Altered Monocyte Phenotype in HIV-1 Infection Tends to Normalize with Integrase-Inhibitor-Based Antiretroviral Therapy

Background: Monocytes are increasingly implicated in the inflammatory consequences of HIV-1 disease, yet their phenotype following antiretroviral therapy (ART) initiation is incompletely defined. Here, we define more completely monocyte phenotype both prior to ART initiation and during 48 weeks of ART. Methods: Cryopreserved peripheral blood mononuclear cells (PBMCs) were obtained at baseline (prior to ART initiation) and at weeks 12, 24, and 48 of treatment from 29 patients participating in ACTG clinical trial A5248, an open label study of raltegravir/emtricitibine/tenofovir administration. For comparison, cryopreserved PBMCs were obtained from 15 HIV-1 uninfected donors, each of whom had at least two cardiovascular risk factors. Thawed samples were stained for monocyte subset markers (CD14 and CD16), HLA-DR, CCR2, CX3CR1, CD86, CD83, CD40, CD38, CD36, CD13, and CD163 and examined using flow cytometry. Results: In untreated HIV-1 infection there were perturbations in monocyte subset phenotypes, chiefly a higher frequency and density (mean fluorescence intensity–MFI) of HLA-DR (%-p = 0.004, MFI-p = .0005) and CD86 (%-p = 0.012, MFI-p = 0.005) expression and lower frequency of CCR2 (p = 0.0002) expression on all monocytes, lower CCR2 density on inflammatory monocytes (p = 0.045) when compared to the expression and density of these markers in controls’ monocytes. We also report lower expression of CX3CR1 (p = 0.014) on patrolling monocytes at baseline, compared to levels seen in controls. After ART, these perturbations tended to improve, with decreasing expression and density of HLA-DR and CD86, increasing CCR2 density on inflammatory monocytes, and increasing expression and density of CX3CR1 on patrolling monocytes. Conclusions: In HIV-1 infected patients, ART appears to attenuate the high levels of activation (HLA-DR, CD86) and to increase expression of the chemokine receptors CCR2 and CX3CR1 on monocyte populations. Circulating monocyte phenotypes are altered in untreated infection and tend to normalize with ART; the role of these cells in the inflammatory environment of HIV-1 infection warrants further study

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02 juillet 19201920/07/02 (A49).Appartient à l’ensemble documentaire : PoitouCh

Monocyte subset proportions at baseline and after ART initiation compared to proportions among controls.

<p>(A) Jitterplot comparing the subset proportions in HIV-1-infected individuals prior to ART initiation and subset proportions in controls. Medians are shown, and p values were determined using Mann Whitney U tests. Figs B-D display Tukey boxplots of medians and interquartile ranges. Outliers are shown as open circles. Tukey boxplots show the proportions of traditional monocytes (B), inflammatory monocytes (C) and patrolling monocytes (D) in controls (red) and in HIV-1-infected subjects at baseline and over the course of 48 weeks of ART.</p

Gating strategy for flow cytometry and comparison between fresh and cryopreserved monocyte surface marker expression.

<p>(A) Shown are isotype control dot plots and CD14 and CD16 expression in freshly obtained and cryopreserved PBMC from the same healthy volunteer and the expression of CX3CR1 on each monocyte subset in the cryopreserved sample. Monocyte subsets were gated using the isotype staining as a guide, as seen in the farthest left panel. Traditional monocytes are in purple, inflammatory monocytes are in pink, patrolling monocytes are in green. Gates are drawn based on negative isotype staining using Rat IgG2b, in the case of CX3CR1. (B) Summary surface marker expression, both proportion and MFI, in fresh and cryopreserved PBMCs on total monocytes of healthy control subjects, with medians, are shown. Each shape (triangle, square, diamond, and circle) represents an individual healthy control subject. (C) Summary surface marker expression, both proportion and MFI, in fresh and cryopreserved PBMCs on total monocytes of virologically suppressed HIV-infected subjects, with medians, are shown. Each shape (triangle, square, diamond, and circle) represents an individual HIV-infected subject.</p

Alterations in surface marker density on total monocytes and monocyte subsets of HIV-1-infected patients before and after initiation of ART.

<p>Baseline MFI values are italicized if significantly greater than among uninfected controls and boldedif significantly lower by Mann Whitney U tests. Comparisons were made between week 12 and baseline (0–12), week 24 and baseline (0–24), and week 48 and baseline (0–48) using both Wilcoxon signed rank test and the generalized estimating equation. Significant increases (p<0.05) are italicized and significant decreases are bolded. Robust Z score for the GEE plot are included to aid in the understanding of the direction of the change; negative Z score indicates decreased values after ART initiation and positive Z scores indicate increased values after ART initiation</p><p>Alterations in surface marker density on total monocytes and monocyte subsets of HIV-1-infected patients before and after initiation of ART.</p

Alterations in frequencies of surface marker expression on total monocytes and monocyte subsets of HIV-1-infected patients before and after initiation of ART.

<p>Baseline proportions are italicized if significantly greater than among uninfected controls and bolded if significantly lower by Mann Whitney U tests. Comparisons were made between week 12 and baseline (0–12), week 24 and baseline (0–24), and week 48 and baseline (0–48) using both Wilcoxon signed rank test and the generalized estimating equation. Significant increases (p<0.05) are italicized and significant decreases are bolded. Robust Z score for the GEE plot are included to aid in the understanding of the direction of the change; negative Z score indicates decreased values after ART initiation and positive Z scores indicate increased values after ART initiation.</p><p>Alterations in frequencies of surface marker expression on total monocytes and monocyte subsets of HIV-1-infected patients before and after initiation of ART.</p

Patient characteristics.

<p>HIV-1-infected patients are from the A5248 cohort and controls were taken from a cohort of uninfected persons with at least two cardiovascular disease risk factors.</p><p>Patient characteristics.</p

Systems biology of vaccination for seasonal influenza in humans.

Here we have used a systems biology approach to study innate and adaptive responses to vaccination against influenza in humans during three consecutive influenza seasons. We studied healthy adults vaccinated with trivalent inactivated influenza vaccine (TIV) or live attenuated influenza vaccine (LAIV). TIV induced higher antibody titers and more plasmablasts than LAIV did. In subjects vaccinated with TIV, early molecular signatures correlated with and could be used to accurately predict later antibody titers in two independent trials. Notably, expression of the kinase CaMKIV at day 3 was inversely correlated with later antibody titers. Vaccination of CaMKIV-deficient mice with TIV induced enhanced antigen-specific antibody titers, which demonstrated an unappreciated role for CaMKIV in the regulation of antibody responses. Thus, systems approaches can be used to predict immunogenicity and provide new mechanistic insights about vaccines