Evaluation of HIV-specific T-cell responses in HIV-infected older patients with controlled viremia on long-term antiretroviral therapy

Plasma Levels of Secreted Cytokines in Virologically Controlled HIV-Infected Aging Adult Individuals on Long-Term Antiretroviral Therapy

HIV-infected (HIV+) aging adult individuals who have achieved undetectable viral load and improved CD4 T cell counts due to long-term antiretroviral therapy (ART) may continue to experience inflammation and immunosenescence. Therefore, we evaluated the plasma levels of proinflammatory and anti-inflammatory cytokines in 173 HIV+ aging adult individuals with age ranging from 22 to 81 years on long-term ART with viral load mostly <20 HIV RNA copies/mL and compared with 92 HIV-uninfected (HIV- or healthy controls) aging individuals. We found that the median levels of TNF-α, IFN-γ, IL-1β, IL-6, and IL-10 were higher (p < 0.001 to <0.0001) and IL-17 trended lower in HIV+ individuals than healthy controls. Increasing CD4 T cell counts in the HIV+ cohort did not significantly change the circulating cytokine levels, although levels of IL-1β increased. However, IL-17 levels significantly decreased with increasing CD4 counts in the healthy controls and yet unchanged in the HIV+ cohort. Of note, the levels of circulating IL-17 were significantly reduced comparatively in the healthy controls where the CD4 count was below 500, yet once above 500 the levels of CD4, IL-17 levels were comparable with the HIV+ cohort. With increasing CD8 T cell counts, the levels of these cytokines were not significantly altered, although levels of TNF-α, IFN-γ, and IL-6 declined, whereas IL-1β and IL-17 were slightly elevated. Furthermore, increasing age of the HIV+ cohort did not significantly impact the cytokine levels although a slight increase in TNF-α, IL-6, IL-10, and IL-17 was observed. Similarly, these cytokines were not significantly modulated with increasing levels of undetectable viral loads, whereas some of the HIV+ individuals had higher levels of TNF-α, IFN-γ, and IL-1β. In summary, our findings show that HIV+ aging adult individuals with undetectable viral load and restored CD4 T cell counts due to long-term ART still produce higher levels of both proinflammatory and anti-inflammatory cytokines compared with healthy controls, suggesting some level of inflammation.

Modelling the impact of protein-kinase R allelic variant on HIV biomarkers trajectories by means of latent class mixed models

This paper is based on a retrospective longitudinal study on people living with HIV under antiretroviral treatment (ART) where allelic variants (either heterozygous CT genotype or homozygous CC genotype) have been evaluated at position -168 of the promoter region of the protein kinase R (-168/PKR). In general, antiviral effects of interferon are partially mediated by a RNA-dependent protein kinase (PKR) that, once activated, inhibits protein synthesis. Indeed, activation of PKR response can inhibit HIV replication. To explore the role of allelic variants in shaping dynamics of commonly monitored HIV biomarkers, CD4 cells, CD8 cells and HIV-load were modelled within a latent class mixed model (LCMM) to account for participants' heterogeneity over time. The estimated models identified two sub-groups from CD4 and HIV-load dynamics, revealing better outcomes for subgroups of participants with the heterozygous CT genotype. Heterozygous CT subjects in one of the two identified subgroups exhibited higher increase of CD4 cells and more marked decrease of HIV-load, over time, with respect to the homozygous CC subjects assigned to the same group.

Design and validation of HIV peptide pools for detection of HIV-specific CD4+ and CD8+ T cells

Reagents to monitor T cell responses to the entire HIV genome, based on well characterized epitopes, are missing. Evaluation of HIV-specific T cell responses is of importance to study natural infection, and therapeutic and vaccine interventions. Experimentally derived CD4+ and CD8+ HIV epitopes from the HIV molecular immunology database were developed into Class I and Class II HIV megapools (MPs). We assessed HIV responses in persons with HIV pre antiretroviral therapy (ART) (n = 17) and post-ART (n = 18) and compared these responses to 15 controls without HIV (matched by sex at birth, age, and ethnicity). Using the Activation Induced Marker (AIM) assay, we quantified HIV-specific total CD4+, memory CD4+, circulating T follicular helper, total CD8+ and memory CD8+ T cells. We also compared the Class I and Class II HIV MPs to commercially available HIV gag peptide pools. Overall, HIV Class II MP detected HIV-specific CD4+ T cells in 21/35 (60%) HIV positive samples and 0/15 HIV negative samples. HIV Class I MP detected an HIV-specific CD8+ T cells in 17/35 (48.6%) HIV positive samples and 0/15 HIV negative samples. Our innovative HIV MPs are reflective of the entire HIV genome, and its performance is comparable to other commercially available peptide pools. Here, we detected HIV-specific CD4+ and CD8+ T cell responses in people on and off ART, but not in people without HIV.

Genetic Analysis of HIV-1 vpr Sequences from HIV-Infected Older Patients on Long-Term Antiretroviral Therapy

BACKGROUND

Many HIV-infected individuals have achieved undetectable viral load and increased CD4 T cell counts due to the success of Antiretroviral Therapy (ART). However, HIV persists in resting T cells, monocytes/macrophages and other quiescent cells. Furthermore, the HIV- 1 vpr accessory gene may play an important role in the persistence of HIV in these infected patients.

OBJECTIVES

Therefore, we characterized the HIV-1 vpr gene from PBMC DNA of 14 HIV-infected older patients on long-term ART with mostly undetectable viral load and increased CD4 T cell counts.

METHODS

Peripheral Blood Mononuclear Cells (PBMC) were isolated from 14 HIV-infected individuals, followed by extraction of genomic DNA, amplification of HIV-1 vpr gene by polymerase chain reaction (PCR), cloning of vpr gene in TOPO vector and characterization of correct size recombinant inserts containing vpr genes. An average of 13 clones were sequenced from each patient, followed by sequence analysis by bioinformatic tools.

RESULTS

Phylogenetic analysis of 182 vpr sequences demonstrated that the vpr sequences of each patient were well separated and discriminated from other patients' sequences and formed distinct clusters. The vpr sequences showed a low degree of viral heterogeneity, lower estimates of genetic diversity and about half of the patients' sequences were under positive selection pressure. While the majority of the vpr deduced amino acid sequences from most patients contained intact open reading frames, several sequences, mostly from two patients, had stop codons. Numerous patient-specific and common amino acid motifs were found in deduced vpr sequences. The functional domains required for vpr activity, including virion incorporation, nuclear import of pre-integration complex and cell cycle arrest, were generally conserved in most vpr sequences. Several of the known Cytotoxic T-lymphocytes (CTL) epitopes in vpr showed variation in our patients' sequences.

CONCLUSION

In summary, a low degree of genetic variability, conservation of functional domains and variations in CTL epitopes were the features of vpr sequences from the 14 HIV-infected older patients with controlled viremia on long-term ART.

Phenotypic frailty in people living with HIV is not correlated with age or immunosenescence

Background

It has been hypothesized that HIV-1 infection prematurely “ages” individuals phenotypically and immunologically. We measured phenotypic frailty and immune “aging” markers on T-cells of people living with HIV on long term, suppressive anti-retroviral therapy (ART) to determine if there is an association between frailty and immunosenescence.

Methods

Thirty-seven (37) community-dwelling people living with HIV were measured for frailty using a sensor-based frailty meter that quantifies weakness, slowness, rigidity, and exhaustion. An immunological profile of the patients’ CD4⁺ and CD8⁺ T-cell expression of cell surface proteins and cytokines was performed (n = 20).

Results

Phenotypic frailty prevalence was 19% (7/37) and correlated weakly with the number of past medical events accrued by the patient (r = 0.34, p = .04). There was no correlation of frailty with age, sex, prior AIDS diagnosis or HIV-1 viral load, or IFN-γ expression by CD4⁺ or CD8⁺ T-cells. There were more immune competent (CD28⁺ CD57⁻) cells than exhausted/senescent (CD28⁻ CD57⁺) T cells.

Conclusion

Frailty in people living with HIV on long term, suppressive ART did not correlate with aging or T cell markers of exhaustion or immunosenescence.

Significance of Vascular Cell Adhesion Molecule-1 and Tumor Necrosis Factor-Alpha in HIV-Infected Patients

Background. The aim of this study was the evaluation of the correlation between VCAM-1 and TNF-alpha serum concentrations and various clinical and laboratory parameters in HIV-infected patients. Methods. All included subjects were patients of the Department of Infectious and Tropical Diseases and Hepatology of the Medical University of Warsaw in Poland in the years 2014–2016. The inclusion criteria were: confirmed HIV infection, Caucasian origin, and age > 18 years old. PCT, CRP, serum HIV-1 RNA, CD4/CD8 T cell count, PCR HCV RNA, HBsAg, VCAM-1, and TNF-alpha were measured. The VCAM-1 and TNF-alpha serum levels were evaluated by ELISA. Results. Seventy-two HIV-infected patients were included (16 women and 56 men: mean age 38.7 years, 66.6% cigarette smokers, 34.7% HCV co-infected HCV, and 27.8% ART-naïve). VCAM-1 concentrations were significantly higher in HIV/HCV co-infected patients than in HIV mono-infected patients (125.6 ± 85.4 vs. 78.4 ± 58.6 ng/mL, p = 0.011) and ART-naïve in comparison to patients on cART (121.9 ± 76.5 vs. 69.4 ± 57.1 ng/mL, p = 0.003). The significant positive correlation between HCV-infection and VCAM-1 and negative correlation between cART use and VCAM-1 was confirmed in multivariate analyses. The only variable associated significantly with TNF-alpha concentration was lymphocytes T CD8+ cell count (p = 0.026, estimate = 0.033). Conclusions. Successful cART and HCV eradication seemed to play an important role in the reduction of endothelial dysfunction and persistent inflammation in HIV-infected patients. CD8 T cell count seemed to be one of the markers of the pro-inflammatory state in HIV-infection patients.

Comparison of analgesic modalities for patients undergoing midline laparotomy: a systematic review and network meta-analysis

BACKGROUND

Midline laparotomy is associated with severe pain. Epidural analgesia has been the established standard, but multiple alternative regional anesthesia modalities are now available. We aimed to compare continuous and single-shot regional anesthesia techniques in this systematic review and network meta-analysis.

METHODS

We included randomized controlled trials on adults who were scheduled for laparotomy with solely a midline incision under general anesthesia and received neuraxial or regional anesthesia for pain. Network meta-analysis was performed with a frequentist method, and continuous and dichotomous outcomes were presented as mean differences and odds ratios, respectively, with 95% confidence intervals. The quality of evidence was rated with the  grading of recommendations, assessment, development, and evaluation system.

RESULTS

Overall, 36 trials with 2,056 patients were included. None of the trials assessed erector spinae plane or quadratus lumborum block, and rectus sheath blocks and transversus abdominis plane blocks were combined into abdominal wall blocks (AWB). For the co-primary outcome of pain score at rest at 24 hr, with a minimal clinically important difference (MCID) of 1, epidural was clinically superior to control and single-shot AWB; epidural was statistically but not clinically superior to continuous wound infiltration (WI); and no statistical or clinical difference was found between control and single-shot AWB. For the co-primary outcome of cumulative morphine consumption at 24 hr, with a MCID of 10 mg, epidural and continuous AWB were clinically superior to control; epidural was clinically superior to continuous WI, single-shot AWB, single-shot WI, and spinal; and continuous AWB was clinically superior to single-shot AWB. The quality of evidence was low in view of serious limitations and imprecision. Other results of importance included: single-shot AWB did not provide clinically relevant analgesic benefit beyond two hr; continuous WI was clinically superior to single-shot WI by 8-12 hr; and clinical equivalence was found between epidural, continuous AWB, and continuous WI for the pain score at rest, and epidural and continuous WI for the cumulative morphine consumption at 48 hr.

CONCLUSIONS

Single-shot AWB were only clinically effective for analgesia in the early postoperative period. Continuous regional anesthesia modalities increased the duration of analgesia relative to their single-shot counterparts. Epidural analgesia remained clinically superior to alternative continuous regional anesthesia techniques for the first 24 hr, but reached equivalence, at least with respect to static pain, with continuous AWB and WI by 48 hr.

TRIAL REGISTRATION

PROSPERO (CRD42021238916); registered 25 February 2021.

Characterization of HIV-1 Envelope V3 Region Sequences from Virologically Controlled HIV-Infected Older Patients on Long Term Antiretroviral Therapy

Although many HIV-infected patients have attained older age owing to the success of antiretroviral therapy (ART) in controlling viremia and increasing CD4 T cell counts, HIV continues to persist in several target cells. We have characterized 514 HIV-1 envelope V3 region sequences (94-96 amino acids [aa]) from 25 HIV-infected older patients' peripheral blood mononuclear cell DNA on long-term ART with controlled viremia (undetectable viral load) and improved CD4 T cell counts. Phylogenetic analysis revealed that the V3 region sequences of each patient formed distinct clusters that were well separated and discriminated from other patients' sequences. The coding potential of the V3 region, including several patient-specific amino acid motifs and functional domains, including the two cysteines sandwiching the V3 loop, the central GPGR motif with variation at one position in some sequences, the base GDIR motif, and the N-glycosylation sites were generally conserved. The patients' V3 region sequences contained amino acid motifs conferring affinity mostly for CCR5 coreceptor, suggesting R5 phenotype. There was a low degree of heterogeneity and lower estimates of genetic diversity in all 25 patients' V3 region sequences. Twelve of 25 patients' V3 region sequences were found to be under positive selection pressure. Analysis of the several cytotoxic T lymphocytes (CTL) epitopes showed variation, whereas some of known neutralizing antibodies (nAbs) epitopes showed conservation in patients' V3 region sequences. In conclusion, a low degree of genetic variability and maintenance of functional domains with R5 phenotypes, and variation in CTL and conservation of nAb epitopes were the hallmarks of V3 region sequences from our 25 virologically controlled HIV-infected older patients on long-term ART.