Circulating levels and ex vivo production of beta-chemokines, interferon gamma, and interleukin 2 in advanced human immunodeficiency virus type 1 infection: the effect of protease inhibitor therapy

Association of Antiretroviral Therapy with Platelet Function and Systemic Inflammatory Response in People Living with HIV: A Cross-Sectional Study

People living with HIV (PLWHIV) present an increased risk of adverse cardiovascular events. We aimed to assess whether antiretroviral therapy (ART) pharmacologically enhances platelet reactivity and platelet activation intensity, and explore the potential association with underlying inflammatory status. This was a cross-sectional cohort study carried out among PLWHIV on diverse ART regimens. Platelet reactivity and activation intensity were assessed using the bedside point-of-care VerifyNow assay, in P2Y12 reaction units (PRU), measurements of monocyte-platelet complexes, and P-selectin and GPIIb/IIIa expression increase, following activation with ADP, respectively. Levels of major inflammatory markers and whole blood parameters were also evaluated. In total, 71 PLWHIV, 59 on ART and 22 healthy controls, were included in this study. PRU values were significantly elevated in PLWHIV compared to controls [Mean; 257.85 vs. 196.67, p < 0.0001], but no significant differences were noted between ART-naïve or ART-experienced PLWHIV, or between TAF/TDF and ABC based regimens, similar to systemic inflammatory response. However, within-group analysis showed that PRUs were significantly higher in ABC/PI vs ABC/INSTI or TAF/TDF + PI patients, in line with levels of IL-2. PRU values did not correlate strongly with CD4 counts, viral load, or cytokine values. P-selectin and GPIIb/IIIa expression increased following ADP activation and were significantly more prominent in PLWHIV (p < 0.005). Platelet reactivity and platelet activation intensity were shown to be increased in PLWHIV, but they did not appear to be related to ART initiation, similar to the underlying systemic inflammatory response.

Platelet activation in adult HIV-infected patients on antiretroviral therapy: a systematic review and meta-analysis

BACKGROUND

Antiretroviral therapy (ART) alters platelet reactivity, and as a consequence, patients living with HIV may be at an increased risk of cardiovascular disease (CVD). The current evidence on platelet activation levels in patients with HIV remains inconclusive. We therefore aimed to systematically synthesise evidence on the association of platelet activation in HIV-infected patients on successful treatment.

METHODS

Electronic databases were searched from inception until November 2019. Studies were included if the primary or secondary outcome of the study was to assess platelet activation in HIV-infected patients on ART. The primary outcome of this review included the levels of platelet activation. The pooled effect estimates were calculated using a random-effects meta-analysis model.

RESULTS

We identified 30 studies comprising of 2325 participants. The pooled estimates showed elevated levels of platelet activation in treatment-naïve HIV-infected patients compared to uninfected controls (Hedges' g 2.00 [95%CI 1.05, 2.94]; z = 4.12, p < 0.0001). These remained elevated despite successful ART (Hedges' g 2.05 [95%CI 0.58, 3.52]; z = 2.71, p = 0.0067).

CONCLUSION

The levels of platelet activation are elevated in treatment-naïve HIV-infected patients, and these persist during successful ART. Further studies should assess the clinical relevance of monitoring the levels of platelet activation in HIV-infected patients on ART.

Impact of antiretroviral drugs on PD-L1 expression and copy number gains with clinical outcomes in HIV-positive and -negative locally advanced cervical cancers

Cervical cancer has become a leading cause of death in both HIV-infected and uninfected women. Previous studies have revealed that antiretroviral therapy (ART) possesses anti-human papillomavirus (HPV) and antitumour properties, potentially serving as an anticancer agent and improving functional immunity in HIV-positive individuals. However, to the best of our knowledge, no studies have examined the association between ART and the clinical outcome of patients with pre-existing invasive cervical cancer. The current study analysed 48 HIV-positive and 123 HIV-negative patients with locally advanced stage IB2-IVA cervical cancer between December 2008 and December 2016. Tumours were categorized based on programmed cell death-ligand 1 (PD-L1) immunoreactivity and copy number alterations in the PD-L1 gene, as determined by fluorescence in situ hybridization. The results revealed that ART-treated patients exhibited a lower prevalence of PD-L1 immunopositivity, PD-L1 amplification and polysomy compared with patients that did not receive ART and those that were HIV-negative. Furthermore, ART-treated patients with PD-L1 immunonegativity exhibited an improved recurrence-free survival (RFS) compared with patients that did not receive ART and HIV-negative individuals with PD-L1 immunopositivity (P=0.041 vs. P=0.030). Additionally, ART-exposed patients with PD-L1 disomy demonstrated improved locoregional recurrence-free survival (LRR) when compared with HIV-negative patients with PD-L1 amplification and polysomy (P=0.039 vs. P=0.007), RFS (P<0.001 vs. P=0.006) and cancer-specific survival (CSS) (P=0.021 vs. P=0.025). ART-exposed patients with PD-L1 disomy also exhibited improved RFS (P<0.001) and CSS (P<0.001) compared with HIV-negative patients with PD-L1 amplification. Improved LRRs were demonstrated in ART-exposed patients with PD-L1 disomy (P=0.028) compared with non-HIV patients with polysomy. Following multivariate analysis, International Federation of Gynaecology and Obstetrics stage and PD-L1 amplification were determined to be predictors of poor a RFS [hazard ratio (HR), 2.43; 95% confidence interval (CI), 1.37–4.30; P=0.002 vs. HR, 7.03; 95% CI, 2.79–17.74; P<0.001) and CSS (HR, 11.47; 95% CI, 4.70–27.99; P<0.001 vs. HR, 4.05; 95% CI, 1.64–9.98; P=0.002). However, only PD-L1 polysomy was determined to be a predictor of poor LRR (HR, 2.50; 95% CI, 1.11–5.63; P=0.027). HIV status was not associated with poor outcomes, as determined using Cox models. The results of the current study indicated that ART may be used for the treatment of cervical cancer in both HIV-infected and uninfected patients. However, additional research is required to further elucidate these results.

CD4 and Chemokine Receptors on Human Brain Microvascular Endothelial Cells, Implications for Human Immunodeficiency Virus Type 1 Pathogenesis

Central nervous system (CNS) dysfunction is commonly observed in children with human immunodeficiency virus type 1 (HIV-1) infection, but the mechanism(s) whereby HIV-1 causes encephalopathy remains incompletely understood. Human brain microvascular endothelial cells (HBMECs), which constitute the blood-brain barrier, are likely to contribute to HIV-1 encephalopathy, but it is unclear whether HIV-1 receptors (CD4, chemokine receptors) are present on HBMECs. In the present study, the presence of CD4 in six different children was demonstrated. Moreover, the presence of CD4 in situ on brain sections was shown. Distribution of CD4 expression was heterogeneous among microvessels; staining for CD4 was strong in some vessels and absent in other adjacent vessels. CD4 and chemokine coreceptors were found to be functional as intercellular adhesion molecule (ICAM)-1 expression increased upon incubation of HBMECs with activating anti-CD4 and anti-chemokine receptor antibodies. The presence of CD4 and chemokine receptors in human brain endothelium of children may have implications for the pathogenesis of HIV-1 encephalopathy and explain the higher incidence of CNS involvement in HIV-1-infected children as compared to adults.

Lack of good correlation of serum CC-chemokine levels with human immunodeficiency virus-1 disease stage and response to treatment

Three CC-chemokines-MIP-1alpha (CCL3), MIP-1beta (CCL4), and RANTES (CCL5)-are natural ligands for the human immunodeficiency virus-1 (HIV-1) coreceptor CCR5. To determine correlations between CC-chemokines and HIV-1 disease stage or response to treatment, we examined serum levels of MIP-1alpha, MIP-1beta, and RANTES in 60 infected patients during 18 months while they were taking highly active antiretroviral therapy (HAART). Our results demonstrate that serum levels of MIP-1alpha and RANTES were increased in HIV-1-infected individuals compared with those in healthy controls. We found no significant differences among 4 clinical stages of HIV-1 infection in the serum levels of three CC-chemokines. Longitudinal HAART analyses revealed a pronounced decline in serum MIP-1alpha levels over time. We found no difference in this decline between HAART responders and nonresponders. These findings indicate that production of MIP-1alpha and RANTES changes during HIV-1 infection and treatment; however, our results suggest that serum levels of CC-chemokines should not be used as biomarkers for HIV-1 disease stage or response to treatment.

Immune intervention strategies for HIV-1 infection of humans in the SIV macaque model

Studies in the SIVmac macaque model have demonstrated that the extent of virus-specific CD4+ and CD8+ T-cell responses induced by vaccination prior to virus-challenge exposure correlate with viremia containment following establishment of infection. These findings led to the hypothesis that active immunization with vaccines able to induce virus-specific T-cell responses following the establishment of infection could also ameliorate the virological outcome. Here, we will review the relative effect of ART and vaccination during primary SIVmac infection of macaques.