Background: Idiopathic CD4+ lymphocytopenia is defined by a stable decrease of CD4+ T cells in the absence of any known cause of immune deficiency. The mechanisms responsible for the immunological impairment are still unknown, but a regenerative failure of hematopoietic stem/progenitor cells has been hypothesized. Methods: We evaluated in the bone marrow (BM) of 5 patients with idiopathic CD4+ lymphocytopenia the phenotype of BM progenitor cells, their differentiation capacity with colony-forming cells and long-term culture-initiating cell assays, in parallel with the spontaneous IL-7 production in the patient sera. Results: Compared with controls, a regenerative failure of hematopoietic stem cells has been observed, both in ‘committed’ and in ‘uncommitted’ progenitor cells, despite high IL-7 serum levels. The percentage of phenotypically primitive CD34+CD38–DR+ cells (this includes the lymphoid precursor cells) was decreased, suggesting an involvement of the more primitive BM compartment in the de novo T cell generation. Conclusions: Despite the low number of patients, due to the low incidence of the disease, the decrease of primitive precursors sustains the possibility that diminished stem cell precursors might contribute to the development of CD4+ T cell depletion.

Abstract:The human immunodeficiency virus type-1 (HIV-1) integrase enzyme has recently emerged as a primary alternative target to block viral replication, and integrase strand transfer inhibitors (INSTIs) are now considered an alternative 'third agent' class of antiretroviral (ARV) drugs. Dolutegravir is the first next-generation INSTI showing some novel and intriguing characteristics: it has a favorable pharmacokinetic profile with a prolonged intracellular halflife, rendering feasible a once daily dosing without the need for pharmacokinetic boosting. Secondly, it is largely metabolized via uridine diphosphate glucuronosyltransferase-1A1 with a minor component of cytochrome P450 isoforms, thus allowing a low grade of drug-drug interactions, so that its metabolic profile consents coadministration with the majority of the other ARV drugs without dose adjustments. Lastly, but no less important, virological studies have clearly demonstrated that dolutegravir has a significant activity against HIV-1 isolates showing raltegravir and/or elvitegravir associated resistance mutations. The attributes of once daily administration and the potential to treat INSTI-resistant viruses make dolutegravir an interesting and promising new agent in the treatment of both naïve and experienced HIV-1 subjects. In this review, the main concerns on dolutegravir efficacy are focused through the analysis of the currently available data from clinical studies in naïve and experienced patients, evaluating its possible place within the anti-HIV-1 drug armamentarium. The development of newer once daily, single tablet coformulations improved drug adherence and maximized the success of ARV therapy. Pharmacokinetic studies and dose-ranging trials suggested that dolutegravir is a good candidate for a single tablet regimen in one or more new coformulated pills that will be available in the near future.

Background: Persistent residual viremia (RV) and low grade inflammation and immune activation have been associated with non-AIDS defining events. The impact of persistent RV and HIV-DNA load on immune activation/ inflammation remains unclear. The purpose of this study was to gain new insights into the relation between viremia, markers of inflammation and HIV-DNA levels.

HIV-1 infection is associated with increased platelet oxidative stress, which was related to the activation of NOX2. The independent association between platelet NOX2 activation and plasma levels of sCD40L suggest that in vivo platelet activation may be dependent upon platelet oxidative stress.

Impaired haematopoiesis during HIV-1 infection may be caused by the overproduction of inflammatory cytokines by immune cells at the bone marrow level inducing Fas-mediated apoptosis of stem progenitors. In this study, we evaluated the effects of highly active antiretroviral therapy on apoptosis of CD34+ stem cells derived from the bone marrow of HIV-1-infected patients, and observed decreased Fas expression on progenitor cells, in parallel with the diminution of TNF-alpha levels and the amelioration of clonogenic parameters.