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

Diversity of the HIV-1 long terminal repeat following mother-to-child transmission

A study of the human immunodeficiency virus Type 1 (HIV-1) 5' long terminal repeat (LTR) was performed to determine the extent of variation found within the LTR from 19 mother-infant pairs in Tanzania and to assess whether the LTR is useful in distinguishing maternal sequences that were transmitted to infants. HIV-1 subtypes A, C, and D as well as intersubtype recombinant LTR sequences were detected in mothers and infants. The LTR subtype was 100% concordant between mothers and their infants. Diversity calculations showed a significant reduction in LTR variation in infants compared to their mothers. However, the overall magnitude of LTR variation was less than that found in the env gene from the same individuals. These data suggest a selective constraint active upon the 5' long terminal repeat that is distinct from immune selective pressure(s) directed against HIV-1 structural genes. Detection of maternal LTR variants that were transmitted to infants may yield important information concerning nonstructural determinants of HIV-1 transmission from mother to infant.

Identification of a human lactoferrin-binding protein in Gardnerella vaginalis

Previous studies have shown that Gardnerella vaginalis can utilize iron-loaded human lactoferrin as a sole source of iron. In this study, G. vaginalis cells were shown to bind digoxigenin (DIG)-labeled human lactoferrin in a dot blot assay. Using the DIG-labeled human lactoferrin, a 120-kDa human lactoferrin-binding protein was detected by Western blot analysis of G. vaginalis proteins. The lactoferrin-binding activity of this protein was found to be heat stable. Competition studies indicated that this binding activity was specific for human lactoferrin. Treatment of G. vaginalis cells with proteases suggested that this protein was surface exposed. An increase in lactoferrin binding by the 120-kDa protein was observed in G. vaginalis cells grown under iron-restrictive conditions, suggesting that this activity may be iron regulated.

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.