Dendritic cells (DC) generated after a short-term exposure of monocytes to IFN-a and GM-CSF (IFN-DC) are highly effective in inducing cross-priming of CD8 + T cells against viral antigens. We have investigated the mechanisms responsible for the special attitude of these DC and compared their activity with that of reference DC. Antigen uptake and endosomal processing capabilities were similar for IFN-DC and IL-4-derived DC. Both DC types efficiently cross-presented soluble HCV NS3 protein to the specific CD8 + T cell clone, even though IFN-DC were superior in cross-presenting low amounts of viral antigens. Moreover, when DC were pulsed with inactivated HIV-1 and injected into hu-PBL-SCID mice, the generation of virus-specific CD8 + T cells was markedly higher in animals immunized with IFN-DC than in mice immunized with CD40L-matured IL-4-DC. Of interest, in experiments with purified CD8 + T cells, IFN-DC were superior with respect to CD40L-matured IL-4-DC in inducing in vitro cross-priming of HIV-specific CD8 + T cells. This property correlated with enhanced potential to express the specific subunits of the IL-23 and IL-27 cytokines. These results suggest that IFN-DC are directly licensed for an efficient CD8 + T cell priming by mechanisms likely involving enhanced antigen presentation and special attitude to produce IL-12 family cytokines.

A major challenge of AIDS research is the development of therapeutic vaccine strategies capable of inducing the humoral and cellular arms of the immune responses against HIV-1. In this work, we evaluated the capability of DCs pulsed with aldrithiol-2–inactivated HIV-1 in inducing a protective antiviral human immune response in SCID mice reconstituted with human PBL (hu-PBL-SCID mice). Immunization of hu-PBL-SCID mice with DCs generated after exposure of monocytes to GM-CSF/IFN-α (IFN-DCs) and pulsed with inactivated HIV-1 resulted in a marked induction of human anti–HIV-1 antibodies, which was associated with the detection of anti-HIV neutralizing activity in the serum. This vaccination schedule also promoted the generation of a human CD8+ T cell response against HIV-1, as measured by IFN-γ Elispot analysis. Notably, when the hu-PBL-SCID mice immunized with antigen-pulsed IFN-DCs were infected with HIV-1, inhibition of virus infection was observed as compared with control animals. These results suggest that IFN-DCs pulsed with inactivated HIV-1 can represent a valuable approach of immune intervention in HIV-1–infected patients.

IntroductionHIV infection is characterized by a persistent immune activation associated to a compromised gut barrier immunity and alterations in the profile of the fecal flora linked with the progression of inflammatory symptoms. The effects of high concentration multistrain probiotic (Vivomixx®, Viale del Policlinico 155, Rome, Italy in EU; Visbiome®, Dupont, Madison, Wisconsin in USA) on several aspects of intestinal immunity in ART‐experienced HIV‐1 patients was evaluated.MethodsA sub‐study of a longitudinal pilot study was performed in HIV‐1 patients who received the probiotic supplement twice a day for 6 months (T6). T‐cell activation and CD4+ and CD8+ T‐cell subsets expressing IFNγ (Th1, Tc1) or IL‐17A (Th17, Tc17) were stained by cytoflorimetric analysis. Histological and immunohistochemical analyses were performed on intestinal biopsies while enterocytes apoptosis index was determined by TUNEL assay.ResultsA reduction in the frequencies of CD4+ and CD8+ T‐cell subsets, expressing CD38+, HLA‐DR+, or both, and an increase in the percentage of Th17 cell subsets, especially those with central or effector memory phenotype, was recorded in the peripheral blood and in gut‐associated lymphoid tissue (GALT) after probiotic intervention. Conversely, Tc1 and Tc17 levels remained substantially unchanged at T6, while Th1 cell subsets increase in the GALT. Probiotic supplementation was also associated to a recovery of the integrity of the gut epithelial barrier, a reduction of both intraepithelial lymphocytes density and enterocyte apoptosis and, an improvement of mitochondrial morphology sustained in part by a modulation of heat shock protein 60.ConclusionsThese findings highlight the potential beneficial effects of probiotic supplementation for the reconstitution of physical and immunological integrity of the mucosal intestinal barrier in ART‐treated HIV‐1‐positive patients.

IMPORTANCEConvalescent plasma (CP) has been generally unsuccessful in preventing worsening of respiratory failure or death in hospitalized patients with COVID-19 pneumonia. OBJECTIVE To evaluate the efficacy of CP plus standard therapy (ST) vs ST alone in preventing worsening respiratory failure or death in patients with COVID-19 pneumonia. DESIGN, SETTING, AND PARTICIPANTS This prospective, open-label, randomized clinical trial enrolled (1:1 ratio) hospitalized patients with COVID-19 pneumonia to receive CP plus ST or ST alone between July 15 and December 8, 2020, at 27 clinical sites in Italy. Hospitalized adults with COVID-19 pneumonia and a partial pressure of oxygen-to-fraction of inspired oxygen (PaO 2 /FiO 2 ) ratio between 350 and 200 mm Hg were eligible. INTERVENTIONS Patients in the experimental group received intravenous high-titer CP (Ն1:160, by microneutralization test) plus ST. The volume of infused CP was 200 mL given from 1 to a maximum of 3 infusions. Patients in the control group received ST, represented by remdesivir, glucocorticoids, and low-molecular weight heparin, according to the Agenzia Italiana del Farmaco recommendations. MAIN OUTCOMES AND MEASURESThe primary outcome was a composite of worsening respiratory failure (PaO 2 /FiO 2 ratio <150 mm Hg) or death within 30 days from randomization. RESULTSOf the 487 randomized patients (241 to CP plus ST; 246 to ST alone), 312 (64.1%) were men; the median (IQR) age was 64 (54.0-74.0) years. The modified intention-to-treat population included 473 patients. The primary end point occurred in 59 of 231 patients (25.5%) treated with CP and ST and in 67 of 239 patients (28.0%) who received ST (odds ratio, 0.88; 95% CI, 0.59-1.33; P = .54). Adverse events occurred more frequently in the CP group (12 of 241 [5.0%]) compared with the control group (4 of 246 [1.6%]; P = .04). CONCLUSIONS AND RELEVANCEIn patients with moderate to severe COVID-19 pneumonia, hightiter anti-SARS-CoV-2 CP did not reduce the progression to severe respiratory failure or death within 30 days. (continued) Key Points Question Is convalescent plasma useful in preventing worsening respiratory failure or death in patients with COVID-19 pneumonia? Findings In this randomized clinical trial of 487 patients with COVID-19 pneumonia and a partial pressure of arterial oxygen-to-fraction of inspired oxygen (PaO 2 /FiO 2 ) ratio between 350 and 200 mm Hg at enrollment, the rate of the primary clinical end point (need for mechanical ventilation, defined as PaO 2 /FiO 2 ratio <150 mm Hg, or death) was not significantly different between the convalescent plasma group and the control group. Meaning In this trial, convalescent plasma did not reduce the progression to severe respiratory failure or death within 30 days.

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The virally encoded integrase protein is an essential enzyme in the life cycle of the HIV-1 virus and represents an attractive and validated target in the development of therapeutics against HIV infection. Drugs that selectively inhibit this enzyme, when used in combination with inhibitors of reverse transcriptase and protease, are believed to be highly effective in suppressing the viral replication. Among the HIV-1 integrase inhibitors, the β-diketo acids (DKAs) represent a major lead for anti-HIV-1drug development. In this study, novel bifunctional quinolonyl diketo acid derivatives were designed, synthesized and tested for their inhibitory ability against HIV-1 integrase. The compounds are potent inhibitors of integrase activity. Particularly, derivative 8 is a potent IN inhibitor for both steps of the reaction (3′-processing and strand transfer) and exhibits both high antiviral activity against HIV-1 infected cells and low cytotoxicity. Molecular modeling studies provide a plausible mechanism of action, which is consistent with ligand SARs and enzyme photo-crosslinking experiments.

Chronic myelogenous leukemia (CML) is IntroductionChronic myelogenous leukemia (CML) is a malignant myeloproliferative disease arising from the clonal expansion of a stem cell characterized by the typical Philadelphia (Ph) chromosome cytogenetic abnormality. 1 Ph-positive tumor cells express the bcr/abl oncogene, which encodes a protein with enhanced tyrosine kinase activity involved in maintaining the malignant phenotype. 2 CML is characterized by an initial chronic phase that invariably evolves to an accelerated phase, and then to a fatal blast crisis, as the malignant cells lose their ability to differentiate. 3 A historic advancement in the management of patients with CML has been achieved by the clinical use of interferon-␣ (IFN-␣), which has represented the first-line therapy in patients who are not candidates for allogeneic stem cell transplantation. IFN-␣ induces complete hematologic (60% to 80%) and major cytogenetic (10% to 20%) responses in patients with chronic-phase CML leading to a significant improvement of survival rates. 4,5 Although the search for more effective treatment modalities has recently led to the clinical utilization of imatinib mesylate (formerly STI571), a potent abl tyrosine kinase inhibitor, as a new anti-CML agent, 6 until now IFN-␣ has still an important role in the management of CML patients. 5,7 IFN-␣ is a group of cytokines belonging to the type I IFN family, which are endowed with potent antiviral, antitumor, and immunoregulatory activities. 8,9 In spite of many years of current use of IFN-␣ in patients with CML and other malignancies, the mechanisms of the antitumor action of these cytokines are still a matter of debate. For a long time, it was thought that the direct inhibitory effects on tumor cell growth/functions were the major mechanisms important in the antitumor response in patients. In fact, IFN-␣ can directly inhibit the proliferation of tumor cells in vitro and can exert other direct effects on tumor cells, including the down-regulation of oncogene expression and induction of tumor suppressor genes. 10 In addition to the direct effects on tumor cells, IFN-␣ exerts several effects on host immune cells that may play a more central role in the overall antitumor response. 11-13 Some reports have recently underscored the potential importance of effects of IFN-␣ on the host immune system for the generation of a long-lasting antitumor response in CML patients. In particular, the recent findings of a strong correlation between the clinical response to IFN-␣ therapy and the presence of T cells specific for an epitope targeted by CML-specific T cells, 14,15 20,21 The most commonly used methods for preparing human DCs for clinical studies are based on the generation of immature DCs from monocytes after several days of treatment with interleukin-4 (IL-4) and granulocytemacrophage colony-stimulating factor (GM-CSF) followed by an incubation step with specific maturation factors. 22,23 Recent studies have shown that type I IFNs are a group of cytokines endowed with a marked cap...

The prevalence of tuberculosis among Mozambican HIV-positive patients starting antiretroviral therapy was 10%, with limited rifampicin resistance. Use of combined point-of-care tests increased case finding, with a short time to treatment. Interventions are needed to remove logistical barriers and prevent presentation in very advanced HIV/tuberculosis disease.