Neurocognitive Impairment in HIV-Infected Naïve Patients with Advanced Disease: The Role of Virus and Intrathecal Immune Activation

Objective. To investigate intrathecal immune activation parameters and HIV-RNA in HIV-associated neurocognitive disorders (HAND) of advanced naïve HIV-infected patients and to evaluate their dynamics before and after initiation of antiretroviral therapy (ART). Methods. Cross-sectional and longitudinal analysis of HIV RNA, proinflammatory cytokines (IL-6, IL-10, INF-γ, TNF-α, TGF-β1, and TGF-β2) and chemokines (MIP-1α, MIP-1β, and MCP-1) in plasma and cerebrospinal fluid (CSF) of HIV-infected patients with CD4 <200/μL. Results. HAND was diagnosed at baseline in 6/12 patients. Baseline CSF HIV-RNA was comparable in patients with or without HAND, whereas CSF concentration of IL-6 and MIP-1β, proinflammatory cytokines, was increased in HAND patients. CSF evaluation at 12 weeks was available in 10/12 cases. ART greatly reduced HIV-RNA in all patients. Nevertheless, IL-6 and MIP-1β remained elevated after 12 weeks of therapy in HAND patients, in whom CSF HIV RNA decay was slower than the plasmatic one as well. Conclusion. Immune activation, as indicated by inflammatory cytokines, but not higher levels of HIV-RNA is observed in advanced naïve HIV-infected patients with HAND. In HAND patients, ART introduction resulted in a less rapid clearance of CSF viremia compared to plasma and no modifications of intratechal immune activation

CCL28 Induces Mucosal Homing of HIV-1-Specific IgA-Secreting Plasma Cells in Mice Immunized with HIV-1 Virus-Like Particles

Mucosae-associated epithelial chemokine (MEC or CCL28) binds to CCR3 and CCR10 and recruits IgA-secreting plasma cells (IgA-ASCs) in the mucosal lamina propria. The ability of this chemokine to enhance migration of IgA-ASCs to mucosal sites was assessed in a mouse immunization model using HIV-1IIIB Virus-like particles (VLPs). Mice receiving either HIV-1IIIB VLPs alone, CCL28 alone, or the irrelevant CCL19 chemokine were used as controls. Results showed a significantly increased CCR3 and CCR10 expression on CD19+ splenocytes of HIV-1IIIB VPL-CCL28-treated mice. HIV-1 Env-specific IFN-γ, IL-4 and IL-5 production, total IgA, anti-Env IgA as well as gastro-intestinal mucosal IgA-secreting plasma cells were also significantly augmented in these mice. Notably, sera and vaginal secretions from HIV-1IIIB VLP-CCL28-treated mice exhibited an enhanced neutralizing activity against both a HIV-1/B-subtype laboratory strain and a heterologous HIV-1/C-subtype primary isolate. These data suggest that CCL28 could be useful in enhancing the IgA immune response that will likely play a pivotal role in prophylactic HIV vaccines

Prospective Immune Dynamics during the First 24 Weeks of Efavirenz Based-Antiretroviral Therapy in HIV-1-Infected Subjects, According to CD4⁺ T-Cell Counts at Presentation: The IMMUNEF Clinical Trial

<div><p>Background</p><p>Longitudinal characterization of immune recovery in the first-phase of antiretroviral therapy (ART) is poorly described. We compared immune kinetics in individuals who were diagnosed early or late with HIV-1 infection, (thus commencing ART with different CD4⁺ T-cell counts), in order to investigate possible mechanisms involved in subsequent poor immune recovery.</p><p>Methods</p><p>Immunophenotyping, immune activation, proliferation, apoptosis, regulatory T-cells and intracellular cytokine production were compared at baseline and during 24-week follow-up in two groups of HIV-1-infected patients initiating the same ART (tenofovir/emtricitabine/efavirenz) and divided according to baseline CD4⁺ T-cell counts (late: ≤200/μL; early: >200/μL). Wilcoxon-rank sum test and analysis for repeated measures were used to evaluate differences between groups over time.</p><p>Results</p><p>Twenty-four out of 30 enrolled subjects were evaluable for the analysis, 13 late and 11 early presenters. Significantly lower CD4⁺ naïve and memory T-cells, and higher plasma viral load, as well as augmented percentages of activated (CD4⁺/CD25⁺ cells), apoptotic (CD4⁺/AnnexinV⁺/7AAD⁻, CD4⁺/caspase 8⁺ and CD4⁺/caspase 9⁺), and proliferating (CD8⁺/Ki67⁺ cells) lymphocytes were present at baseline in late presenters; ART resulted in a reduction of apoptotic and proliferating lymphocytes within the follow-up period.</p><p>Conclusions</p><p>A skewing towards memory/activated/apoptotic phenotype is seen in HIV-1-infected subjects starting ART at low CD4⁺ T-cell counts; ART results in early (24 weeks) trend towards normalization of these parameters. Antiretroviral therapy may play a role in rapidly limiting aberrant immune exhaustion even in late presenters, while requiring more time for re-population of highly depleted naïve T-cells.</p><p>Trial Registration</p><p>EU Clinical Trial Register EUDRACT number 2008-006188-35 <a href="https://www.clinicaltrialsregister.eu/ctr-search/trial/2008-006188-35/IT" target="_blank">https://www.clinicaltrialsregister.eu/ctr-search/trial/2008-006188-35/IT</a></p></div

Correction: Immunological Characterization of Whole Tumour Lysate-Loaded Dendritic Cells for Cancer Immunotherapy.

INTRODUCTION:Dendritic cells play a key role as initiators of T-cell responses, and even if tumour antigen-loaded dendritic cells can induce anti-tumour responses, their efficacy has been questioned, suggesting a need to enhance immunization strategies. MATHERIALS & METHODS:We focused on the characterization of bone marrow-derived dendritic cells pulsed with whole tumour lysate (TAA-DC), as a source of known and unknown antigens, in a mouse model of breast cancer (MMTV-Ras). Dendritic cells were evaluated for antigen uptake and for the expression of MHC class I/II and costimulatory molecules and markers associated with maturation. RESULTS:Results showed that antigen-loaded dendritic cells are characterized by a phenotypically semi-mature/mature profile and by the upregulation of genes involved in antigen presentation and T-cell priming. Activated dendritic cells stimulated T-cell proliferation and induced the production of high concentrations of IL-12p70 and IFN-γ but only low levels of IL-10, indicating their ability to elicit a TH1-immune response. Furthermore, administration of Antigen loaded-Dendritic Cells in MMTV-Ras mice evoked a strong anti-tumour response in vivo as demonstrated by a general activation of immunocompetent cells and the release of TH1 cytokines. CONCLUSION:Data herein could be useful in the design of antitumoral DC-based therapies, showing a specific activation of immune system against breast cancer

Polarization of CD3⁺ lymphocytes by whole tumour-lysate pulsed DCs.

<p>To examine the nature of T-cell responses induced by whole tumour-lysate pulsed DCs, syngeneic naïve T-cells from MMTV-<i>Ras</i> mice were cultured with either unloaded DCs or TAA-DCs for 1-3-5-7- days and both T cell- and DC-derived cytokines were measured. ELISA quantified released type 1 [IFN-γ (A), IL-12 (C)] and type 2 [IL-10 (B)] cytokines in the supernatants. Results are expressed as mean values ± standard error of three independent experiments. *P value < 0.05; **P value <0.005.</p

CFSE assay for assessment of T-cell function.

<p>The 7 day response of CFSE-labelled syngeneic T-cells from the spleen of MMTV-<i>Ras</i> mice to stimulation with tumour lysate-pulsed DCs. CD3/CFSE dot plot (A) and CFSE histogram (B and C, anti-CD3 activated T cells and unstimulated T-cells, respectively) are shown. All plots were gated on CD3-positive cells, while the histograms were also gated to include both resting lymphocytes and blasts. (A): alterations in light scatter characteristics; (B and C): progressive two-fold dilutions of CFSE that accompanied mitotic cell division (gate D1). Both anti-CD3 activated and unstimulated T-cells were incubated with tumour lysate pulsed-DCs, unpulsed DC (negative control) and LPS-stimulated DCs (positive control). Application of an analysis algorithm (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0146622#sec006" target="_blank">Materials and Methods</a>) resulted in a proliferation index of 2,93. One representative of three independent experiments is shown.</p