The NLRP3 Inflammasome Is Upregulated in HIV-Infected Antiretroviral Therapy-Treated Individuals with Defective Immune Recovery

Background: Inflammasome-mediated activation of caspase-1 regulates inflammatory responses and pyroptosis. We analyzed possible associations between inflammasome-related genes and immune reconstitution in HIV-infected antiretroviral therapy (ART)-treated patients. Methods: Cross-sectional, case-control study. HIV-infected patients on ART for 6524\u2009months with HIV-RNA<50 cp/mL for 6512\u2009months were enrolled and defined as immunological responders (IR) or non-responders (INR) if CD4 count was 65500 or 64350 cells/\u3bcL, respectively. Expression of inflammasome genes, caspases 1, 3, 4, 5 and \u3b3-interferon-inducible protein 16 (IFI16) was measured in unstimulated and LPS- or aldrithiol-2-treated HIV-1BaL virions-stimulated peripheral blood mononuclear cells. Microbial translocation markers were evaluated. Results: Thirty-nine patients (22 IRs; 17 INRs) were enrolled. LPS-stimulated inflammasome genes were significantly upregulated in INRs. Whereas HIV-1BaL stimulation induced (NOD)-like receptor (NLR) family pyrin domain containing 3 (NLRP3) expression in both IRs and INRs, NLRP3 and IL-18 expression was significantly increased in INRs compared to IRs. Significant higher caspase-1 expression was seen as well, whereas caspase 3, 4, and 5 expression was similar in both groups. No differences in microbial translocation markers (LPS and soluble CD14) were detected in the two groups. Conclusion: Upregulation of NLRP3 and caspase-1 is observed in INR patients. This could play a role in persistent immune activation that characterize INRs. Caspase-1 upregulation could induce CD4 T-cell loss via pyroptosis, contributing to unsatisfactory CD4 T-cells recovery

In vivo imaging of immune cell trafficking in cancer

Tumour establishment, progression and regression can be studied in vivo using an array of imaging techniques ranging from MRI to nuclear-based and optical techniques that highlight the intrinsic behaviour of different cell populations in the physiological context. Clinical in vivo imaging techniques and preclinical specific approaches have been used to study, both at the macroscopic and microscopic level, tumour cells, their proliferation, metastasisation, death and interaction with the environment and with the immune system. Fluorescent, radioactive or paramagnetic markers were used in direct protocols to label the specific cell population and reporter genes were used for genetic, indirect labelling protocols to track the fate of a given cell subpopulation in vivo. Different protocols have been proposed to in vivo study the interaction between immune cells and tumours by different imaging techniques (intravital and whole-body imaging). In particular in this review we report several examples dealing with dendritic cells, T lymphocytes and macrophages specifically labelled for different imaging procedures both for the study of their physiological function and in the context of anti-neoplastic immunotherapies in the attempt to exploit imaging-derived information to improve and optimise anti-neoplastic immune-based treatments

The PD-1/PD-L1 pathway in human pathology

T-cell activation is dependent on signals delivered through the antigen-specific T-cell receptor and accessory receptors on T-cells. Integration of signals through this family of costimulatory and inhibitory receptors and their ligands regulates the balance between T-cell activation, tolerance, and immunopathology. Programmed death 1 (PD-1) and its ligands, PD-L1 and PD-L2, deliver inhibitory signals and exert a vital and diverse range of immunoregulatory roles in T-cell activation, tolerance, and immune-mediated tissue damage. In this review, we revisit current understanding of the immunoregulatory functions of PD-1 and its ligands and their involvement in immune-mediated diseases

Immunomodulating activity of Pidotimod in children with Down syndrome

Acute respiratory tract infections (ARTIs) are the most frequent illnesses in pediatric age, frequently experienced in children with Down Syndrome (DS) due to the associated immune defects of both specific and non-specific immunity. Pidotimod, a synthetic immunostimulant, was shown to reduce the rates of ARTIs in children with DS, however the mechanisms associated with this effect is currently unknown. We analyzed immune parameters in DS children who received the seasonal 2011 2012 virosomal-adjuvanted influenza vaccine. Eighteen children aged 3-10 years (mean age 7.1+/-2.6 years) were randomly assigned (1:1 ratio) to receive Pidotimod 400 mg, administered orally once a day for 90 days or placebo. At the recruitment (T0) all children received a single dose of virosomal-adjuvanted influenza vaccine (Flu). Blood samples were collected at T0 and 3 months after the recruitment (T3) in order to evaluate innate and adaptative immune responses pathway. Flu-specific IgG1 and IgG3 levels in plasma samples were determined at pre-vaccination (T0), and 1 (T1) and 3 months (T3) post-vaccination. The use of Pidotimod was associated with the upregulation of a number of genes involved in the activation of innate immune responses and in antimicrobial activity. Interestingly the ratio of Flu-specific IgG1/IgG3 was skewed in pidotimod-treated individuals, suggesting a preferential activation of complement-dependent effector mechanisms. Although preliminary these data suggest that Pidotimod can potentiate the beneficial effect of immunization, possibly resulting in a stronger activity of both innate and adaptive immune responses

Low interleukin-10 production is associated with diabetes in HIV-infected patients undergoing antiviral therapy

Reduced interleukin-10 (IL-10) production is associated with type 2 diabetes in elderly individuals. Antiviral therapy (ARV)-induced immune modulation results in diminished IL-10 production, and diabetes can be observed in ARV-treated human immunodeficiency virus (HIV)-infected individuals. We analyzed, in a cross-sectional pilot study, HIV-antigen-stimulated IL-10 and tumor necrosis factor alpha (TNFalpha) production, and intracellular concentration (ICC), as well as B7-H1 expression, a marker preferentially presented by IL-10-producing cells, in 20 ARV-treated individuals in whom diabetes did (n=10; diabetes mellitus, DM) or did not (n=10; controls) develop. Pre-ARV glucose, cholesterol, and triglycerides levels, duration of HIV infection and of therapy, exposure to protease inhibitors (PI), HIV plasma viremia, CD4 counts, and nadir were similar in DM and control patients. Results showed that: (1) IL-10 production was lower; (2) IL-10 ICC was reduced; (3) B7-H1-expressing CD19(+) cells were diminished; and (4) TNFalpha production and ICC by CD4(+) T cells was augmented in DM patients. Development of diabetes in HIV infected, ARV-treated individuals could be a response to therapy. Similar to what is observed in elderly individuals, low IL-10 production is associated with diabetes in antiviral-treated HIV infection. Further studies will be necessary to clarify whether low IL-10 is a risk factor for, or a consequence of, diabetes

CD4+CD25+FoxP3+PD1- regulatory T cells in acute and stable relapsing-remitting multiple sclerosis and their modulation by therapy

The intracellular expression of the programmed death receptor 1 (PD1) identifies a subset of naive T(reg) cells with enhanced suppressive ability; antigen stimulation results in the surface expression of PD1. Because the role of T(reg) impairments in multiple sclerosis (MS) is still contradictory, we analyzed naive PD1- and PD1+ T(reg) cells in peripheral blood and cerebrospinal fluid (CSF) of relapsing-remitting multiple sclerosis (RR-MS) patients and of healthy control subjects. Results showed that 1) CSF PD1- T(reg) cells were significantly augmented in MS patients; 2) PD1- T(reg) cells were significantly increased in the peripheral blood of patients with stable disease (SMS) compared to those with acute (AMS) disease, and in patients responding to glatiramer acetate (COPA) compared to AMS- and COPA-unresponsive patients; and 3) PD1+ T(reg) cells were similar in CSF and peripheral blood of all groups analyzed. PD1- T(reg) cells were not increased in the peripheral blood of interferon-beta (IFNbeta) -responsive patients, but the suppressive ability of T(reg) cells was significantly higher in SMS and in COPA- or IFNbeta-responsive compared to AMS- and COPA-unresponsive individuals. The data herein suggest that PD1- T(reg) cells play a pivotal role in MS and offer a biological explanation for disease relapse and for the mechanism associated with response to COPA and IFNbeta

Polymorphisms of isotypes of citokines : correlation to intrauterine growth restriction and pre-eclampsia

Background: Type-1 to type-2 cytokine shift is expected in normal pregnancy and correlated to a good pregnancy outcome. Recently, DNA polymorphisms of isotypes of citokines have been correlated to the risk of developing Alzheimer disease. Placental pathology leading to intrauterine growth restriction (IUGR) and/or pre-eclampsia (PE) is due to an anomalous materno-fetal immunitary adaptation. We hypothesize that the risk of IUGR and PE are correlated to peculiar citokines polymorphisms. Objective: The aims of this study were: 1) to test the possibility of assessing polymorphisms of isotypes of citokines in complicated pregnancies by studying mononucleated peripheral blood cells (PBMC); 2) to identify and codifying different isotypes of citokines related to IUGR and/or PE. Methods: ten singleton pregnancies complicated by severe IUGR and/or early-onset PE delivered <30 weeks were included in this preliminary analysis. EDTA-treated blood samples (10 ml) and cord blood samples (7 ml) were obtained from each woman. PBMC were obtained by centrifugation. DNA was extracted from PBMCs using the GENTRA kit. The purified DNA was amplified by PCR-SSP methodology using Cytokine Genotyping Tray (One Lambda, Inc., Canoga Park, CA, Usa) which provides sequence-specific oligonucleotides primers for amplification of selected cytokines (TNF\uf061, IFN\uf067, TGF\uf062, IL6, IL10) alleles. Results: Assessment of different isotypes of citokines was possible in all cases and confirmed at the second blind-testing. In all of the tested cytokines a prevalent genomic pattern coding for high or low production was observed (\uf0b370%). Of interest were the findings for IL6 (9/10 high producers), and IL10 (2/10 high producers). Conclusions: 1) polymorphisms of isotypes of IL10, IL6, TNF\uf061, IFN\uf067, TGF\uf062, IL6, and IL10 can be assessed on PBMC-DNA extracted from maternal blood; 2) Significant prevalence of patterns of genomic isotypes coding for high or low production of solubles factors were observed in this first preliminary analysis. Based on these findings, a larger sample is now under investigation including matched controls and newborns data