Granulocytic myeloid-derived suppressor cells increased in early phases of primary HIV infection depending on TRAIL plasma level

Background It has been demonstrated that Myeloid Derived Suppressor Cells (MDSC) are expanded in HIV-1 infected individuals and correlated with disease progression. The phase of HIV infection during which MDSC expansion occurs, and the mechanisms that regulate this expansion remain to be established. In this study we evaluated the frequency of MDSC in patients during primary HIV infection, and factors involved in MDSC control. Methods Patients with primary (PHI) and chronic (CHI) HIV infection were enrolled. PHI staging was performed according to Fiebig classification, and circulating MDSC frequency and function were evaluated by flow cytometry. Cytokine levels were evaluated by Luminex technology. Results We found that granulocytic MDSC (Gr-MDSC) frequency was higher in PHI compared to healthy donors, but lower than CHI. Interestingly, Gr-MDSC expansion was observed in the early phases of HIV infection (Fiebig II/III), but it was not associated to HIV viral load and CD4 T cell count. Interestingly, in PHI Gr-MDSC frequency was inversely correlated with plasmatic level of TRAIL, while a direct correlation was observed in CHI. Further, lower level of GMCSF was observed in PHI compared with CHI. In vitro experiments demonstrated that, differently from CHI, recombinant TRAIL induced apoptosis of Gr-MDSC from PHI, can effect that can be abrogated by GM-CSF. Conclusion We found that Gr-MDSC are expanded early during primary HIV infection and may be regulated by TRAIL and GM-CSF levels. These findings shed light on the fine mechanisms regulating the immune system during HIV infection, and open new perspectives for immune-based strategies

Neutralizing activity and T Cell response after bivalent fifth dose of mRNA vaccine in person living with HIV

OBJECTIVES: To investigate immunogenicity of SARS-CoV-2 vaccine third booster (3BD; fifth dose) with bivalent vaccine original/BA4/5 vaccine in people living with HIV (PLWH). STUDY DESIGN: This is an observational cohort study to evaluate the outcomes of SARS-CoV-2 vaccination (HIV-VAC study). We analyzed microneutralization assay and IFN-γ production in 48 PLWH on ART with CD4 count <200 cell/mm3 and/or previous AIDS according to immunization status: vaccinated PLWH who had a previous SARS-CoV-2 infection (hybrid immunization, HI) vs. those only vaccinated (non-hybrid immunization, nHI) and current CD4 count RESULTS: After 15 days from its administration (T1), the 3BD bivalent mRNA vaccine elicited a statistically significant increase of neutralizing antibodies (nAbs) geometric mean titers (GMTs) from T0 to T1 against W-D614G (fold-increase 4.8; p<0.0001), BA.5 (8.6 p<0.0001), BQ.1.1 (6.4, p<0.0001) and XBB.1 (6.5, p<0.0001). When compared to BA.5, nAbs GMTs against BQ.1.1 and XBB.1 decreased by 3.5 and 4.1-fold, respectively. After controlling for age, years from AIDS diagnosis, CD4 count at administration and CD4 count nadir, the fold change reduction in nAbs response to other VoCs as compared to BA.1, was larger in participants with HI vs. those nHI: 0.59 lower (95%CI 0.36, 0.97, p=0.04) for BQ.1.1 and 0.67 lower (95% CI: 0.47, 0.96, p=0.03) for XBB.1.In contrast, the analysis carried little evidence for an association between current CD4 count and response to the fifth dose of bivalent vaccine. Furthermore, cell-mediated immunity remained stable. CONCLUSIONS: Our data support the current recommendation of offering bivalent mRNA vaccine booster doses to PLWH with low CD4 count or previous AIDS at first vaccination, especially in those who never previously acquired SARS CoV2 and regardless of current CD4 count

PMN-MDSC frequency discriminates active versus latent tuberculosis and could play a role in counteracting the immune-mediated lung damage in active disease

: Tuberculosis (TB), due to Mycobacterium tuberculosis infection, is still the principal cause of death caused by a single infectious agent. The balance between the bacillus and host defense mechanisms reflects the different manifestations of the pathology. Factors defining this variety are unclear and likely involve both mycobacterial and immunological components. Myeloid derived suppressor cells (MDSC) have been shown to be expanded during TB, but their role in human TB pathogenesis is not clear. We evaluated the frequency of circulating MDSC by flow-cytometry in 19 patients with active TB, 18 with latent TB infection (LTBI), and 12 healthy donors (HD) as control. Moreover, we investigated the capacity of MDSC to modulate the mycobactericidal activity of monocytes. The association between MDSC level and TB chest X-ray severity score was analyzed. We observed that, unlike active TB, polymorphonuclear (PMN)-MDSC are not expanded in LTBI patients, and, by performing a receiver operating characteristic (ROC) curve analysis, we found that PMN-MDSC frequency supported the discrimination between active disease and LTBI. Interestingly, we observed an association between PMN-MDSC levels and the severity of TB disease evaluated by chest X-ray. Specifically, PMN-MDSC frequency was higher in those classified with a low/mild severity score compared to those classified with a high severity score. Moreover, PMN-MDSC can impact mycobacterial growth by inducing ROS production in Bacillus Calmette et Guerin (BCG)-infected monocytes. This effect was lost when tested with M. tuberculosis (MTB), In conclusion, our data indicate that the elevated frequency of PMN-MDSC in IGRA-positive individuals is associated with active TB. Our findings also pointed out a beneficial role of PMN-MDSC during human active TB, most likely associated with the limitation of inflammation-induced tissue damage

Upscaling of Electrospinning Technology and the Application of Functionalized PVDF-HFP@TiO2 Electrospun Nanofibers for the Rapid Photocatalytic Deactivation of Bacteria on Advanced Face Masks

In recent years, Electrospinning (ES) has been revealed to be a straightforward and innovative approach to manufacture functionalized nanofiber-based membranes with high filtering performance against fine Particulate Matter (PM) and proper bioactive properties. These qualities are useful for tackling current issues from bacterial contamination on Personal Protective Equipment (PPE) surfaces to the reusability of both disposable single-use face masks and respirator filters. Despite the fact that the conventional ES process can be upscaled to promote a high-rate nanofiber production, the number of research works on the design of hybrid materials embedded in electrospun membranes for face mask application is still low and has mainly been carried out at the laboratory scale. In this work, a multi-needle ES was employed in a continuous processing for the manufacturing of both pristine Poly (Vinylidene Fluoride-co-Hexafluoropropylene) (PVDF-HFP) nanofibers and functionalized membrane ones embedded with TiO2 Nanoparticles (NPs) (PVDF-HFP@TiO2). The nanofibers were collected on Polyethylene Terephthalate (PET) nonwoven spunbond fabric and characterized by using Scanning Electron Microscopy and Energy Dispersive X-ray (SEM-EDX), Raman spectroscopy, and Atomic Force Microscopy (AFM) analysis. The photocatalytic study performed on the electrospun membranes proved that the PVDF-HFP@TiO2 nanofibers provide a significant antibacterial activity for both Staphylococcus aureus (~94%) and Pseudomonas aeruginosa (~85%), after only 5 min of exposure to a UV-A light source. In addition, the PVDF-HFP@TiO2 nanofibers exhibit high filtration efficiency against submicron particles (~99%) and a low pressure drop (~3 mbar), in accordance with the standard required for Filtering Face Piece masks (FFPs). Therefore, these results aim to provide a real perspective on producing electrospun polymer-based nanotextiles with self-sterilizing properties for the implementation of advanced face masks on a large scale

Predicting respiratory failure in patients infected by SARS-CoV-2 by admission sex-specific biomarkers

Background: Several biomarkers have been identified to predict the outcome of COVID-19 severity, but few data are available regarding sex differences in their predictive role. Aim of this study was to identify sex-specific biomarkers of severity and progression of acute respiratory distress syndrome (ARDS) in COVID-19. Methods: Plasma levels of sex hormones (testosterone and 17β-estradiol), sex-hormone dependent circulating molecules (ACE2 and Angiotensin1-7) and other known biomarkers for COVID-19 severity were measured in male and female COVID-19 patients at admission to hospital. The association of plasma biomarker levels with ARDS severity at admission and with the occurrence of respiratory deterioration during hospitalization was analysed in aggregated and sex disaggregated form. Results: Our data show that some biomarkers could be predictive both for males and female patients and others only for one sex. Angiotensin1-7 plasma levels and neutrophil count predicted the outcome of ARDS only in females, whereas testosterone plasma levels and lymphocytes counts only in males. Conclusions: Sex is a biological variable affecting the choice of the correct biomarker that might predict worsening of COVID-19 to severe respiratory failure. The definition of sex specific biomarkers can be useful to alert patients to be safely discharged versus those who need respiratory monitoring

Humoral and cellular immune response elicited by mRNA vaccination against SARS-CoV-2 in people living with HIV (PLWH) receiving antiretroviral therapy (ART) according with current CD4 T-lymphocyte count

BACKGROUND: Data on SARS-CoV-2 vaccine immunogenicity in PLWH are currently limited. Aim of the study was to investigate immunogenicity according to current CD4 T-cell count. METHODS: PLWH on ART attending a SARS-CoV-2 vaccination program, were included in a prospective immunogenicity evaluation after receiving BNT162b2 or mRNA-1273. Participants were stratified by current CD4 T-cell count (poor CD4 recovery, PCDR: 500/mm^{3}). RBD-binding IgG, SARS-CoV-2 neutralizing antibodies (nAbs) and IFN-γ release were measured. As control group, HIV-negative healthcare workers (HCWs) were used. FINDINGS: Among 166 PLWH after 1 month from the second dose, detectable RBD-binding IgG were elicited in 86.7% of PCDR, 100% of ICDR, 98.7% of HCDR, and a neutralizing titre ≥1:10 elicited in 70.0%, 88.2% and 93.1%, respectively. Compared to HCDR, all immune response parameters were significantly lower in PCDR. After adjusting for confounders, current CD4 T-cell 500 cell/mm^{3} and HIV-negative controls. A decreased RBD-binding antibody response than HCWs was also observed in PLWH with CD4 T-cell 200-500/mm^{3}, whereas immune response elicited in PLWH with a CD4 T-cell >500/mm^{}3 was comparable to HIV-negative population

Interferon-α Improves Phosphoantigen-Induced Vγ9Vδ2 T-Cells Interferon-γ Production during Chronic HCV Infection

In chronic HCV infection, treatment failure and defective host immune response highly demand improved therapy strategies. Vγ9Vδ2 T-cells may inhibit HCV replication in vitro through IFN-γ release after Phosphoantigen (PhAg) stimulation. The aim of our work was to analyze Vγ9Vδ2 T-cell functionality during chronic HCV infection, studying the role of IFN-α on their function capability. IFN-γ production by Vγ9Vδ2 T-cells was analyzed in vitro in 24 HCV-infected patients and 35 healthy donors (HD) after PhAg stimulation with or without IFN-α. The effect of in vivo PhAg/IFN-α administration on plasma IFN-γ levels was analyzed in M. fascicularis monkeys. A quantitative analysis of IFN-γ mRNA level and stability in Vγ9Vδ2 T-cells was also evaluated. During chronic HCV infection, Vγ9Vδ2 T-cells showed an effector/activated phenotype and were significantly impaired in IFN-γ production. Interestingly, IFN-α was able to improve their IFN-γ response to PhAg both in vitro in HD and HCV-infected patients, and in vivo in Macaca fascicularis primates. Finally, IFN-α increased IFN-γ-mRNA transcription and stability in PhAg-activated Vγ9Vδ2 T-cells. Altogether our results show a functional impairment of Vγ9Vδ2 T-cells during chronic HCV infection that can be partially restored by using IFN-α. A study aimed to evaluate the antiviral impact of PhAg/IFN-α combination may provide new insight in designing possible combined strategies to improve HCV infection treatment outcome

Serum Albumin Is Inversely Associated With Portal Vein Thrombosis in Cirrhosis

We analyzed whether serum albumin is independently associated with portal vein thrombosis (PVT) in liver cirrhosis (LC) and if a biologic plausibility exists. This study was divided into three parts. In part 1 (retrospective analysis), 753 consecutive patients with LC with ultrasound-detected PVT were retrospectively analyzed. In part 2, 112 patients with LC and 56 matched controls were entered in the cross-sectional study. In part 3, 5 patients with cirrhosis were entered in the in vivo study and 4 healthy subjects (HSs) were entered in the in vitro study to explore if albumin may affect platelet activation by modulating oxidative stress. In the 753 patients with LC, the prevalence of PVT was 16.7%; logistic analysis showed that only age (odds ratio [OR], 1.024; P = 0.012) and serum albumin (OR, -0.422; P = 0.0001) significantly predicted patients with PVT. Analyzing the 112 patients with LC and controls, soluble clusters of differentiation (CD)40-ligand (P = 0.0238), soluble Nox2-derived peptide (sNox2-dp; P &lt; 0.0001), and urinary excretion of isoprostanes (P = 0.0078) were higher in patients with LC. In LC, albumin was correlated with sCD4OL (Spearman's rank correlation coefficient [r(s)], -0.33; P &lt; 0.001), sNox2-dp (r(s), -0.57; P &lt; 0.0001), and urinary excretion of isoprostanes (r(s), -0.48; P &lt; 0.0001) levels. The in vivo study showed a progressive decrease in platelet aggregation, sNox2-dp, and urinary 8-iso prostaglandin F2 alpha-III formation 2 hours and 3 days after albumin infusion. Finally, platelet aggregation, sNox2-dp, and isoprostane formation significantly decreased in platelets from HSs incubated with scalar concentrations of albumin. Conclusion: Low serum albumin in LC is associated with PVT, suggesting that albumin could be a modulator of the hemostatic system through interference with mechanisms regulating platelet activation

Neutralizing antibodies to Omicron after the fourth SARS-CoV-2 mRNA vaccine dose in immunocompromised patients highlight the need of additional boosters

IntroductionImmunocompromised patients have been shown to have an impaired immune response to COVID-19 vaccines.MethodsHere we compared the B-cell, T-cell and neutralizing antibody response to WT and Omicron BA.2 SARS-CoV-2 virus after the fourth dose of mRNA COVID-19 vaccines in patients with hematological malignancies (HM, n=71), solid tumors (ST, n=39) and immune-rheumatological (IR, n=25) diseases. The humoral and T-cell responses to SARS-CoV-2 vaccination were analyzed by quantifying the anti-RBD antibodies, their neutralization activity and the IFN-γ released after spike specific stimulation.ResultsWe show that the T-cell response is similarly boosted by the fourth dose across the different subgroups, while the antibody response is improved only in patients not receiving B-cell targeted therapies, independent on the pathology. However, 9% of patients with anti-RBD antibodies did not have neutralizing antibodies to either virus variants, while an additional 5.7% did not have neutralizing antibodies to Omicron BA.2, making these patients particularly vulnerable to SARS-CoV-2 infection. The increment of neutralizing antibodies was very similar towards Omicron BA.2 and WT virus after the third or fourth dose of vaccine, suggesting that there is no preferential skewing towards either virus variant with the booster dose. The only limited step is the amount of antibodies that are elicited after vaccination, thus increasing the probability of developing neutralizing antibodies to both variants of virus.DiscussionThese data support the recommendation of additional booster doses in frail patients to enhance the development of a B-cell response directed against Omicron and/or to enhance the T-cell response in patients treated with anti-CD20

Analisi della risposta dei linfociti T Vγ9Vδ2 a linee cellulari di glioma umano : possibili implicazioni per la terapia

T cells link innate and acquired immunity. In humans 90% of circulating T cells express the V9V2 TCR rearrangement and recognize non peptidic antigens in a MHC-unrestricted manner. After antigen recognition, activated V9V2 T cells rapidly proliferate, produce high levels of cytokines and chemokines and can differentiate in cytotoxic effector cells. Specifically, V9V2 T cells recognize unprocessed non-peptidic compounds such as isopentenyl pyrophosphate (IPP), which are produced through the isoprenoid biosynthesis pathway. Moreover, V9V2 T cells can also be activated by aminobisphosphonates drugs through an indirect mechanism: they inhibit farnesyl pyrophosphate synthase, an enzyme of cholesterol biosynthesis, acting downstream of IPP synthesis; this inhibition, in turn, leads to the accumulation of endogenous IPP, directly recognized by V9V2 T cells. A specific feature of V2 T cell biology is their ability to recognize tumor cells presenting a dis-regulation in mevalonate pathway, resulting in an increase of phosphorilated metabolites such as isopentenyl-pyrophosphate (IPP). Thus, the increased isoprenoid metabolism in cancer cells induces V2 T cell activation through cellular IPP accumulation. Mevalonate cycle is present in all eucaryotic cells and produce cholesterol and prenyl-compounds. The main two enzymes (HMG-CoA reductase and FPP synthase) in the mevalonate pathway are carefully regulated and can be farmacologically modulated by different drugs (mevastatin and aminobisphosphonates respectively). Several studies show that V2 T cells recognize and kill several cancer cells, such as lymphoma, colon-, lung-, renal, breast carcinoma, and glioma. In renal cancer patients, a V2- based immunotherapy with a synthetic phosphorilated compound is in course with promising results. Similarly, aminobisphosphonates (Zoledronic Acid) is currently used for bone metastases in prostate cancer patients. In this context, the possibility to massively activate and expand in vitro a relatively large number of cells opens new interesting prospects in the immunotherapy of cancer disease. Gliomas are tumors arising from glia or their precursors within the central nervous system. Unfortunately, the majority of patients with glioma tumors die in less then of one year; in these patients, new treatment strategies are therefore hardly needed. Aim of this study was to analyse the activity of human V2 T cells against glioma cancer cells and to verify the possibility to target these innate cells in new immunotherapeutical strategies. In a first set of experiments, we set up an in vitro protocol able to expand human V2 T cells by using IPP and IL-2. After 12 days the expanded V2 T cell lines (80-95% of purity) were analysed for their differentiation phenotype, (as expression of CD27 and CD45RA markers of T, B, NK cells), cytokines production (IFN and TNF) and natural cytotoxicity capability (Perforin). Results showed that in vitro expanded V2 T cell lines present an effector memory phenotype and have high functionality both in terms of cytokines production and Perforin release. We then studied three different glioma cell lines: T70, U373 and U251 by analyzing GFAP expression on cell surface by direct immunofluorescence. Resulted showed that all glioma cells was positive for GFAP. In a second set of experiments, V2 T cell lines were co-cultured with glioma cells in order to analyse the activation of V2 T cells and the effects on the viability of glioma cells. In our system, V2 T cell lines were able to recognized glioma cells (T70, U373, U251) by specifically differentiate in effector memory cells, and release Perforin. In contrast, they did not produce cytokines. In order to verify the cytotoxic effect of V2 T cells on glioma cells, we performed a viability test on glioma cells in the absence and in the presence of V2 T cell lines. Briefly, glioma cells were labelled with Annexin/Propidium Iodide and were analysed by flow cytometry. Interestingly, V2 T cells were able to kill glioma cells through an apoptotic mechanism, demonstrating their antitumoral activity. We then decided to study if Zoledronic Acid (ZOL) treatment of glioma cells could improve V2 T lines response. Glioma cells were treated with ZOL in vitro for two hours, and co-cultured with V2 T cell lines, analyzing V2 T cells response by flow cytometry. Results showed that V2 T cell lines were able to recognize glioma cells by releasing high amount of IFN and TNF. V2 T cells activation was mediated by ZOL-induced IPP accumulation, since the incubation with mevastatin was able to completely block this biological effect. Finally, we studied the direct effect of different concentrations of ZOL on glioma cells viability before and after the co-culture with V2 T lines. We observed that treatment with ZOL induced necrosis on glioma cells, but only the co-culture with V2 T lines together to the treatment with ZOL increased both the apoptosis and necrosis of glioma cells. Altogether, our results suggest that the induction of a strong antitumoral response of V2 T cells by using aminobisphosphonates could represent a new interesting immunotherapy approach for glioma care