Altered Salivary Microbiome in the Early Stage of HIV Infections among Young Chinese Men Who Have Sex with Men (MSM)

Abstract

Human immunodeficiency virus (HIV) infections are spiking in Chinese young men who have sex with men (MSM). To explore alterations in the salivary microbiome and its correlation with demographic characteristics, CD4+ T cell count and viral load (VL) in HIV infections, samples of unstimulated whole saliva were analyzed by 16S rRNA gene sequencing using the Illumina MiSeq platform in 20 HIV newly infected patients before the initiation of antiretroviral therapy (ART) and at three and six months after, and in 20 age- and gender-paired healthy Chinese people. The results showed that the alpha diversity of salivary microbiota in HIV infections did not show differences from the healthy controls, but was reduced after six months under ART treatment. Comparative analysis revealed that Streptococcus was enriched in HIV-infected individuals, while Neisseria was enriched in the healthy control group. After effective ART, the salivary microbiota composition was not completely restored, although some microbiota recovered. In addition, we found Provotella_7, Neisseria and Haemophilus were correlated negatively with CD4+ T cell count, while Neisseria was correlated positively with VL. We conclude that HIV infections experience a dysbiosis of the salivary microbiome. The salivary microbiome test could be a substitute for the blood tests in the diagnosis and prognosis of diseases.

Alteration in Oral Microbiome Among Men Who Have Sex With Men With Acute and Chronic HIV Infection on Antiretroviral Therapy

“…Additionally, salivary components, such as salivary IgA, lactoferrin, defensins, and epithelial cell-mediated cytokines, are altered in PLWH, resulting in the occurrence of frequent oral infections (Muller et al, 1992). A recent study reported that the changes of salivary microbiome in HIV infection and found that Streptococcus was enriched in HIV-infected individuals, whereas the richness of Neisseria was high in healthy controls (Li et al, 2020). In present study, we observed that the abundance of unidentified Prevotellaceae in both groups of patients with acute and chronic HIV infection was increased as well as the abundances of Prevotella in acute HIV individuals and Streptococcus in chronic HIV individuals.…”

“…A previous study reported that Haemophilus parainfluenzae was significantly associated with HIV-positive individuals, and it was positively correlated with CD4 + T cell counts within the HIV-positive group (Kistler et al, 2015). However, a recent study found that the genus Haemophilus was correlated negatively with CD4 + T cell count (Li et al, 2020). The possible reasons for the different results might include the different study subjects, samples, the small sample sizes, and other possible factors not involved in the analysis.…”

“…Previous studies have also demonstrated that the abundance and diversity of oral microbiomes in PLWH were significantly different from those observed in healthy controls. Indeed after ART, the oral microbiome composition was not completely recovered, although it turned to be similar to that observed in healthy controls (Presti et al, 2018;Li et al, 2020). It is known that the composition and homeostasis of oral microbiome are affected by multiple factors, such as diet, medication, and host responses (Samaranayake and Matsubara, 2017).…”

“…Although the similar oral microbiome composition has been reported between the HIV-infected individuals undergoing ART and healthy controls, there are significant differences (Li et al, 2020). In the longitudinal study, we collected samples from acute and chronic HIV-infected MSM at baseline and 12 weeks of ART.…”

Differential Signature of the Microbiome and Neutrophils in the Oral Cavity of HIV-Infected Individuals

“…Since all of our study subjects for the oral microbiome-related studies were on ART, we were unable to investigate the potential effects of ART on the oral microbiome. However, it was reported that the dysbiotic oral microbiome was not fully restored after effective ART, although some microbiota were restored ( 51 ). Furthermore, ART, viral load, and CD4 + T cell count differentially contribute to salivary dysbiosis resulting in reduced or increased different bacterial species ( 27 ).…”