Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “HIV”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources

Evaluation of a new fourth generation enzyme-linked immunosorbent assay, the LG HIV Ag-Ab Plus, with a combined HIV p24 antigen and anti-HIV-1/2/O screening test.

The LG HIV Ag-Ab Plus, a new fourth generation diagnostic assay for HIV infection, was evaluated in comparison to the Enzygnost HIV Integral, an established fourth generation HIV assay. The LG assay showed 100% sensitivity with 109 samples with anti-HIV-1, anti-HIV-2 or anti-HIV-1 group O reactivity. It also detected correctly all 51 positives on three BBI performance panels, slightly outperforming the Enzygnost HIV Integral, which detected 50. The specificity of the LG HIV Ag-Ab Plus was 99.9% with 999 sera from healthy blood donors, which was slightly inferior to the performance of the Enzygnost HIV Integral, which had 100% specificity. The LG assay showed 100% specificity with 81 specimens with underlying diseases including hepatitis B, demonstrating a low risk of cross-reactivity with other infections. The reduction of the diagnostic window by the LG HIV Ag-Ab Plus, compared to a third generation HIV assay, was 6.3 days. The LG assay also showed sufficiently high intra-person and inter-person reproducibility. The overall performance of this new fourth generation HIV assay was adequate for screening and diagnosis of HIV infection.

AIDS Serodiagnosis↗

Actual versus perceived HIV status, sexual behaviors and predictors of unprotected sex among young gay and bisexual men who identify as HIV-negative, HIV-positive and untested.

OBJECTIVES: To compare the prevalence and predictors of HIV sexual risk behavior among young gay and bisexual men who perceived themselves to be HIV-negative, HIV-positive, or who were untested. DESIGN: Population-based sample of young gay and bisexual men. METHODS: Using multi-stage probability sampling, 408 gay and bisexual men aged 18-29 years in San Francisco were recruited and interviewed, and blood samples for HIV-testing from 364 participants were obtained. RESULTS: HIV prevalence was 18.7%, although 25% of the men who were HIV-positive did not know it. Thirty-seven per cent reported engaging in unprotected anal intercourse during the past year, including 59% of the men who knew they were HIV-positive, 35% of the men who perceived themselves HIV-negative and 28% of the untested men. Logistic regressions found similar predictors of unprotected intercourse for HIV-negatives and HIV-positives, including sexual impulsivity, substance use, sexual enjoyment and communication problems. CONCLUSIONS: The high rates of unprotected intercourse, particularly among the HIV-positive men, attest to the urgent need for HIV-prevention interventions for young gay and bisexual men. The findings suggest that many of the important variables to target in interventions are similar for both HIV-positive and HIV-negative men.

Adolescent↗

HIV-specific IgG in cervicovaginal secretions of exposed HIV-uninfected female sexual partners of HIV-infected men.

The presence of human immunodeficiency virus (HIV)-specific antibodies was examined in plasma and cervicovaginal (mucosal) samples of 24 HIV-exposed uninfected (EU) female sexual partners of HIV-infected men, and compared with findings in 18 HIV-infected and 15 low-risk HIV-uninfected women. Only HIV-infected women had detectable HIV-specific immunoglobulin G (IgG) (18 of 18) or HIV-IgA (6 of 18) in cervicovaginal samples by enzyme immunoassay (EIA). However, 3 of 24 EU women had positive Western blot (WB) for HIV-IgG in cervicovaginal secretions, while 2 of 24 EU women and 1 of 15 low-risk controls had indeterminate IgG-WB. EU women with positive or indeterminate IgG-WB in the cervicovaginal samples were similar in risk to the remaining EU women. None of the HIV-uninfected women had mucosal HIV-IgA. The findings suggest that some sexually or parenterally exposed HIV-uninfected women might develop low-level mucosal IgG responses. However, it appears unlikely that HIV-specific cervicovaginal antibodies play a major role in protection from HIV infection in this EU population.

AIDS Serodiagnosis↗

HIV-1, HIV-2, HTLV-I/II and Treponema pallidum infections: incidence, prevalence, and HIV-2-associated mortality in an occupational cohort in Guinea-Bissau.

The prevalence and incidence of human immunodeficiency virus types 1 and 2 (HIV-1, HIV-2), human T-lymphotropic virus types I and II (HTLV-I/II), and syphilitic infections and the association between these infections were determined in a cohort of police officers in Guinea-Bissau. Between January 1990 and December 1992, 1,384 subjects (1,241 men and 143 women) were included in the study; and of the first 879 tested, 561 were tested at least for a second time. The overall seroprevalence of HIV-1 was 0.4%, of HIV-2 11.6%, and of HTLV I/II 4.4%. Three individuals (0.2%) were seropositive for both HIV-1 and HIV-2. Women had a significantly higher prevalence of HIV-2 infection than men (16.8% and 11.0%, respectively, p < 0.05). Serologic evidence of previous syphilis was present in 12.1% and was significantly more common in men (12.7%) than in women (7.0%) (p < 0.05). There was a significant association between the prevalence of HIV-2 and HTLV-I/II infection (p < 0.05). The annual incidence of HIV-1 was 0.7%, of HIV-2 1.6%, of HTLV I/II 0.4%, and of syphilis 1.7%. There was no association between the incidence of the various infections. The death rate (per 100 person-years) was significantly higher among HIV-2-infected individuals (2.7%) than among HIV-negative individuals (0.5%) (relative risk = 5.1; 95% confidence interval, 2.1-12.2; p < 0.001). HIV-related symptoms were more frequent among the HIV-2-positive individuals who died compared with the seronegative individuals who died (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Beta 2-microglobulin, HIV-1 p24 antibody and acid-dissociated HIV-1 p24 antigen levels: predictive markers for vertical transmission of HIV-1 in pregnant Ugandan women.

OBJECTIVES: To evaluate the clinical utility of plasma beta 2-microglobulin (beta 2M) levels, acid-dissociated HIV-1 p24 antigen, and HIV-1 p24-antibody titers in predicting HIV-1 vertical transmission in 227 HIV-1-infected Ugandan pregnant women. DESIGN: Plasma beta 2M levels, acid-dissociated HIV-1 p24-antigen positivity, and HIV-1 p24-antibody titers were determined using commercial enzyme immunoassays (EIA) in a Ugandan cohort of 52 HIV-1-seropositive transmitting mothers, 175 HIV-1-seropositive non-transmitting mothers, and 52 seronegative mothers within 6 weeks prior to delivery. RESULTS: Transmitter mothers had significantly higher plasma concentrations of beta 2M (1.80 +/- 1.13 mg/l) than non-transmitter seropositive mothers (1.32 +/- 0.81 mg/l; P = 0.0013). Similarly, a significantly higher proportion of transmitter mothers had detectable p24 antigen than non-transmitter mothers [six out of 51 (11.8%) versus six out of 173 (3.5%); P = 0.03]. Compared with the vertical transmission rate of 23% in the seropositive group, the positive predictive values of a beta 2M level > 1.5 mg/l or detectable HIV-1 p24 antigen for vertical transmission were 34 and 50%, respectively. Five of six (83.3%) seropositive mothers with both a beta 2M level > 1.5 mg/l and detectable p24 antigenemia transmitted HIV-1 infection to their infants compared with 25 of 124 (20.2%) seropositive mothers with values below the cut-off values for both tests (P = 0.00249). However, beta 2M was not found to be a significant independent predictor of vertical transmission when analyzed in a multivariate model with p24 antigenemia. There was no significant difference in HIV-1 p24-antibody titers in transmitter mothers versus non-transmitter mothers (P = 0.299). CONCLUSION: beta 2M levels and acid-dissociated HIV-1 p24-antigen assays may be used to predict which HIV-1-infected pregnant women are at greatest risk for vertical transmission. However, only the p24-antigen test was independently predictive of vertical transmission and its clinical utility is limited.

Adolescent↗

A vector system for introducing foreign HIV-1 env genes and pseudotyping of MuLV particles with the recombinant HIV-1 envelope proteins for anti-HIV-1 assay.

We attempted to incorporate the HIV-1 envelope proteins derived from various HIV-1 strains into MuLV particles for developing a rapid and safe anti-HIV-1 screening system. In a previous study, only HIV-1 envelope protein lacking cytoplasmic 144 amino acids has been reported to be able to incorporate into MuLV particles. We designed and constructed a vector, pcKCX, expressing the envelope glycoprotein with cytoplasmic truncation by introducing the partial foreign HIV-1 env gene corresponding to the ectodomain of its envelope protein. Three HIV-1 env genes of AD8, BaL or 89.6 strains were cloned, and the HIV-1/MuLV pseudotypes were generated in the transfected TELCeB6 cells with all the cloned plasmids. The pseudotypes displayed host specificity depending on their original HIV-1 strains and their infection to the target cells was inhibited by treatment of a potent anti-HIV-1 peptide C34. A stable cell clone against the HIV-1(BaL) strain was found to express the R5 tropic envelope glycoprotein on the cell surface and to produce continuously HIV-1(BaL)/MuLV pseudotypes. These results suggested that the vector system is useful for cloning of various foreign HIV-1 env genes and the recombinant envelope glycoproteins effectively incorporate into MuLV particles. The HIV-1/MuLV pseudotypes may be useful for anti-HIV-1 assay.

Cell Line↗

Detection of HIV antigen and specific antibodies to HIV core and envelope proteins in sera of patients with HIV infection.

The sera of well-characterized populations were examined for three markers of human immunodeficiency virus (HIV) infection; HIV antigen (HIV Ag), and antibodies to HIV envelope (gp41) and core (p24) proteins. Of 563 serum samples tested, 251 were from HIV-infected patients diagnosed as having AIDS manifested by opportunistic infections (AIDS-OI), AIDS-associated Kaposi's sarcoma (AIDS-KS), or AIDS-related complex (ARC). One hundred seventy-six specimens tested were from asymptomatic high-risk individuals, and 136 were from heterosexual control subjects or patients with non-AIDS-related disease. None of the 136 control individuals tested had HIV Ag or HIV antibodies to either p24 or gp41. Of the 427 HIV-seropositive individuals, 99% to 100% were positive for gp41 antibodies to HIV. In contrast, the seroprevalence of p24 antibodies to HIV varied from 23% to 83% and appeared to be inversely associated with the severity of the patients' clinical symptoms. When specimens were analyzed for the presence of HIV Ag, in seropositive individuals the prevalence rate for this marker was lowest (1.4%) in asymptomatic individuals and highest (50%) in the AIDS-OI diagnosed group. Also, 240 cases with AIDS-KS, AIDS-OI, and ARC and the group of asymptomatic high-risk individuals were analyzed for T helper/T lymphocytes (T4) cell number and T4/T8 ratio; only one (2.0%) HIV Ag-positive case showed a T4 cell number greater than 400 and a normal T4/T8 ratio. These studies appear to demonstrate a direct correlation between the presence of HIV Ag and the severity of clinical complications of HIV infection.

Antibodies, Viral↗

Serum HIV-1 p24 antibody, HIV-1 RNA copy number and CD4 lymphocyte percentage are independently associated with risk of mortality in HIV-1-infected children. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group.

OBJECTIVE: The role of HIV-1 antibody in modulating disease progression must be assessed in the context of other immune and viral load markers. We evaluated the association between HIV-1 p24 antibody, HIV-1 RNA, immune complex-dissociated (ICD) p24 antigen, CD4 cell percentage, and mortality in a cohort of 218 HIV-infected children enrolled in a trial of intravenous immunoglobulin prophylaxis of bacterial infections. METHODS: CD4 cell percentage was measured and sera collected and stored at baseline and every 3 months on study (1988-1991). Stored sera were assayed for HIV-1 p24 antibody, HIV-1 RNA, and ICD p24 antigen. Mortality was recorded during the trial and updated through 1996 (mean total follow-up, 6.3 years). RESULTS: Eighty-one (37%) children died; probability of mortality for children with baseline HIV-1 p24 antibody concentrations of undetectable (< 1), 1-4, 5-124, and > or = 125 reciprocal titer units (RTU) was 61, 50, 24, and 10%, respectively. A 3.5-fold increase in the relative risk (RR) of death [95% confidence interval (CI), 2.2-5.5] was observed among children with baseline HIV-1 p24 antibody concentration < 5 RTU compared with > or = 5 RTU. In multivariate analyses, p24 antibody, HIV-1 RNA, and CD4 cell percentage but not ICD p24 antigen were independently associated with mortality; the RR of death increased by 1.7 (95% CI, 1.3-2.1) for each log10 decrement in baseline HIV-1 p24 antibody. CONCLUSIONS: HIV-1 p24 antibody, HIV-1 RNA and CD4 cell percentage independently predict mortality amongst infected children. Whereas CD4 cell percentage provides an estimate of the general degree of immune suppression, HIV-1 p24 antibody could provide an easily obtained, inexpensive assessment of CD4 cell function and could augment prognostic information provided by CD4 cell count and viral load for clinical management of infected children.

CD4 Lymphocyte Count↗

Synthetic HIV-2 protease cleaves the GAG precursor of HIV-1 with the same specificity as HIV-1 protease.

A 99-amino acid protein having the deduced sequence of the protease from human immunodeficiency virus type 2 (HIV-2) was synthesized by the solid phase method and tested for specificity. The folded peptide catalyzes specific processing of a recombinant 43-kDa GAG precursor protein (F-16) of HIV-1. Although the protease of HIV-2 shares only 48% amino acid identity with that of HIV-1, the HIV-2 enzyme exhibits the same specificity toward the HIV-1 GAG precursor. Fragments of 34, 32, 24, 10, and 9 kDa were generated from F-16 GAG incubated with the protease. N-terminal amino acid sequence analysis of proteolytic fragments indicate that cleavage sites recognized by HIV-2 protease are identical to those of HIV-1 protease. The verified cleavage sites in F-16 GAG appear to be processed independently, as indicated by the formation of the intermediate fragments P32 and P34 in nearly equal ratios. The site nearest the amino terminus is quite conserved between the two viral GAG proteins (...VSQNY-PIVQN...in HIV-1,...KGGNY-PVQHV...in HIV-2). In contrast, the putative second site (...IPFAA-AQQKG...) of HIV-2 GAG shares minimal sequence identity with site 2 of HIV-1 GAG (...SATIM-MQRGN...). These sequence variations in the substrates suggest higher order structural features that may influence recognition by the proteases. Pepstatin A inhibits HIV-2 protease, whereas 1,10-phenanthroline and phenylmethylsulfonylfluoride do not; these results are in agreement with the finding that proteases of HIV and other retroviruses are aspartyl proteases.

Amino Acid Sequence↗

Protective correlates against HIVs may have evolved in human populations in the areas of historic occurrence of primate-to-man transmissions of SIVs ancestral to HIVs: studies in these populations may provide crucial insights for treatment and prevention of HIV infection.

Recent findings suggest that Human Immunodeficiency Viruses, HIV-1 and 2, might have been transmitted to humans from particular primate species. It is thought that some Simian Immunodeficiency Viruses (SIVs), from which HIVs presumably originated, existed in their primate hosts for ages. Behavioral characteristics increasing the probability of contact between these primates and humans (such as keeping monkeys for pets, hunting monkeys for food, improper handling of the monkey meat, etc.) documented in some African countries could have facilitated cross-species transmissions (CSTs) of HIVs. As it has been shown, multiple CSTs took place for both HIVs (1 and 2) and then, in a globalizing world, these local events led to the pandemic. Here, it is brought forward that in the regions of epizooty of SIVs closely related to HIVs, some human populations might have had exposure history to these viruses dating back hundreds years. Lacking the important framework for further spread provided by nowadays globalization, these CSTs could have led to isolated local HIV outbreaks limited to particular tribes or groups. The infections could have extinguished some populations while on the other hand provided evolutionary pressure to select for mechanisms protective for HIV infection and/or disease. Thus, here it is hypothesized that in the areas of the habitat of primates infected with SIVs, from which HIVs are thought to be originated, there could be historically exposed populations which might possess biological correlates of protection from HIVs. Current knowledge on the distribution of primates hosting HIV-related SIVs suggests that epidemiological, primatological, anthropological and molecular biological studies in the areas of Cameroon, Gabon, both Congos and Equatorial Guinea (for HIV-1) and Guinea-Bissau, Senegal, Guinea, Ivory Cost, Sierra Leone and Liberia (for HIV-2) could lead to the discoveries of correlates of protection against HIVs. It is also hypothesized that virology studies in the same areas might reveal less virulent and/or infective viruses which could provide insights in the HIV pathogenesis and vaccinology.

Acquired Immunodeficiency Syndrome↗

HIV infection in families of HIV-positive and 'at-risk' HIV-negative women.

Research of HIV infection within the family has focused upon sexual partners and vertical transmission. The scope of the problem of multiple infections and clustering of HIV among family members has, thus far, been less extensively explored. The objectives of this study are to investigate HIV infection in family members of HIV-seropositive and HIV-seronegative high-risk women and to consider the impact of multiple HIV infections within the family. Baseline data were evaluated from a prospective observational cohort of 871 HIV-seropositive and 439 seronegative at-risk women who are participants in a longitudinal study of HIV in women at four sites in the USA (Montefiore, Bronx, NY; Johns Hopkins University, Baltimore, MD; Brown University, Providence, RI; Wayne State University, Detroit, MI). Women were asked if anyone close to them had HIV/AIDS or had died from HIV/AIDS. Responses which included HIV-positive family members were analyzed. In the seropositive cohort, 35% (307/871) of the women had a family member with HIV infection. Of these 307 women, 38% reported having a sibling, 24% a husband and 27% had more than one family member with HIV/AIDS. Forty-nine per cent of Latina women, 34% of black women, and 21% of white women reported having a family member with HIV/AIDS. Using logistic regression analysis, we found that Latina and black women were significantly more likely than white women to have a sibling, extended family member or more than one family member with HIV/AIDS. Compared to seropositive women, seronegative high-risk women enrolled in this study appear equally likely to have an HIV-infected family member. In this study of HIV-positive women and high-risk seronegative women, a third reported having multiple family members with HIV infection, most often in a sibling. The high prevalence of HIV within families, particularly in the families of Latina and black women, mandates attention in planning both prevention and care.

Black or African American↗

Sexual behaviour, condom use, and disclosure of HIV status in HIV infected heterosexual individuals attending an inner London HIV clinic.

BACKGROUND: The National Strategy for Sexual Health and HIV for England (2001) emphasised the role of HIV services in reducing secondary transmission of HIV through prevention work with HIV infected people. OBJECTIVE: To determine the sexual behaviour, condom use, and disclosure of HIV status of HIV infected heterosexuals attending an inner London HIV clinic. DESIGN: Cross sectional questionnaire study of heterosexual HIV infected individuals attending an HIV outpatient clinic. METHODS: We collected demographic data for all respondents and sexual behaviour data for those sexually active over the past year using a self administered questionnaire. Viral load and CD4 count for responders and age, sex, ethnicity, viral load, and CD4 count for non-responders were obtained from the clinic database. RESULTS: The response rate was 47.3% (n = 142). 100 participants reported being sexually active in the past year, of whom 73% used condoms when they last had vaginal sex. Knowledge of partner's HIV status was the only variable significantly associated with the participant disclosing their HIV status to their partner (p<0.001). In those who had disclosed their status, only knowledge of partner's HIV status was significantly associated with condom use (p = 0.03). CONCLUSIONS: Issues relating to non-disclosure and partner notification in HIV infected heterosexuals will need to be better understood to improve sexual health in this group and to reduce onward transmission of HIV.

Adolescent↗

Voluntary confidential HIV testing of STD patients in Switzerland, 1990-5: HIV test refusers cause different biases on HIV prevalences in heterosexuals and homo/bisexuals. Swiss Network of Dermatovenereology Policlinics.

OBJECTIVES: To monitor the prevalence of HIV infection among heterosexual and male homo/bisexual STD patients and assess the effect of HIV test refusers on the HIV prevalences. METHODS: A voluntary confidential HIV test was offered to all people diagnosed with an STD at the Swiss Network of Dermatovenerology Policlinics (SNDP) between July 1990 and June 1995. Anonymous sociodemographic and behavioural information was collected for each patient regardless of whether s/he accepted or refused the HIV test. RESULTS: The prevalence of HIV was 1.6% among heterosexuals and 22.4% homo/bisexual men and remained stable between July 1990 and June 1995. Refusal rates were 17.5% among heterosexuals and 16.0% among homo/bisexual men and did not change significantly over time. To assess the potential effect of HIV test refusers on the monitored HIV prevalences, we analysed test refusers by multivariate logistic regression. Among heterosexuals, refusal rates were significantly higher among patients with relatively low risk behaviours (patients reporting 0-1 sexual partners in the previous 6 months) while among homo/bisexual men they were significantly higher in those with high risk behaviours (patients reporting 10 or more sexual partners in the previous 6 months). CONCLUSIONS: We found high and stable HIV prevalences among patients treated for an STD at the SNDP. It appears that HIV test refusers biased HIV prevalences among heterosexuals and homo/bisexual men in different directions: in heterosexuals HIV prevalences were overestimated and in homo/bisexuals they were underestimated. A regular analysis of the characteristics of HIV test refusers should be an integral part of surveillance systems which use voluntary confidential HIV testing.

Bias↗

Tuberculin and anergy testing in HIV-seropositive and HIV-seronegative persons. Pulmonary Complications of HIV Infection Study Group.

OBJECTIVE: To determine the prevalence and predictors of reactivity to tuberculin purified protein derivative (PPD) and skin test anergy in patients with human immunodeficiency virus (HIV) infection and in HIV-seronegative controls. DESIGN: Cross-sectional analysis of baseline data from a prospective, multicenter study of pulmonary complications of HIV infection. SETTING: Community-based cohort of persons with and without HIV infection. PATIENTS: A total of 1171 HIV-seropositive patients without AIDS (841 homosexual men, 274 intravenous drug users, and 56 women with heterosexually acquired infection); 182 HIV-seronegative persons (125 homosexual men and 57 intravenous drug users). MEASUREMENTS: Delayed-type hypersensitivity response to tuberculin PPD, trichophytin, mumps, and Candida antigens; T-lymphocyte subsets. RESULTS: The prevalence of tuberculin PPD reactivity was higher among intravenous drug users than among homosexual men, in both HIV-seronegative (19.1% compared with 6.8%, P = 0.03) and HIV-seropositive persons (15.1% compared with 2.5%, P < 0.001). Among HIV-infected patients, the prevalence of tuberculin reactivity varied directly and that of anergy inversely with the absolute CD4 lymphocyte count. Prevalences were 1% and 72%, respectively, in patients with fewer than 200 CD4 cells/mm3, and 8.4% and 25.5%, respectively, in those with 600 CD4 cells/mm3 (P < 0.001 for both comparisons). Patients with HIV infection and fewer than 400 CD4 lymphocytes/mm3 had a lower prevalence of PPD reactivity than HIV-seronegative controls (2.7% compared with 10.0%, P < 0.001). The strongest predictors of tuberculin reactivity were intravenous drug use, black race, a previous positive PPD test result, and a history of Calmette-Guérin bacillus vaccination. The strongest predictor of anergy was HIV seropositivity. CONCLUSIONS: The response to delayed-type hypersensitivity antigens depends on immune status. The value of PPD and anergy testing in HIV-seropositive patients depends on the ability of such testing to predict subsequent tuberculosis, which is imprecisely known. Until more data or better methods are available, these tests should be done as early as possible in the course of HIV infection.

Adolescent↗

Pregnancy and HIV-1 incidence in 178 married couples with discordant HIV-1 serostatus: additional experience at an HIV-1 counselling centre in the Democratic Republic of the Congo.

To determine the effect of an HIV-1 counselling programme on rates of HIV-1 infection and pregnancy in a large group of married couples in Kinshasa, DRC with discordant HIV-1 infection status, we conducted a baseline cross-sectional HIV-1 seroprevalence study in two large Kinshasa businesses. We identified 178 married couples (mean duration of marriage = 12.3 years) with discordant HIV-1 serostatus (92 M+F-/86 M-F+). Seroincidence and pregnancy rates were observed during 310 person-years of follow-up (PYFU). The 92 M+F- couples had an HIV-1 incidence of 3.7/100 PYFU and a pregnancy rate of 8.6/100. The 86 M-F+ couples had a pregnancy rate of 6.8/100 PYFU and an HIV-1 incidence of 6.8/100 PYFU. Couples seeking to have children but minimize their HIV-1 transmission risk frequently had unprotected sex only during the woman's perceived monthly fertility period. This strategy resulted in the birth of 24 live-born children and only one (4%; 95% CL = 0.0-21.6%) new HIV infection in couples having a child. Only 1 of 6 women who developed HIV-1 infection (16. 7%; 95 C.L. = 0-40.4%) became pregnant. While seronegative men had more extramarital sex once their wives' positive HIV-1 infection status became known, most of these episodes involved safe sex. Divorce was rare. This study provides additional information concerning issues of safe sex in married couples with discordant HIV-1 infection status, the dynamics of HIV transmission within couples and the effect of serostatus notification on the marriage and on intramarital and extramarital sexual behaviour in Kinshasa, Congo.

Adult↗

Exon2 of HIV-2 Tat contributes to transactivation of the HIV-2 LTR by increasing binding affinity to HIV-2 TAR RNA.

Human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) express related Tat proteins that are encoded in two exons. Tat proteins bind directly to the TAR RNA element contained in the 5' ends of viral transcripts and thereby stimulate transcription through an as yet unidentified mechanism. We have investigated the functional significance of exon2 of the HIV-2 Tat protein by examining properties of proteins consisting of exon1 alone or exon1 + 2. In transactivation assays in vivo, exon2 modestly increased HIV-2 Tat stimulation of transcription from the HIV-2 long terminal repeat (LTR) but had no effect on transcription from the HIV-1 LTR. In HeLa cells, exon2 increased transactivation of the HIV-2 LTR by approximately three-fold, while in COS and Jurkat cells this value was less than two-fold. In binding assays in vitro, exon2 increased the binding affinity of the HIV-2 Tat protein to HIV-2 TAR RNA. Results with GAL4 fusion proteins and a synthetic promoter containing GAL4 DNA binding sites indicated that exon2 does not contribute to the HIV-2 Tat activation domain. These observations suggest that exon2 of HIV-2 Tat contributes to transactivation of the HIV-2 LTR by increasing the binding affinity to HIV-2 TAR RNA.

Binding Sites↗

Enhanced HIV-1 specific immune response by CpG ODN and HIV-1 immunogen-pulsed dendritic cells confers protection in the Trimera murine model of HIV-1 infection.

We have recently developed a novel small animal model for HIV-1 infection (Ayash-Rashkovsky et al., http://www.fasebj.org/cgi/doi/10.1096/fj.04-3184fje; doi:10.1096/fj.04-3184fje). The mice were successfully infected with HIV-1 for 4-6 wk with different clades of either T- or M-tropic isolates. HIV-1 infection was accompanied by rapid loss of human CD4+ T cells, decrease in CD4/CD8 ratio, and increased T cell activation. HIV specific human humoral and cellular immune responses were observed in all HIV-1 infected animals. In the present study, HIV specific human immune responses, both humoral and cellular, were generated in noninfected Trimera mice, after their immunization with gp120-depleted HIV-1 antigen, presented by autologous human dendritic cells. Addition of CpG ODN to the antigen-pulsed DCs significantly enhanced (by 2- to 30-fold) the humoral and cellular HIV-1 specific immune responses. Only mice immunized with the HIV-1 immunogen and CpG were completely protected from infection with HIV-1 after challenge with high infection titers of the virus. This novel small animal model for HIV-1 infection may thus serve as an attractive platform for rapid testing of candidate HIV-1 vaccines and of adjuvants and may shorten the time needed for the development and final assessment of protective HIV-1 vaccines in human trials.

AIDS Vaccines↗

Prevalence, incidence, and persistence or recurrence of trichomoniasis among human immunodeficiency virus (HIV)-positive women and among HIV-negative women at high risk for HIV infection.

Trichomoniasis has been implicated in the acquisition and transmission of human immunodeficiency virus (HIV) infection. The prevalence, incidence, and persistence or recurrence of trichomoniasis were assessed among HIV-positive women and among HIV-negative women at high risk for HIV infection. A total of 871 HIV-seropositive women and 439 HIV-seronegative women enrolled in the HIV Epidemiology Study (HERS) were seen biannually. The prevalence of trichomoniasis was 9.4%-29.5% among HIV-seropositive women and 8.2%-23.4% among HIV-seronegative women. Prevalence decreased over time, did not vary according to HIV status or CD4 cell count, and was higher among women who reported crack use (P=.02) or cigarette use (P=.02), women who had bacterial vaginosis (P=.02), and those who were black (compared with white women, P<.001). There were no differences, according to HIV status or CD4 cell count, in the adjusted incidence, unadjusted incidence, or persistence or recurrence of trichomoniasis. HIV infection does not make a woman more likely to have prevalent, incident, or persistent or recurrent trichomoniasis.

Female↗