Human immunodeficiency virus type 1 stimulatory activity by Gardnerella vaginalis: relationship to biotypes and other pathogenic characteristics.

Stimulation of human immunodeficiency virus (HIV) type 1 expression by Gardnerella vaginalis is one possible cause for an increase in the amount of virus in the genital tract. The ability of G. vaginalis to induce HIV expression in chronically infected U1 cells was investigated, along with its possible relationship to biotype, genotype, and resistance to metronidazole and bacteriocin. Significant HIV stimulatory activity was found in 5 (50%) lysates of G. vaginalis. The ability to induce HIV expression in U1 cells was statistically associated with G. vaginalis biotype (P=.048) but not with genotype or resistance to metronidazole and bacteriocin. Further studies to explore the in vivo relevance of HIV activation by G. vaginalis in the female genital tract are warranted, since prevention strategies of bacterial vaginosis and colonization by certain biotypes of G. vaginalis may be valuable in reducing the risk of sexual transmission of HIV.

Myeloid-related protein (MRP)-8 from cervico-vaginal secretions activates HIV replication.

OBJECTIVES: To identify a substance found in female genital tract secretions that enhances HIV expression in infected cells. DESIGN: Cervico-vaginal lavages (CVL), collected in sterile normal saline, were fractionated and tested for HIV-inducing activity using HIV-infected monocytes. METHODS: To purify the component(s) of CVL that enhance HIV production, Mono-Q ion exchange chromatography followed by Superose-12 molecular sieve analysis, and SDS--PAGE were performed. The purified protein was identified by amino acid sequence analysis. RESULTS: SDS--PAGE of bioactive fractions showed a 14 kDa polypeptide band. Amino acid sequence analysis of selected peptides from the 14 kDa band showed 100% homology with the myeloid-related protein (MRP)-8, an inflammatory protein found in mucosal secretions. Western blot analysis revealed that bioactive CVL contained more immunoreactive MRP-8 than samples without bioactivity. The HIV-inducing activity of MRP-8 was further confirmed by showing that human recombinant MRP-8 increased HIV expression by up to 40-fold. CONCLUSIONS: MRP-8 in cervico-vaginal secretions stimulates HIV production. Strategies aimed at blocking MRP-8 activity in the genital tract could reduce risk of sexual as well as maternal--infant transmission of HIV.

Induction of human immunodeficiency virus type 1 expression by anaerobes associated with bacterial vaginosis.

Bacterial vaginosis (BV) is a common disorder characterized by increased levels of anaerobic bacteria in the genital tract. BV has been associated with an increased rate of sexual transmission of human immunodeficiency virus (HIV). The effects of BV-associated anaerobic bacteria on HIV expression in monocytoid cells and T cells were examined. Peptostreptococcus asaccharolyticus and Prevotella bivia stimulated HIV expression in monocytoid cells, whereas Bacteroides ureolyticus, Peptostreptococcus anaerobius, and Lactobacillus acidophilus did not enhance HIV expression. P. asaccharolyticus also enhanced HIV expression in T cells and activated HIV long-terminal-repeat transcription in U38 cells. This report suggests a mechanism by which disturbances in vaginal flora could lead to a higher rate of sexual transmission of HIV. Furthermore, this study supports the idea that treatment of BV might serve as a preventive measure to reduce the risk of HIV transmission.

Detection and molecular mass determination of an HIV replication-enhancing female genital tract factor using a blot bioassay.

We previously reported that cervicovaginal lavages (CVL) contain a factor that enhances the replication of human immunodeficiency virus (HIV) by increasing virus transcription in T cells and monocytoid cells. This factor was named the HIV-inducing factor (HIF). To determine the molecular mass of HIF, we adapted a blot technique that involves nonreducing SDS-PAGE of CVL samples and electrophoretic transfer onto nitrocellulose paper followed by incubation of paper slices with HIV-infected monocytoid U1 cells. The slices with HIF bioactivity were detected by increased HIV production and measured by an HIV core protein (p24) ELISA. We refer to this technique as the "BioBlot" assay. The BioBlot assay successfully detected bioactivity of HIF anchored onto nitrocellulose and determined that HIF has a molecular mass of about 14 kDa. Paper slices with HIF-negative CVL samples as well as nitrocellulose paper samples without CVL did not enhance HIV production. This finding suggested that SDS-PAGE and nitrocellulose binding do not functionally alter the bioactive domain(s) of HIF structure. In addition to the detection of HIF bioactivity anchored to nitrocellulose and HIF molecular mass determination, the BioBlot technique offers an alternative, rapid method for other applications. These include the study of receptor-ligand interactions of mucosal proteins, direct bioactivity testing and molecular mass determination of secretory substances.

Association of indicators of bacterial vaginosis with a female genital tract factor that induces expression of HIV-1.

OBJECTIVE: The aim of this study was to determine the relationship of bacterial vaginosis and bacterial vaginosis-associated microorganisms with an HIV-inducing factor (HIF) found in cervicovaginal lavage. DESIGN: A total of 26 cervicovaginal lavage specimens collected from 17 women were used in this study to determine if HIF was significantly associated with features consistent with bacterial vaginosis. METHODS: Patients were evaluated for various clinical features including age, HIV status and stage, CD4 cell counts, clinical diagnosis of gynecological infections, vaginal pH, Gram stains of vaginal fluid, phase of menstruation, and presence of cervical dysplasia. Cervicovaginal lavage specimens were analyzed for the presence of HIF by U1 bioassay. The presence of Gardnerella vaginalis, and general Mycoplasmataceae, and specifically Mycoplasma hominis, Ureaplasma urealyticum, M. fermentans, M. genitalium in cervicovaginal lavage were determined by semiquantitative PCR. RESULTS: Eleven cervicovaginal lavage samples from seven women were HIF-positive and 15 cervicovaginal lavage samples from 11 women were HIF-negative (patient No. 8 had two HIF-negative cervicovaginal lavage and one HIF-positive cervicovaginal lavage). The following parameters were significantly associated with HIF: abnormal vaginal fluid pH (>4.5) (P = 0.006), Gram stains indicative of bacterial vaginosis (P = 0.007), normal menstrual cycle (P = 0.0007) and PCR detection and relative quantity of M. hominis (P = 0.0003, P = 0.002). CONCLUSIONS: This study indicates that HIF is closely associated with features of bacterial vaginosis.

Bacterial vaginosis-associated microflora isolated from the female genital tract activates HIV-1 expression.

Alteration of cervicovaginal microbial flora can lead to vaginosis, which is associated with an increased risk of HIV-1 transmission. We recently characterized a soluble HIV-inducing factor (HIF) from the cervicovaginal lavage (CVL) samples of women. The goals of this study were to determine the effect of cervicovaginal microflora on HIV-1 expression and to elucidate the relationship between HIF activity and microflora. Physiologically relevant microorganisms, Mycoplasma, diphtheroid-like bacteria, Gardnerella vaginalis, Streptococcus agalactiae, and Streptococcus constellatus, cultured from the CVL of a representative woman with a clinical condition of bacterial vaginosis and possessing HIF activity, induced HIV-1 expression. The magnitude of virus induction varied widely with the greatest stimulation induced by diphtheroid-like bacteria and Mycoplasma. The transcriptional induction by Mycoplasma was mediated by activation of the KB enhancer, an activation mechanism shared with HIF. Also as with HIF, Mycoplasma induced AP-1 dependent transcription. Polymerase chain reaction (PCR)-based speciation showed that the isolate was M. hominis. Our data indicate that bacterial vaginosis-associated microflora can enhance HIV-1 transcription and replication and identify M. hominis as a potential source for HIF activity. The virus-enhancing activities associated with the microflora and HIF may increase genital tract viral load, potentially contributing to HIV transmission.

Activation of human immunodeficiency virus type 1 expression by Gardnerella vaginalis.

Bacterial vaginosis (BV) is associated with an increased rate of sexual transmission of human immunodeficiency virus (HIV) type 1, and Gardnerella vaginalis is frequently isolated from the genital tracts of women with BV. G. vaginalis lysates were found to significantly stimulate HIV expression in monocytoid cells. Stimulation was significantly higher when lysates were heated at 100 degrees C for 5 min but was reduced by treatment with lysozyme or protease. G. vaginalis lysates also activated HIV expression in certain T cell lines. G. vaginalis lysates activated HIV long-terminal repeat transcription in HIV-infected cells and increased NF-kappaB binding activity, indicating an effect by G. vaginalis on HIV transcription. The activation of HIV production by G. vaginalis suggests that genital tract infection with G. vaginalis increases the risk of HIV transmission by increasing HIV expression in the genital tract. This may explain, at least in part, the increased rate of HIV transmission in women with BV.

Human immunodeficiency virus induction of corticotropin in lymphoid cells.

Disruption of the linkage among the immune, nervous, and endocrine systems may contribute to the pathology and symptoms of acquired immunodeficiency syndrome (AIDS). We investigated the role of human immunodeficiency virus (HIV) in altering these linkages via induction of corticotropin (ACTH) by lymphocytes. Cultured T lymphocytes (H9 cell line) were infected with HIV-1, after which ACTH production was measured and characterized at various time intervals by immunofluorescence and Western blotting. We report a coordinate expression of ACTH and p24 HIV core protein in H9 cells. Also, the kinetics of HIV-induced ACTH production by H9 T lymphoma cells are demonstrated using three different strains of HIV as well as UV-inactivated HIV. ACTH production corresponded with the appearance of p24 antigen and was maximal 35 days after infection. UV-inactivated HIV and the viral envelope protein, gp120, were also able to induce ACTH production in these cells, indicating that viral replication was not required for the ACTH induction. The HIV-induced ACTH was synthesized de novo and had the size and biological activity of pituitary ACTH. Inhibition of ACTH in HIV-infected lymphocyte cultures by anti-ACTH antiserum enhanced viral p24 expression. The significance of lymphocyte ACTH in AIDS is not clear, but these results suggest that it may restrict HIV replication and possibly infection.

A human immunodeficiency virus (HIV)-inducing factor from the female genital tract activates HIV-1 gene expression through the kappaB enhancer.

Virus-enhancing factors present in the female genital tract may influence the transmission of human immunodeficiency virus type 1 (HIV-1). Previously, the presence of a heat-stable soluble factor in the cervicovaginal lavage (CVL) fluid of both HIV-infected and -uninfected women that induces HIV-1 expression in T cells and monocytes was reported. Now this CVL factor was shown to increase HIV-1 gene expression through the activation of the kappaB enhancer in the viral long terminal repeat (LTR). DNA binding studies, together with functional studies using mutant LTR reporter constructs, indicate the requirement for an NF-kappaB-dependent pathway in the CVL-mediated activation of HIV-1 expression. CVL samples that activated HIV-1 expression also stimulated AP-1-dependent transcription. These data demonstrate that an HIV-inducing factor, distinct from heat-labile cytokines, present in the female genital mucosa can activate AP-1 and NF-kappaB and increase HIV-1 gene expression through the kappaB enhancer, possibly contributing to HIV-1 transmission.

Discrepancies between results by E-test and standard microbroth dilution testing of Streptococcus pneumoniae for susceptibility to vancomycin.

Vancomycin susceptibility testing of Streptococcus pneumoniae by the E-test consistently resulted in MICs that were at the upper limit of the 1-microgram/ml susceptible category defined by current National Committee for Clinical Laboratory Standards guidelines and were always higher than MICs obtained by microbroth dilution. Three of five E-test results for S. pneumoniae ATCC 49619 were higher than the acceptable limits.