their sequential HIV isolates and clinical course before and after the development of AIDS. They were classified into three groups according to the syncytium-inducing capacity, replication rate, and host range of their HIV isolates. The most rapid progression to AIDS (median 15 months) and the lowest survival rate following AIDS diagnosis (median survival 12.5 months) were observed in individuals with high-replicating, syncytium-inducing HIV isolates, followed by individuals with high-replicating, non-syncytium-inducing isolates. In contrast, most individuals with low-replicating, non-syncytium-inducing HIV isolates remained symptom-free during the study period (median follow-up until AIDS diagnosis greater than 42 months), and the few individuals from this group in whom AIDS developed were still alive at the end of the study period (median survival greater than 34 months). In addition, AIDS patients from the three groups differed with respect to their symptoms. Zidovudine treatment in the symptom-free period seemed to delay the onset of AIDS in all risk groups, although stabilisation of CD4+ cell numbers was observed only in individuals with non-syncytium-inducing HIV variants.

Acquired Immunodeficiency Syndrome↗
PubMed1989

[Decreased incidence in HIV infection and changed sex behavior in a cohort of homosexual men in Amsterdam].

Prevalence and incidence of HIV were studied in two cohorts of homosexual men in Amsterdam between 1980 and 1987. The cumulative incidence of HIV infection increased from a weighted 2.2% in 1980 to 39% in 1987. In that year the observed incidence was less than 1%. The estimated annual HIV incidence was 3% in 1981, rose to 8.8% in 1984 and decreased gradually to 0% in 1987. This decline was assumed to be linked to a strong reduction of high risk sexual behaviour among the men under study.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Changes in sexual behaviour and the fall in incidence of HIV infection among homosexual men.

To investigate the epidemiology and normal course of infection with HIV the prevalence and incidence of the infection were studied among two cohorts of homosexual men in Amsterdam in 1980-7. The cumulative incidence of infection increased from a weighted 2.2% in 1980 to 39.0% in 1987. The estimated yearly incidence of HIV was 3.0% in 1981, rose to 8.8% in 1984, and fell gradually to 0% in 1987. During the study the sexual behaviour of the cohorts was examined. The number of men with whom anopenetrative intercourse was practised fell from a mean of 10.6 to 1.4 for those positive for HIV antibody, whereas the number with whom anoreceptive intercourse was practised fell from a mean of 3.7 to 0.5 for those negative for the antibody. In addition, there was a reduction in the number of cases of hepatitis B and syphilis among men in general. The decline in infection with HIV was assumed to be linked to changes in sexual behaviour. Such changes practised early in the course of the epidemic probably had a strong effect on the number of cases of AIDS among homosexual men in Amsterdam.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Human immunodeficiency virus type 1 antigen in cerebrospinal fluid. Correlation with clinical neurologic status.

Human immunodeficiency virus type-1 (HIV-1) antigen was assayed in paired serum/cerebrospinal fluid (CSF) specimen from 85 adults and 58 children with acquired immunodeficiency syndrome and was compared with clinical neurological status. A quantitative comparison of HIV-1 antigen levels in matched serum and CSF specimens indicated that HIV-1 antigen expression in these compartments is independent and is correlated with acquired immunodeficiency syndrome dementia complex in adults and progressive encephalopathy in children. In a longitudinal study (n = 47), 16 patients tested positive for HIV-1 antigen in the CSF before (n = 2) or coincident (n = 14) with neurological deterioration. Six patients who tested positive for HIV-1 antigen in the CSF remained neurologically normal for a median duration of follow-up of 11 months. Six of 25 patients who tested negative for HIV-1 antigen in the CSF, subsequently showed neurological deterioration. These data indicate that HIV-1 antigen expression in the CSF is not useful in predicting neurological deterioration.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Longitudinal study of leukocyte functions in homosexual men seroconverted for HIV: rapid and persistent loss of B cell function after HIV infection.

The early effects of infection with human immunodeficiency virus (HIV) were investigated in homosexual men who had seroconverted for anti-HIV antibodies. Leukocyte functional activities were determined in longitudinally collected peripheral blood mononuclear cell samples. During the first 10 months following seroconversion, anti-CD3 monoclonal antibody-induced T cell proliferation, monocyte accessory function and T helper activity on B cell differentiation in a pokeweed mitogen-driven system were not affected. In contrast, from the moment of seroconversion on, B cells of seroconverted men failed to produce immunoglobulin in the pokeweed mitogen-driven system. This defect was not restored by addition of normal CD4+ T cells. Immunoglobulin synthesis induced by Staphylococcus aureus and interleukin 2 decreased gradually, until it was completely lost 10 months after seroconversion. In addition, proliferation in response to anti-IgM or Staphylococcus aureus by B cells from HIV seroconverted men was decreased. The lack of inducible in vitro B cell activity was not accompanied by elevated spontaneous Ig synthesis by B cells of the seroconverted men. In the second group of men studied during the 2nd year following seroconversion, T helper activity on normal B cell differentiation significantly decreased, whereas anti-CD3-induced T cell proliferation and monocyte accessory function were not significantly affected. Our results demonstrate that in almost all HIV-infected individuals B cell functional defects are the first leukocyte abnormalities observed preceding defects in T helper activity.

Antibody Formation↗
PubMed1989

Markers for progression to acquired immune deficiency syndrome and zidovudine treatment of asymptomatic patients.

Eighteen asymptomatic men with persistent human immunodeficiency virus type I (HIV-I) p24 antigenaemia were treated with zidovudine 250-500 mg (+/- acyclovir 800 mg) 6-hourly for 4-12 weeks, and subsequently with zidovudine 500 mg (+/- acyclovir 1600 mg) 12-hourly for 36 weeks. After 24 weeks six additional HIV antigenaemic subjects were entered and treated directly with zidovudine 500 mg 12-hourly. Over the treatment period serum HIV-I p24 (HIV-Ag) levels declined in all 24 subjects; significantly so in 17, and to below cut-off values in five. Mean serum HIV-Ag levels in different treatment groups declined in 68-78%. Initial increases in CD4+ cell counts were not sustained. Over 48 weeks serum HIV-Ag levels rose in three out of five non-treated men with persistent HIV antigenaemia, and they slightly declined in two; the mean serum HIV-Ag level in this group rose 67%. Regression of enlarged lymph nodes was seen in 19 out of 19 of the zidovudine-treated subjects. In the 24 zidovudine-treated subjects no disease progression occurred during follow-up, whereas two out of five non-treated men went on to develop CDC group IV A, and IV C-2 disease, respectively. Adverse reactions to the study drugs were infrequent and mild. Anaemia caused symptoms in two, but serious leucopenia or neutropenia was not observed. An initial positive effect on thrombocyte numbers was not sustained. These data demonstrate that in asymptomatic HIV-infected subjects zidovudine 500 mg 12-hourly is well tolerated and has a persistent inhibitory effect on viral replication.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Serum capacity to inhibit reverse transcriptase in vitro distinguishes HIV-1 infection from HIV-2 or SIV infection.

The inhibition of HIV-1 and SIV reverse transcriptase by human and rhesus macaque serum positive for HIV-1 or HIV-2/SIV antibodies was studied. The domain to which reverse transcriptase-inhibiting antibodies were elicited appeared to be highly antigenic. A total of 67% (48 of 72) of individuals had HIV-1 reverse transcriptase-inhibiting (RTI) antibodies 1 year after seroconversion for HIV-1, 90% (9 of 10) of HIV-2 antibody positive persons had SIV RTI antibodies, and all four experimentally SIV-infected rhesus macaques developed SIV RTI antibodies. Low cross-reactivity between HIV-1 and HIV-2/SIV RTI antibodies was observed. Of 10 HIV-1 RTI sera, 2 reduced SIV RT activity by more than 50% (mean reduction 85 versus 24%). Only 1 of 9 SIV RTI human sera reduced HIV-1 RT (mean reduction 74 versus 25%). This serum, however, showed a shared reactivity against both HIV-1 and HIV-2. These results indicate that the HIV-1 domain inducing RTI antibodies is antigenically different from the HIV-2/SIV domain.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Low antigenicity of HIV-1 rev: rev-specific antibody response of limited value as correlate of rev gene expression and disease progression.

An enzyme immunoassay based on an E. coli-produced HIV-1 rev gene product was used to detect rev-specific antibodies in longitudinally collected serum samples from 196 initially symptom-free men who were seropositive for antibodies to HIV-1 structural proteins and 72 men who seroconverted for such antibodies. In 61% of men no rev-specific antibodies were detected at all, 30% had persistently detectable rev-specific antibodies, and in 9% rev-specific antibodies were only transiently or intermittently detected. When a persistent rev-specific antibody response occurred in subjects who seroconverted to structural proteins, it was always, with one exception, found within 12 months of seroconversion. The rev-specific antibodies were also studied in a transectional sample of sera from the men who remained symptom-free and from those who developed AIDS-related conditions or AIDS, as well as in sera from 31 other men with AIDS-related conditions and in sera from 6 of these men at the time they developed AIDS. The rev-specific antibodies were found in 34% of symptom-free men, in 28% of patients with AIDS-related conditions, and in 16% of patients with AIDS. The low incidence of rev-specific antibodies early after infection may be due to low antigenicity of rev. The lower prevalence of rev-specific antibodies in sera from patients with AIDS, compared with patients with AIDS-related conditions and symptom-free HIV-1-infected individuals, may be explained by a progressive HIV-1-induced immunodeficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1989

Effect of human immunodeficiency virus (HIV) antibody knowledge on high-risk sexual behavior with steady and nonsteady sexual partners among homosexual men.

For the study of the impact of human immunodeficiency virus (HIV) antibody testing on high-risk sexual behavior with nonsteady and steady sexual partners, 307 homosexual men (118 seronegative, 75 seropositive, and 114 untested) were interviewed at three consecutive six-month intervals between July 1985 and December 1986. From the results, it appears that among seropositives the percentage who performed anogenital insertive intercourse with nonsteady partners remained constant (73, 64, and 61% during the first, second, and third intervals, respectively (nonsignificant]. Among seronegatives and those who were untested, the percentages who practiced anogenital receptive intercourse with nonsteady partners decreased from 44 to 29% and from 54 to 20%, respectively (p less than 0.05). The percentage who performed anogenital insertive intercourse and anogenital receptive intercourse with their steady partner remained constant in all groups: seropositives, +/- 70%; seronegatives, +/- 60%; and untested, +/- 55%. Seropositives were more likely to use condoms during anogenital insertive intercourse with their nonsteady and steady sexual partners than were seronegatives and untested persons during anogenital receptive intercourse with these partners (p less than 0.05). In the majority of cases, condoms were not used antibody testing in the three groups studied. The generalizability of these results, however, is limited.

Adult↗
PubMed1989

Antibody response to a synthetic peptide covering a LAV-1/HTLV-IIIB neutralization epitope and disease progression.

Sequential sera of homosexual men participating in a prospective study on the incidence of HIV-1 infection and risk factors for AIDS were tested for the presence of antibodies to a synthetic 17-mer (Neu21; KSIRIQRGPGRAFVTIG) representing a neutralization epitope as present on the LAV-1/HTLV-IIIB strain of HIV-1. Of 191 at entry, 143 (75%) HIV-1-seropositive men remained anti-Neu21-negative during the follow-up period of 36 months. Thirty-seven (19%) HIV-1-seropositive men were persistently anti-Neu21-positive. Eleven (6%) HIV-1 seropositive men seroconverted for anti-Neu21 during follow-up. Of 75 men developing antibodies to HIV-1, 17 (23%) developed antibodies to Neu21. The incidence of anti-Neu21 seroconversion (calculated as attack rate) after 36 months was significantly lower (P less than 0.00001) among HIV-1-seropositive individuals (8%) than among the 75 HIV-1 seroconverters tested (25%), indicating that seroconversion to this neutralization domain occurs early during infection. AIDS and AIDS-related complex were diagnosed in 17% of the anti-Neu21 negatives and in 11% of the anti-Neu21 positives; this difference was not significant. The presence of HIV-1 antigen (29 versus 28%), the absence of antibodies to core proteins (45 versus 46%) and low CD4+ cell numbers (34 versus 40%) were not seen more frequently among anti-Neu21 negatives than among anti-Neu21 positives. These results argue against a role for antibodies to this LAV-1/HTLV-IIIB neutralization domain in protection against disease progression.

Adult↗