Almost all individuals infected with human immunodeficiency virus (HIV) are also infected with cytomegalovirus (CMV) and Epstein Barr virus (EBV). The aims of our studies have included characterizing ...and measuring the latent HIV reservoir and understanding the association between asymptomatic replication of CMV (and other herpesvirus, including EBV) and this HIV reservoir (Gianella
, 2014). This protocol was designed to simultaneously co-extract DNA and RNA from the same peripheral blood mononuclear cell (PBMC) aliquot and quantify HIV, CMV and EBV DNA, as well as HIV RNA using droplet digital PCR (ddPCR). For collection and processing of male genital secretions and quantification of HIV RNA and DNA from seven human herpesviruses from seminal plasma, refer to protocol "Quantification of HIV RNA and Human Herpesvirus DNA in Seminal Plasma" (Vargas-Meneses
, 2015).
Multiple viruses can co-infect the genital tract, modifying the immunologic and virologic milieu and possibly playing a role in viral transmission and pathogenesis. The aim of our studies has been to ...understand the complex relationships between HIV-1 RNA, and multiple human herpesviruses known to frequently replicate in the genital tract of HIV-infected men (
cytomegalovirus CMV, Epstein Bar virus EBV, herpes simplex virus HSV types 1 and 2, and human herpesviruses HHV 6, 7 and 8) (Gianella
, 2013a; Gianella
, 2013b; Gianella
, 2013c; Gianella
, 2014). This protocol was designed to collect and process male genital secretion (GS), and to isolate and further quantify HIV RNA and DNA of seven HHV from seminal plasma using quantitative real time PCR technology.
The protective effect of neutralizing antibodies in SARS-CoV-2 infected individuals is not yet well defined. To address this issue, we have analyzed the kinetics of neutralizing antibody responses ...and their association with disease severity. Between March and May 2020, the prospective KING study enrolled 72 COVID-19+ participants grouped according to disease severity. SARS-CoV-2 infection was diagnosed by serological and virological tests. Plasma neutralizing responses were assessed against replicative virus and pseudoviral particles. Multiple regression and non-parametric tests were used to analyze dependence of parameters. The magnitude of neutralizing titers significantly increased with disease severity. Hospitalized individuals developed higher titers compared to mild-symptomatic and asymptomatic individuals, which together showed titers below the detection limit in 50% of cases. Longitudinal analysis confirmed the strong differences in neutralizing titers between non-hospitalized and hospitalized participants and showed rapid kinetics of appearance of neutralizing antibodies (50% and 80% of maximal activity reached after 11 and 17 days after symptoms onset, respectively) in hospitalized patients. No significant impact of age, gender or treatment on the neutralizing titers was observed in this limited cohort. These data identify a clear association of humoral immunity with disease severity and point to immune mechanisms other than antibodies as relevant players in COVID-19 protection.
Whereas human immunodeficiency virus (HIV) persists in tissue macrophages during antiretroviral therapy (ART), the role of circulating monocytes as HIV reservoirs remains controversial. Three ...magnetic bead selection methods and flow cytometry cell sorting were compared for their capacity to yield pure CD14
monocyte populations. Cell sorting by flow cytometry provided the purest population of monocytes (median CD4
T-cell contamination, 0.06%), and the levels of CD4
T-cell contamination were positively correlated with the levels of integrated HIV DNA in the monocyte populations. Using cell sorting by flow cytometry, we assessed longitudinally the infection of monocytes and other cell subsets in a cohort of 29 Thai HIV-infected individuals. Low levels of HIV DNA were detected in a minority of monocyte fractions obtained before and after 1 year of ART (27% and 33%, respectively), whereas HIV DNA was readily detected in CD4
T cells from all samples. Additional samples (2 to 5 years of ART) were obtained from 5 individuals in whom monocyte infection was previously detected. Whereas CD4
T cells were infected at high levels at all time points, monocyte infection was inconsistent and absent in at least one longitudinal sample from 4/5 individuals. Our results indicate that infection of monocytes is infrequent and highlight the importance of using flow cytometry cell sorting to minimize contamination by CD4
T cells.
The role of circulating monocytes as persistent HIV reservoirs during ART is still controversial. Several studies have reported persistent infection of monocytes in virally suppressed individuals; however, others failed to detect HIV in this subset. These discrepancies are likely explained by the diversity of the methods used to isolate monocytes and to detect HIV infection. In this study, we show that only flow cytometry cell sorting yields a highly pure population of monocytes largely devoid of CD4 contaminants. Using this approach in a longitudinal cohort of HIV-infected individuals before and during ART, we demonstrate that HIV is rarely found in monocytes from untreated and treated HIV-infected individuals. This study highlights the importance of using methods that yield highly pure populations of cells as flow cytometry cell sorting to minimize and control for CD4
T-cell contamination.
OBJECTIVES:Curative strategies using agents to perturb the HIV reservoir have demonstrated only modest activity, whereas increases in viremia after standard vaccination have been described. We ...investigated whether vaccination against non-HIV pathogens can induce HIV transcription and thereby play a role in future eradication strategies.
DESIGN:A randomized controlled trial (NCT00329251) was performed to compare the effects of clinical vaccines with placebo on HIV transcription and immune activation.
METHODS:Twenty-six HIV-infected individuals on suppressive antiretroviral therapy were randomized to receive a vaccination schedule (n = 13) or placebo (n = 13). Cell-associated RNA and DNA were extracted from peripheral blood mononuclear cells, and HIV was quantified by droplet digital PCR using primers for gag and 2-LTR (for HIV DNA), unspliced gag RNA (gag usRNA), multispliced tat-rev RNA (tat-rev msRNA) and polyA mRNA.
RESULTS:Significant increases in gag usRNA after influenza/hepatitis B vaccination (P = 0.02) and in gag usRNA (P = 0.04) and polyA mRNA (P = 0.04) after pneumococcus/hepatitis B vaccination were seen in vaccinees but not controls. HIV DNA and plasma HIV RNA did not change in either group. Increases in CD4 and CD8 T-cell activation markers (P = 0.08 and P < 0.001, respectively) and HIV-specific CD8 responses (P = 0.04 for p24 gag, P = 0.01 for p17 gag and P = 0.04 for total gag) were seen in vaccinees but not controls.
CONCLUSION:In this study, vaccination was associated with increases in HIV cell-associated RNA and HIV-specific responses during antiretroviral therapy. Using standard vaccines to stimulate HIV transcription may therefore be a useful component of future eradication strategies.
We analyzed humoral and cellular immune responses induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA) vaccines in people with human immunodeficiency virus ...(HIV; PWH) who had CD4+ T-cell counts <200/µL (HIV<200 group).
This prospective cohort study included 58 PWH in the HIV<200 group, 36 with CD4+ T-cell counts >500/µL (HIV>500 group), and 33 HIV-1-negative controls (control group). Antibodies against the SARS-CoV-2 spike protein (anti-S immunoglobulin Ig G) and the receptor-binding domain (anti-RBD IgG) were quantified before and 4 weeks after the first and the second doses of BNT162b2 or mRNA-1273 (at week 8). Viral neutralization activity and T-cell responses were also determined.
At week 8, anti-S/anti-RBD IgG responses increased in all groups (P < .001). Median (interquartile range) anti-S and anti-RBD IgG levels at week 8 were 153.6 (26.4-654.9) and 171.9 (61.8-425.8) binding antibody units (BAU)/mL, respectively, in the HIV<200 group, compared with 245.6 (145-824) and 555.8 (166.4-1751) BAU/mL in the HIV>500 group and 274.7 (193.7-680.4) and 281.6 (181-831.8) BAU/mL in controls (P < .05). Neutralizing capacity and specific T-cell immune responses were absent or reduced in 33% of those in the HIV<200 group, compared with 3.7% in the HIV>500 group (P < .01).
One-third of PWH with CD4+ T-cell counts <200/µL show low anti-S/anti-RBD IgG levels, reduced in vitro neutralization activity against SARS-CoV-2, and no vaccine-induced T cells after receiving coronavirus disease 2019 mRNA vaccines.
Early HIV infection is characterized by a dramatic depletion of CD4 T cells in the gastrointestinal tract and translocation of bacterial products from the gut into the blood. In this study, we ...evaluated if gut bacterial profiles were associated with immune status before and after starting antiretroviral therapy (ART).
We evaluated the gut microbiota of men recently infected with HIV (n = 13) who were participating in a randomized, double-blind controlled trial of combination ART and maraviroc versus placebo and who were followed for 48 weeks.
To evaluate the gut microbiota of participants, we pyrosequenced the bacterial populations from anal swabs collected before and longitudinally after the initiation of ART. Associations of the gut flora with clinical variables (lymphocyte profiles and viral loads), activation and proliferation markers in peripheral blood mononuclear cells and gut biopsies (measured by flow cytometry) and markers of microbial translocation (lipopolysaccharide and soluble CD14) were performed by regression analyses using R statistical software.
Using pyrosequencing, we identified that higher proportions of Lactobacillales in the distal gut of recently HIV-infected individuals were associated with lower markers of microbial translocation, higher CD4% and lower viral loads before ART was started. Similarly, during ART, higher proportions of gut Lactobacillales were associated with higher CD4%, less microbial translocation, less systemic immune activation, less gut T lymphocyte proliferation, and higher CD4% in the gut.
Shaping the gut microbiome, especially proportions of Lactobacillales, could help to preserve immune function during HIV infection.
Understanding mid-term kinetics of immunity to SARS-CoV-2 is the cornerstone for public health control of the pandemic and vaccine development. However, current evidence is rather based on limited ...measurements, losing sight of the temporal pattern of these changes.
We conducted a longitudinal analysis on a prospective cohort of COVID-19 patients followed up for >6 months. Neutralizing activity was evaluated using HIV reporter pseudoviruses expressing SARS-CoV-2 S protein. IgG antibody titer was evaluated by ELISA against the S2 subunit, the receptor binding domain (RBD), and the nucleoprotein (NP). Statistical analyses were carried out using mixed-effects models.
We found that individuals with mild or asymptomatic infection experienced an insignificant decay in neutralizing activity, which persisted 6 months after symptom onset or diagnosis. Hospitalized individuals showed higher neutralizing titers, which decreased following a 2-phase pattern, with an initial rapid decline that significantly slowed after day 80. Despite this initial decay, neutralizing activity at 6 months remained higher among hospitalized individuals compared to mild symptomatic. The slow decline in neutralizing activity at mid-term contrasted with the steep slope of anti-RBD, S2, or NP antibody titers, all of them showing a constant decline over the follow-up period.
Our results reinforce the hypothesis that the quality of the neutralizing immune response against SARS-CoV-2 evolves over the post-convalescent stage.
The failure to increase CD4 T-cell counts in some HAART-treated HIV-infected patients with satisfactory virological responses has been related to low CD4 T-cell production, high turnover and death. ...However, the relative contribution of these factors is still unclear, strongly limiting the definition of appropriate therapeutic strategies for these patients.
A cross-sectional study was designed to evaluate the contribution of thymic activity, microbial translocation, cellular activation and death to CD4 T-cell recovery. We included 230 HIV-infected individuals on suppressive HAART (>2 years); 95 of them were considered 'discordant' (CD4 T-cell count <350 cells/mul) and 135 were considered 'concordant'. Comparative and logistic regression analyses were performed.
Discordant patients showed higher levels of activated human leukocyte antigen (HLA)-DRCD95 and CD38CD45RA cells in both the CD8 and CD4 T-cell compartments. Notably, the most significant differences were observed in CD4 T cells. Discordant patients showed lower naive CD4 T-cell production (CD45RACD31 cells), higher spontaneous ex-vivo CD4 T-cell death and higher plasma levels of soluble CD14. Multivariate analysis showed that activation and death of CD4 T cells, along with nadir CD4 T-cell counts, were the only predictive factors for poor immune recovery. Moreover, the low correlations found between CD4 T-cell activation or death with thymic output and bacterial translocation suggest that additional factors modulate cellular activation and death and, in turn, CD4 T-cell recovery.
CD4 T-cell repopulation during HAART is determined by CD4 T-cell activation and death. Therefore, strategies aimed to reduce these parameters should be envisaged to treat discordant patients.
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