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1.  Longitudinal Assessment of Pigtailed Macaque Lower Genital Tract Microbiota by Pyrosequencing Reveals Dissimilarity to the Genital Microbiota of Healthy Humans 
AIDS Research and Human Retroviruses  2012;28(10):1244-1249.
Abstract
Vaginal bacterial communities play an important role in human health and have been shown to influence HIV infection. Pigtailed macaques (Macaca nemestrina) are used as an animal model of HIV vaginal infection of women. Since the bacterial microbiota could influence retrovirus infection of pigtailed macaques, the genital microbiota in 10 cycling macaques was determined by pyrosequencing. The microbiota of all macaques was polymicrobial with a median of 13 distinct genera. Strikingly, the genera Sneathia and Fusobacterium, both in the phylum Fusobacteria, accounted for 18.9% and 13.3% of sequences while the next most frequent were Prevotella (5.6%), Porphyromonas (4.1%), Atopobium (3.6%), and Parvimonas (2.6%). Sequences corresponding to Lactobacillus comprised only 2.2% of sequences on average and were essentially all L. amylovorus. Longitudinal sampling of the 10 macaques over an 8-week period, which spanned at least one full ovulatory cycle, showed a generally stable presence of the major types of bacteria with some exceptions. These studies show that the microbiota of the pigtailed macaques is substantially dissimilar to that found in most healthy humans, where the genital microbiota is usually dominated by Lactobacillus sp. The polymicrobial makeup of the macaque bacterial populations, the paucity of lactobacilli, and the specific types of bacteria present suggest that the pigtailed macaque microbiota could influence vaginal retrovirus infection.
doi:10.1089/aid.2011.0382
PMCID: PMC3448102  PMID: 22264029
2.  A Comparison of Lower Genital Tract Glycogen and Lactic Acid Levels in Women and Macaques: Implications for HIV and SIV Susceptibility 
Abstract
Understanding factors that affect heterosexual transmission of HIV in women is of great importance. Lactobacilli in the lower genital tract of women utilize glycogen in vaginal epithelial cells as an energy source and produce lactic acid. The resultant vaginal acidity is believed to provide protection against HIV infection. Conversely, bacterial vaginosis (BV) is characterized by less lactic acid and a higher pH, and is associated with increased susceptibility to HIV infection. Because vaginal infection of macaques with simian immunodeficiency virus (SIV) or simian-human immunodeficiency virus (SHIV) is used as a model to study HIV sexual transmission, and because previous studies have shown a paucity of lactobacilli in rhesus macaques' lower genital tract, we compared lactic acid and glycogen levels in the genital fluid of rhesus and pigtail macaques with levels found in humans. The levels of lactic acid were lower in both rhesus (median=1.2 mol lactate/mg protein) and pigtail macaques (median=0.7 mol/mg) compared to women with healthy genital microbiota (median=4.2 mol/mg). Glycogen levels were significantly lower in both rhesus (median=0.004 μg glycogen/μg protein) and pigtail macaques (median=0 μg/μg) than in women (median=0.2 μg/μg). No significant differences in glycogen or lactate levels were observed comparing longitudinally collected samples from cycling pigtail macaques. These data show that the previously reported scarcity of lactobacilli in macaques correlates with low glycogen and lactic acid levels. These findings have important implications for studies of vaginal infection of macaques with SIV or SHIV and further our understanding of how the bacterial microbiota influences HIV infection.
doi:10.1089/aid.2011.0071
PMCID: PMC3251838  PMID: 21595610
3.  Identification of Rhesus Macaque Genital Microbiota by 16S Pyrosequencing Shows Similarities to Human Bacterial Vaginosis: Implications for Use as an Animal Model for HIV Vaginal Infection 
Abstract
The composition of the lower genital tract microbiota in women is believed to affect the risk of sexually acquiring HIV. Since macaque genital microbiota could similarly impact vaginal infection with SIV we identified microbiota in 11 rhesus macaques using multitag pyrosequencing of the 16S rRNA gene. The microbiota was polymicrobial with a median of nine distinct bacterial taxa per macaque (range 3–16 taxa, each constituting 1% or more of the sequences). Taxa frequently found included Peptoniphilus, Sneathia, Porphyromonas, Mobiluncus, Atopobacter, Dialister, Thioreductor, Prevotella, and Streptococcus, many of which are also frequently found in women with bacterial vaginosis. Lactobacillus sequences (mostly L. johnsonii) were found in only four macaques but were not predominant in any (median of 0% of sequences, range 0–39%). All macaques were resampled 6 months after the first time point to determine the stability of the microbiota. The microbiota remained polymicrobial with a median of 10 taxa (range 6–18). Microbial patterns remained similar for six of the macaques, changed substantially in two, and had a mixed pattern in three. Significant sialidase enzyme activity, a marker of bacteria vaginosis in women, was detected in genital fluid from 9/11 and 8/11 macaques from the first and second time points, respectively. These results show that the macaque lower genital microbiota resembled a bacteria vaginosis-type microbiota in women and suggest that the microbiota of macaques in captivity promote rather than protect against vaginal infection with SIV. These results also suggest macaques could be used as an animal model to study some aspects of bacterial vaginosis.
doi:10.1089/aid.2009.0166
PMCID: PMC2835387  PMID: 20156101
4.  HSV-2 infection increases HIV DNA detection in vaginal tissue of mice expressing human CD4 and CCR5 
AIDS research and human retroviruses  2009;25(11):1157-1164.
The goal of this study was to develop an in vivo murine model that can be used to study the influence of HSV-2 on HIV infection. Mice expressing transgenes for human CD4, CCR5 and Cyclin T1 were infected intra-vaginally with HSV-2 and 3-7 days later infected with HIV. HIV DNA was detected by real time PCR. The frequency of detection of HIV DNA was significantly higher (65%) in vaginal tissue of HSV-2-infected mice compared to mock-infected mice (35%) when HIV was given 3 days after HSV-2. HSV-2 infected mice also had significantly higher levels of HIV DNA in vaginal tissue. HIV DNA was not detected in vaginal tissue of mice lacking human CD4. Longer periods (5 or 7 days) between infection with HSV-2 and HIV did not increase the frequency of detection or the amount of HIV DNA detected. HIV DNA was also detected in lymph nodes from some of the mice that were infected intra-vaginally with HSV-2 and HIV. Flow cytometric and mRNA analysis of human CD4 in vaginal tissue suggested that HSV-2 infection increased the number of T cells expressing human CD4 in vaginal tissue. This study provides evidence that HIV infection of cells occurs in the vagina of mice expressing human CD4, CCR5 and Cyclin T1 and that HSV-2 infection increases HIV infection. These findings demonstrate that this model can be used to study the mechanisms responsible for increased susceptibility to HIV in HSV-2-infected persons and for testing preventative treatments.
doi:10.1089/aid.2009.0035
PMCID: PMC2826840  PMID: 19886831
5.  HSV Type 2 Infection Increases HIV DNA Detection in Vaginal Tissue of Mice Expressing Human CD4 and CCR5 
AIDS Research and Human Retroviruses  2009;25(11):1157-1164.
Abstract
The goal of this study was to develop an in vivo murine model that can be used to study the influence of HSV-2 on HIV infection. Mice expressing transgenes for human CD4, CCR5, and Cyclin T1 were infected intravaginally with HSV-2 and 3–7 days later infected with HIV. HIV DNA was detected by real-time PCR. The frequency of detection of HIV DNA was significantly higher (65%) in vaginal tissue of HSV-2-infected mice compared to mock-infected mice (35%) when HIV was given 3 days after HSV-2. HSV-2-infected mice also had significantly higher levels of HIV DNA in vaginal tissue. HIV DNA was not detected in vaginal tissue of mice lacking human CD4. Longer periods (5 or 7 days) between infection with HSV-2 and HIV did not increase the frequency of detection or the amount of HIV DNA detected. HIV DNA was also detected in lymph nodes from some of the mice that were infected intravaginally with HSV-2 and HIV. Flow cytometric and mRNA analysis of human CD4 in vaginal tissue suggested that HSV-2 infection increased the number of T cells expressing human CD4 in vaginal tissue. This study provides evidence that HIV infection of cells occurs in the vagina of mice expressing human CD4, CCR5, and Cyclin T1 and that HSV-2 infection increases HIV infection. These findings demonstrate that this model can be used to study the mechanisms responsible for increased susceptibility to HIV in HSV-2-infected persons and for testing preventative treatments.
doi:10.1089/aid.2009.0035
PMCID: PMC2826840  PMID: 19886831
6.  Positive association between HIV RNA and IL-6 in the genital tract of Rwandan Women 
Infections and inflammation in the genital tract can influence HIV expression or HIV susceptibility. The goal of this study was to determine if significant relationships exist between cytokines and HIV in genital tract secretions from 57 HIV-seropositive Rwandan women. Genital tract secretions were obtained by cervicovaginal lavage (CVL). Ten different cytokines in CVL were measured by multiplex Cytometric Bead Arrays. HIV RNA in CVL and plasma were measured by quantitative PCR. In univariate analysis, genital tract HIV RNA was significantly associated with plasma HIV RNA and several of the cytokines, while in multivariate analysis, genital tract HIV RNA was only significantly associated with plasma HIV RNA and IL-6. This association of IL-6 with HIV RNA levels suggests that IL-6 is an indicator for conditions that induce HIV expression and that IL-6 may contribute to induction of HIV expression in the genital tract.
doi:10.1089/aid.2008.0004
PMCID: PMC2792594  PMID: 18671479
7.  Positive Association between HIV RNA and IL-6 in the Genital Tract of Rwandan Women 
Abstract
Infections and inflammation in the genital tract can influence HIV expression or HIV susceptibility. The goal of this study was to determine if significant relationships exist between cytokines and HIV in genital tract secretions from 57 HIV-seropositive Rwandan women. Genital tract secretions were obtained by cervicovaginal lavage (CVL). Ten different cytokines in CVL were measured by multiplex cytometric bead arrays. HIV RNA in CVL and plasma were measured by quantitative PCR. In univariate analysis, genital tract HIV RNA was significantly associated with plasma HIV RNA and several of the cytokines, while in multivariate analysis, genital tract HIV RNA was significantly associated only with plasma HIV RNA and IL-6. This association of IL-6 with HIV RNA levels suggests that IL-6 is an indicator for conditions that induce HIV expression and that IL-6 may contribute to induction of HIV expression in the genital tract.
doi:10.1089/aid.2008.0004
PMCID: PMC2792594  PMID: 18671479

Results 1-7 (7)