Protein expression profiling of normal and neoplastic canine prostate and bladder tissue.

Prostatic carcinoma is an important cancer in both men and dogs. Dogs have been a valuable animal model for investigating prostate cancer, but their relevance is unclear as the origin of canine prostatic carcinomas is unknown. We hypothesized that a proteomic approach for diagnosis of these neoplasms might provide quantitative data useful for more complete characterization of their origin. Protein expression profiles were prepared from normal canine prostate glands and bladders. The normal protein profiles were then compared with protein expression profiles of three canine prostatic carcinomas. Two-dimensional differential in-gel electrophoresis (2-D DIGE) was used to analyse an average of approximately 1000 proteins per carcinoma. When compared with normal prostate tissue, the carcinomas exhibited greater than 2.5-fold difference in expression for an average of 230 proteins. Similar proteomic comparisons between the carcinomas and the normal bladder revealed a greater than 2.5-fold difference in expression for an average of 208 proteins. Mass spectrometry and protein database homology were used to identify nine proteins (alpha-enolase, vimentin, GRP78, endoplasmin (GRP94), albumin, keratins 7 and 8, haptoglobin, and transferrin) overexpressed by the carcinomas. Statistical testing demonstrated that keratin 7, GRP78, and endoplasmin were significantly overexpressed in the carcinomas compared with normal prostate or bladder. Principal components analysis revealed that the carcinomas formed a unique cluster distinct from either the normal prostate or normal bladder. In conclusion, proteomic analysis revealed that whereas the majority of proteins expressed by canine prostatic carcinomas are also expressed by normal and neoplastic bladder and prostate tissue, the carcinomas contained unique protein components that allowed their segregation as a distinct group separate from normal canine prostate and bladder. Additionally, several proteins uniquely expressed by canine prostatic carcinomas were also identified.

Transcriptional activation by estrogen receptor (ERalpha) and steroid receptor coactivator (SRC1) involves distinct mechanisms in yeast and mammalian cells.

Steroid receptors activate transcription in yeast cells via interactions with endogenous coactivators and/or basal factors. We examined the effects of mutations in the ligand binding domain on the transcriptional activity of ERalpha in yeast. Our results show that mutations in Helix 3 (K366A) and Helix 12 (M547A, L548A) disrupt transcriptional activity of ERalpha in yeast, as previously observed in mammalian cells. However, replacement of a conserved tyrosine residue in Helix 12 with alanine or aspartate (Y541A and Y541D), which renders ERalpha constitutively active in mammalian cells, had only a weak stimulatory effect on ligand-independent reporter activation by ERalpha in yeast. Two-hybrid interaction experiments revealed that a Y541A mutant expressed in yeast was capable of ligand-independent binding to a mammalian coactivator, suggesting that there is a subtle difference in how this mutant interacts with mammalian and yeast cofactors. We also show that the ligand-dependent activities of ERalpha and progesterone receptor (PR) in yeast cells were strongly enhanced by the human p160 protein steroid receptor coactivator (SRC1), but not by CREB-Binding Protein (CBP) or the p300/CBP associated factor (P/CAF). Although the SRC1 activation domains AD1 and AD2 are functional in yeast, deletion of these sequences only partially impaired SRC1 coactivator function in this organism; this is in contrast to similar experiments in mammalian cells. Thus SRC1 sequences involved in recruitment of CBP/p300 and Co-Activator-Associated Arginine Methyltransferase (CARM-1) in mammalian cells are not essential for its function in yeast, suggesting that SRC1 operates via distinct mechanisms in yeast and mammalian cells.

Immunogenicity of a recombinant human immunodeficiency virus (HIV)-canarypox vaccine in HIV-seronegative Ugandan volunteers: results of the HIV Network for Prevention Trials 007 Vaccine Study.

In the first preventative human immunodeficiency virus (HIV) vaccine study to be carried out in Africa, 40 HIV-seronegative Ugandan volunteers were randomly assigned to receive a canarypox vector containing HIV-1 clade B (env and gag-pro) antigens (ALVAC-HIV; n = 20), control vector containing the rabies virus glycoprotein G gene (n = 10), or saline placebo (n = 10). Cytotoxic T lymphocyte activity against target cells expressing clade A, B, and D antigens was assessed using standard chromium-release and confirmatory interferon-gamma enzyme-linked immunospot (ELISPOT) assays. Neutralizing antibody responses to cell line-adapted strains and primary isolates in all 3 clades were also tested. Twenty percent of vaccine recipients generated detectable cytolytic responses to either Gag or Env, and 45% had vaccine-induced HIV-specific CD8(+) T cell responses, as measured by the ELISPOT assay. In contrast, only 5% of the control group had vaccine-specific responses. Neutralizing antibodies against primary and laboratory-adapted HIV-1 clade B strains were seen in 10% and 15% of vaccine recipients, respectively, but responses against clades A and D were not detected. Although the immunogenicity of this clade B-based vaccine was low, ALVAC-HIV elicited CD8(+) T cell responses with detectable cross-activity against clade A and D antigens in a significant proportion of vaccine recipients.

Effects of CCR5-Delta32, CCR2-64I, and SDF-1 3'A alleles on HIV-1 disease progression: An international meta-analysis of individual-patient data.

BACKGROUND: Studies relating certain chemokine and chemokine receptor gene alleles with the outcome of HIV-1 infection have yielded inconsistent results. OBJECTIVE: To examine postulated associations of genetic alleles with HIV-1 disease progression. DESIGN: Meta-analysis of individual-patient data. SETTING: 19 prospective cohort studies and case-control studies from the United States, Europe, and Australia. PATIENTS: Patients with HIV-1 infection who were of European or African descent. MEASUREMENTS: Time to AIDS, death, and death after AIDS and HIV-1 RNA level at study entry or soon after seroconversion. Data were combined with fixed-effects and random-effects models. RESULTS: Both the CCR5-Delta32 and CCR2-64I alleles were associated with a decreased risk for progression to AIDS (relative hazard among seroconverters, 0.74 and 0.76, respectively; P = 0.01 for both), a decreased risk for death (relative hazard among seroconverters, 0.64 and 0.74; P < 0.05 for both), and lower HIV-1 RNA levels after seroconversion (difference, -0.18 log(10) copies/mL and -0.14 log(10) copies/mL; P < 0.05 for both). Having the CCR5-Delta32 or CCR2-64I allele had no clear protective effect on the risk for death after development of AIDS. The results were consistent between seroconverters and seroprevalent patients. In contrast, SDF-1 3'A homozygotes showed no decreased risk for AIDS (relative hazard for seroconverters and seroprevalent patients, 0.99 and 1.03, respectively), death (relative hazard, 0.97 and 1.00), or death after development of AIDS (relative hazard, 0.81 and 0.97; P > 0.5 for all). CONCLUSIONS: The CCR5-Delta32 and CCR2-64I alleles had a strong protective effect on progression of HIV-1 infection, but SDF-1 3'A homozygosity carried no such protection.

Vaccine-induced antibodies to the native, oligomeric envelope glycoproteins of primary HIV-1 isolates.

A simple and sensitive method for measuring antibodies to primary human immunodeficiency virus type 1 (HIV-1) isolates has been developed. The flow cytometric immuno-fluorescence assay detects antibodies that bind to the native, oligomeric form of the envelope glycoprotein (gp120) expressed on the surface of PM-1 cells infected with primary isolates of HIV-1. Sera from people infected with HIV-1 or those immunized with recombinant gp120 vaccines were tested. Significant correlation was observed between neutralizing activity and oligomeric gp120 binding activity. Thirteen to 100% of individuals immunized with the subtype B bivalent vaccine AIDSVAX B/B developed oligomeric gp120 binding antibodies against a variety of subtype B primary isolates. For several isolates, AIDSVAX B/B sera reacted better than monovalent AIDSVAX B sera, suggesting that addition of the second immunogen improved the breadth of the antibody response. Cross-subtype binding activities, induced by AIDSVAX B/B, were lower than activities to subtype B isolates, suggesting that additional immunogen(s) may be desirable in vaccine(s) formulated for geographic regions where non-B subtypes are dominant.

Homozygous and heterozygous CCR5-Delta32 genotypes are associated with resistance to HIV infection.

OBJECTIVE: To investigate evidence for resistance to HIV-1 infection associated with the heterozygous genotype CCR5-+/Delta32 and with the homozygous genotype CCR5-Delta32/Delta32, which results in a nonfunctional CCR5 receptor. DESIGN: Cohort study of initially HIV-seronegative high-risk individuals from eight different cities. Enrollment data were analyzed to investigate the association of demographic factors and risk behaviors with CCR5 genotypes on the assumption that increased genotype prevalence among persons with histories of longer or more intensive exposure to HIV would indicate HIV resistance associated with that genotype. Longitudinal data were analyzed to investigate the association of HIV seroincidence with CCR5 genotypes. The cohort of 2996 individuals included 1892 men who have sex with men (MSM), 474 male injection drug users (IDUs), 347 women at heterosexual risk, and 283 female IDUs. MEASUREMENTS: CCR5 genotype, HIV serostatus, demographic factors, and risk behaviors during the 6 months before enrollment, followed by measurement of HIV seroincidence during the subsequent 18 months (for men) and 24 months (for women). RESULTS: Forty (1.3%) subjects were homozygous CCR5-Delta32/Delta32 and 387 (12.9%) were heterozygous CCR5-+/Delta32. All but 1 CCR5-Delta32/Delta32 individuals and 51 CCR5-+/Delta32 individuals were Caucasian. Among 1531 Caucasian MSM, CCR5-+/Delta32 individuals were present more frequently (22.3%) among those reporting unprotected receptive anal intercourse than among those not reporting this risk (15.9%) (p =.002), suggesting a selective advantage of the heterozygous genotype. CCR5-+/Delta32 individuals also had a significantly reduced relative risk of HIV seroconversion adjusted for unprotected receptive anal intercourse compared with CCR5-/+ individuals (relative risk = 0.30, 95% confidence interval [CI]: 0.08-0.97). CCR5-Delta32/Delta32 prevalence among Caucasian MSM was significantly associated with age among subjects recruited from high HIV seroprevalence cities (New York City and San Francisco) (odds ratio [OR] for each decade increase in age = 2.57, CI: 1.56-4.21) but not among those recruited from lower HIV prevalence sites (Boston, Chicago, Philadelphia, Seattle, and Providence/Pawtucket, Rhode Island) (OR = 1.20, CI: 0.75-1.89). CONCLUSIONS: Cross-sectional and longitudinal analyses indicated that among high-risk HIV seronegative MSM, CCR5-+/Delta32 and CCR5-Delta32/Delta32 are associated with protection against HIV infection. These findings imply that strategies aimed at reducing susceptibility to HIV infection by blocking CCR5 receptor sites need not seek blockage of all receptor sites to achieve an imperfect but substantial degree of protection.

p53 Stimulates TFIID-TFIIA-promoter complex assembly, and p53-T antigen complex inhibits TATA binding protein-TATA interaction.

Simian virus 40 large T antigen has been shown to inhibit p53-mediated transcription once tethered to p53-responsive promoters through interaction with p53. In this study we report that p53 stimulates transcription by enhancing the recruitment of the basal transcription factors, TFIIA and TFIID, on the promoter (the DA complex) and by inducing a conformational change in the DA complex. Significantly, we have demonstrated that T antigen inhibits p53-mediated transcription by blocking this ability of p53. We investigated the mechanism for this inhibition and found that DA complex formation was resistant to T-antigen repression when the TFIID-DNA complex was formed prior to addition of p53-T antigen complex, indicating that the T antigen, once tethered to the promoter by p53, targets TFIID. Further, we have shown that the p53-T antigen complex prevents the TATA binding protein from binding to the TATA box. Thus, these data suggest a detailed mechanism by which p53 activates transcription and by which T antigen inhibits p53-mediated transcription.

Safety and immunogenicity of a canarypox-vectored human immunodeficiency virus Type 1 vaccine with or without gp120: a phase 2 study in higher- and lower-risk volunteers.

Live attenuated viral vectors that express human immunodeficiency virus (HIV) antigens are being developed as potential vaccines to prevent HIV infection. The first phase 2 trial with a canarypox vector (vCP205, which expresses gp120, p55, and protease) was conducted in 435 volunteers with and without gp120 boosting, to expand the safety database and to compare the immunogenicity of the vector in volunteers who were at higher risk with that in volunteers at lower risk for HIV infection. Neutralizing antibodies to the MN strain were stimulated in 94% of volunteers given vCP205 plus gp120 and in 56% of volunteers given vCP205 alone. CD8(+) cytotoxic T lymphocyte cells developed at some time point in 33% of volunteers given vCP205, with or without gp120. Phase 3 field trials with these or similar vaccines are needed, to determine whether efficacy in preventing HIV infection or in slowing disease progression among vaccinees who become infected is associated with the level and types of immune responses that were induced by the vaccines in this study.

Comparison of techniques for HIV-1 RNA detection and quantitation in cervicovaginal secretions.

PRINCIPLES: HIV-1 in female genital secretions has been measured using swabs, Sno Strips (Akorn, Inc., Buffalo Grove, IL), and cervicovaginal lavage (CVL), but little is known regarding the comparability of these collection techniques. METHODS: We compared HIV-1 RNA detection and quantity in specimens obtained from HIV-1-seropositive women in Kenya using three sample collection techniques and three storage techniques and evaluated reproducibility in samples collected 5 days apart. Specimens were stored in no medium, freezing medium, or TRI Reagent (Molecular Research Center, Cincinnati, OH) for 2 to 15 months. RESULTS: HIV-1 RNA assays were conducted on 640 specimens from 20 antiretroviral naive women. Storage in TRI Reagent significantly enhanced detection of genital HIV-1 and yielded significantly higher mean log10 RNA levels than specimens collected in either no or freezing medium. The prevalence of HIV-1 RNA detection in TRI Reagent ranged from 50% to 80% depending on collection method and was highest in cervical swabs. Mean log10 HIV-1 RNA levels were 3.1 log10 copies/cervical swab, 2.6 log10 copies/cervical Sno Strip, 2.5 log10 copies/vaginal swab, 2.4 log10 copies/vaginal Sno Strip, 2.9 log10 copies/ml for cervicovaginal lavage (CVL) cell pellet, and 2.1 log10 copies/ml in CVL supernatant. Comparing specimens from days 1 and 6, there was significant concordance of HIV-1 RNA detection and correlation of HIV-1 RNA levels for cervical swabs, vaginal swabs, vaginal Sno Strips, and CVL cell pellets (kappa, 0.5-0.9; r, 0.5-0.9), but not for cervical Sno Strips or CVL supernatants. CONCLUSIONS: Cervical or vaginal swab, vaginal Sno Strip, and CVL collection led to reproducible measurement of genital HIV-1 RNA, despite storage for several months and international transport. Collection using swabs was simpler than Sno Strips or cervicovaginal lavage, and yielded the highest prevalence of HIV-1 RNA detection and reproducibility.

Early human immunodeficiency virus (HIV) infection in the HIV Network for Prevention Trials Vaccine Preparedness Cohort: risk behaviors, symptoms, and early plasma and genital tract virus load.

Risk behaviors, symptoms, and virologic characteristics were studied among 103 human immunodeficiency virus (HIV) seroconverters in vaccine preparedness cohorts during 1995-1998. Overall, 83% of subjects were men who had sex with men; most reported multiple risk episodes and symptoms (84%, > or =1 symptom) during seroconversion. Acute HIV was diagnosed in only 8 of 50 who sought medical care. Median initial pretreatment plasma virus load was 25,800 copies/mL (range, undetectable-262,000 copies/mL) a mean of 4 months after seroconversion, and 9.7% had nucleoside-associated mutations; none had multidrug resistance. Semen virus load was more variable, 1.3 log(10) lower and modestly correlated (r=.28; 95% confidence interval, 0.16-0.42) with plasma among untreated men. When the plasma RNA level was <5000 copies/mL, 32% of untreated men, 13% on nucleoside regimens, and 7% on protease inhibitor-containing regimens had detectable seminal RNA. Acute HIV was seldom diagnosed, representing missed opportunities for early treatment and prevention. Most subjects had several relatively stable virus loads before initiation of antiretrovirals, indicating feasibility of assessing HIV vaccines on virus set point in efficacy trials.

Analysis of the steroid receptor coactivator 1 (SRC1)-CREB binding protein interaction interface and its importance for the function of SRC1.

The transcriptional activity of nuclear receptors is mediated by coactivator proteins, including steroid receptor coactivator 1 (SRC1) and its homologues and the general coactivators CREB binding protein (CBP) and p300. SRC1 contains an activation domain (AD1) which functions via recruitment of CBP and and p300. In this study, we have used yeast two-hybrid and in vitro interaction-peptide inhibition experiments to map the AD1 domain of SRC1 to a 35-residue sequence potentially containing two alpha-helices. We also define a 72-amino-acid sequence in CBP necessary for SRC1 binding, designated the SRC1 interaction domain (SID). We show that in contrast to SRC1, direct binding of CBP to the estrogen receptor is weak, suggesting that SRC1 functions primarily as an adaptor to recruit CBP and p300. In support of this, we show that the ability of SRC1 to enhance ligand-dependent nuclear receptor activity in transiently transfected cells is dependent upon the integrity of the AD1 region. In contrast, the putative histone acetyltransferase domain, the Per-Arnt-Sim basic helix-loop-helix domain, the glutamine-rich domain, and AD2 can each be removed without loss of ligand-induced activity. Remarkably, a construct corresponding to residues 631 to 970, which contains only the LXXLL motifs and the AD1 region of SRC1, retained strong coactivator activity in our assays.

Core LXXLL motif sequences in CREB-binding protein, SRC1, and RIP140 define affinity and selectivity for steroid and retinoid receptors.

An alpha-helical motif containing the sequence LXXLL is required for the ligand-dependent binding of transcriptional co-activators to nuclear receptors. By using a peptide inhibition assay, we have defined the minimal "core" LXXLL motif as an 8-amino acid sequence spanning positions -2 to +6 relative to the primary conserved leucine residue. In yeast two-hybrid assays, core LXXLL motif sequences derived from steroid receptor co-activator (SRC1), the 140-kDa receptor interacting protein (RIP140), and CREB-binding protein (CBP) displayed differences in selectivity and affinity for nuclear receptor ligand binding domains. Although core LXXLL motifs from SRC1 and RIP140 mediated strong interactions with steroid and retinoid receptors, three LXXLL motifs present in the global co-activator CBP were found to have very weak affinity for these proteins. Core motifs with high affinity for steroid and retinoid receptors were generally found to contain a hydrophobic residue at position -1 relative to the first conserved leucine and a nonhydrophobic residue at position +2. Our results indicate that variant residues in LXXLL core motifs influence the affinity and selectivity of co-activators for nuclear receptors.

Home collection for frequent HIV testing: acceptability of oral fluids, dried blood spots and telephone results. HIV Early Detection Study Group.

OBJECTIVE: To assess the feasibility and acceptability of bimonthly home oral fluid (OF) and dried blood spot (DBS) collection for HIV testing among high-risk individuals. DESIGN: A total of 241 participants [including men who have sex with men (MSM), injecting drug users (IDU), and women at heterosexual risk] were recruited from a randomly selected subset of study participants enrolled at four sites in the HIV Network for Prevention Trials (HIVNET) cohort, and assigned at random to bimonthly home collection of OF or DBS specimens over a 6 month interval. Participants could select telephone calls or clinic visits to receive HIV test results. METHODS: Bimonthly specimens were tracked for adherence to the schedule, were evaluated for adequacy for testing, and tested using antibody assays and polymerase chain reaction (PCR) for DBS. The acceptability of bimonthly home OF and DBS collection and telephone counseling was assessed in an end-of-study questionnaire. RESULTS: The laboratory received 96 and 90% of expected OF and DBS specimens, respectively; 99% of each specimen type was adequate for testing. Almost all (95%) participants chose results disclosure by telephone. The majority of participants (85%) reported that bimonthly testing did not make them worry more about HIV, and almost all (98%) judged that with bimonthly testing their risk behavior remained the same (77%) or became less risky (21%). CONCLUSION: Bimonthly home specimen collection of both OF and DBS with telephone counseling is acceptable and feasible among study participants at high risk. These methods will be useful for the early detection of HIV infection and remote follow-up of research cohort participants in HIV vaccine and prevention trials.

Use of creatine and other supplements by members of civilian and military health clubs: a cross-sectional survey.

A survey was used to collect anonymous cross-sectional data on demographics, exercise habits, and use of creatine and other supplements by exercisers in civilian (C) and military (M) health clubs. M (n = 133) reported more aerobic training and less use of creatine and protein supplements than C (n = 96, p <.05). Supplement users (SU, n = 194) and nonusers (SNU, n = 35) engaged in similar frequency and duration of aerobic exercise, as well as number of resistance exercise repetitions, but SU completed more sets for each resistance exercise (x- +/- SE, 5 +/- 1) than SNU (3 +/- 1, p < or =.05). Significant (p < or =.05) associations were observed between SU and resistance training goal of strength (as opposed to endurance), as well as greater frequency of resistance training. Male gender, resistance training goal of strength, lower frequency and duration of aerobic training, and use of protein, b-hydroxy-b-methyl butyrate, and androstenedione/dehydroepiandrosterone supplements were all associated with creatine use (p <.05). For creatine users, the dose and length of creatine supplementation was 12.2 +/- 2.7 g.day-1 for 40 +/- 5 weeks. Popular magazines were the primary source of information on creatine (69%) compared to physicians (14%) or dietitians (10%, p < or =.0001). This study underscores two potential public health concerns: (a) reliance on popular media rather than allied-health professionals for information on creatine, and (b) use of creatine, a popular supplement with unknown long-term effects, in combination with other anabolic supplements of questionable efficacy and/or safety.

Transcription by RNA polymerase II in DNA-PK deficient scid mouse cells.

DNA-dependent protein kinase (DNA-PK) is involved in DNA repair but there is some evidence to suggest that it is also involved in regulating transcription. We used a pair of cell lines, SCVA2 and SC(8)-10, which are DNA-PK negative and positive respectively, in order to examine the effect of DNA-PK upon transcription. Initial experiments were performed using p53 as an activator of transcription because DNA-PK has been proposed as a candidate upstream activator of p53. It was found both in vivo and in vitro that efficient p53-dependent transcription required the presence of DNA-PK. However, phosphorylation of p53 by DNA-PK did not affect the DNA-binding ability of p53 nor its transcriptional activity when tested in vitro. Subsequent in vivo experiments suggested that a number of transcription activators functioned more efficiently in the presence of DNA-PK. Therefore DNA-PK may play a general role in regulation of transcription driven by RNA polymerase II. In addition, DNA-PK is shown to have no specific effect on p53-dependent transcription.

Identification of a high-risk heterosexual population for HIV prevention trials in Rio de Janeiro, Brazil. Projeto Praço Onze Study Group.

The study of interventions to prevent HIV transmission requires access to populations with a high rate of HIV transmission. We estimated HIV incidence among heterosexual males and females who were seen at an HIV testing site in Rio de Janeiro, Brazil. Stored sera from individuals who visited the site between March and December 1998 were analyzed using the sensitive/less sensitive (S/LS) assay and a chart abstraction was performed. During the study period, 6353 serum samples were tested. Of those tested, 1203 were found to be HIV-seropositive or indeterminate, of which 1050 (87%) remained available for further testing. In addition, 84 serum samples, representing 63 adults, were found to produce results suggesting early HIV infection. Of these, 14 were heterosexual and female (median age, 38 years), and 19 were heterosexual and male (median age, 25 years). The estimated HIV seroincidence was 1.9 (95% confidence limits (CL), 0.9%-3.9%) and 2.8 (95% CL, 1.4%-5.3%) per 100 person-years among heterosexual women and men, respectively. A survey on willingness to participate in future placebo-controlled HIV vaccine trials in this population indicated that 54.5% and 53.9% of heterosexual women and men, respectively, indicated that they would definitely be willing to participate. We have identified a heterosexual population in Rio de Janeiro with a high rate of HIV transmission willing to participate in placebo-controlled vaccine trials. This study demonstrates the usefulness of the newly described S/LS assay, which allows one to estimate HIV incidence from single serum specimens.

Shorter survival of SDF1-3'A/3'A homozygotes linked to CD4+ T cell decrease in advanced human immunodeficiency virus type 1 infection.

The SDF-1 3'A allelic polymorphism has been reported to influence either positively or negatively the progression of human immunodeficiency virus type 1 (HIV-1) disease. Therefore, the SDF-1 genotype of 729 HIV-1-infected individuals pooled from 3 distinct cohorts was determined. A statistically nonsignificant association between the SDF1-3'A/3'A genotype and accelerated disease progression was evident among seroconverters (n=319), but a striking correlation of decreased survival after either diagnosis of AIDS according to the 1993 definition or loss of CD4(+) T cell counts <200 was observed. The relative hazards for SDF1-3'A/3'A homozygotes, compared with heterozygotes and wild-type homozygotes were 2.16 (P=.0047), for time from diagnosis according to the 1993 Centers for Disease Control and Prevention AIDS case definition (AIDS-'93) to death, and 3.43 (P=.0001), for time from CD4(+) T cells <200 to death. Because no difference in survival was observed after diagnosis according to AIDS-'87, the association of the SDF1-3'A/3'A genotype with the accelerated progression of late-stage HIV-1 disease appears to be explained for the most part by the loss of CD4(+) T lymphocytes.

Dissociation of immunologic and virologic responses to highly active antiretroviral therapy.

OBJECTIVE: Immunologic markers, levels of HIV DNA, and infectious HIV were compared in partial responders (PR) to HAART who had high plasma HIV RNA levels but stable or increasing levels of CD4+ peripheral blood mononuclear cells (PBMC), and patients with complete failure (CF) who had very low or decreasing levels of CD4+ PBMC and high plasma HIV RNA levels. DESIGN AND METHODS: CD4 and CD8 levels were monitored by flow cytometry. Beta2-microglobulin (beta2M) and neopterin levels were measured by quantitative enzyme immunoassays. Plasma and PBMC from 11 PR and 13 CF were analyzed for infectious HIV levels in limiting dilution cultures. Polymerase chain reaction (PCR) assays were used to quantify cellular HIV DNA and plasma HIV RNA. RESULTS: In comparison with CF, PR had little or no CD4+ cell loss, a substantial increase in CD8+ cells, significantly fewer positive plasma HIV cultures (p = .03), lower frequencies of infectious HIV in total PBMC (p = .005) and in CD4+ PBMC (p < .001), and lower frequencies of HIV DNA in CD4+ PBMC (p = .007). CONCLUSIONS: Lower levels of infectious HIV and a lower frequency of CD4+ PBMC that contain "productive" HIV DNA in PR as compared with CF may contribute to the stable or increasing CD4+ PBMC levels of the PR. However, HAART may also have effects on lymphocyte homeostasis independent of its antiviral activity.