Heme Oxygenase-1/High Mobility Group Box 1 Pathway May Have a Possible Role in COVID-19 ARDS (Acute Respiratory Distress Syndrome): A Pilot Histological Study.

COVID-19 is a pandemic disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The persistent and excessive inflammatory response can build up a clinical picture that is difficult to manage and potentially fatal. Potent activators of inflammatory phenomena are damage-associated molecular patterns (DAMPs) and, in particular, the high-mobility group box 1 (HMGB1). HMGB1 is an intranuclear protein that is either passively released during hypoxia-related necrosis or actively released by macrophages. Heme oxygenase (HO-1) has an anti-inflammatory effect by inhibiting HMGB1, which could be a therapeutic target to reduce COVID-19 inflammation. In our study, we evaluated CD3, CD4, CD8, HMGB1 and HO-1 in the COVID-19 lung and correlated it to clinical data.

Ageing and inflammation in patients with HIV infection.

Nowadays, HIV+ patients have an expected lifespan that is only slightly shorter than healthy individuals. For this reason, along with the fact that infection can be acquired at a relatively advanced age, the effects of ageing on HIV+ people have begun to be evident. Successful anti-viral treatment is, on one hand, responsible for the development of side effects related to drug toxicity; on the other hand, it is not able to inhibit the onset of several complications caused by persistent immune activation and chronic inflammation. Therefore, patients with a relatively advanced age, i.e. aged more than 50 years, can experience pathologies that affect much older citizens. HIV+ individuals with non-AIDS-related complications can thus come to the attention of clinicians because of the presence of neurocognitive disorders, cardiovascular diseases, metabolic syndrome, bone abnormalities and non-HIV-associated cancers. Chronic inflammation and immune activation, observed typically in elderly people and defined as 'inflammaging', can be present in HIV+ patients who experience a type of premature ageing, which affects the quality of life significantly. This relatively new condition is extremely complex, and important factors have been identified as well as the traditional behavioural risk factors, e.g. the toxicity of anti-retroviral treatments and the above-mentioned chronic inflammation leading to a functional decline and a vulnerability to injury or pathologies. Here, we discuss the role of inflammation and immune activation on the most important non-AIDS-related complications of chronic HIV infection, and the contribution of aging per se to this scenario.

p-Cresol and Cardiovascular Risk in Kidney Transplant Recipients.

p-Cresol Sulphate (pCS) is a uremic toxin that originates exclusively from dietary sources and has a high plasma level related to chronic kidney disease (CKD) and cardiovascular disease (CVD). The aim of our study was to evaluate the plasma levels of pCS in kidney transplant recipients (KTRs) related to estimated glomerular filtration rate (eGFR), traditional risk factors, cardiovascular clinical events and endothelial progenitor cells (EPCs), bone marrow-derived cells for the vascular repair system. We considered 51 KTRs and 25 healthy blood donors (HBDs). pCs levels were analyzed using high-performance liquid chromatography (HPLC) coupled with mass spectrometry with an electrospray ionization (ESI) (LC/ESI-MS/MS) on a triple-quadrupole; EPCs were analyzed using flow cytometric analysis. eGFR was 52.61 ± 19.9 mL/min/1.73 m(2) in KTRs versus 94 ± 21 mL/min/1.73 m(2) in HBDs. We did not find differences in pCS levels between KTRs and HBDs. Levels of pCS were inversely related with eGFR in KTRs and pCS levels were significantly lower in KTRs with eGFR <30 mL/min/1.73 m(2) versus eGFR >30 mL/min/1.73 m(2). Furthermore, there was a difference in pCS levels between eGFR <30 mL/min/1.73 m(2) of KTRs compared with HBDs. Levels of pCS were almost significantly influenced by the presence of a previous vascular event and were inversely related with mature EPCs. These findings suggest that KTRs should not have higher CVD risk than HBDs and their physiological vascular repair system appears to be intact. In KTRs the reduction of eGFR also increased pCS levels and reduced EPCs numbers and angiogenesis capacity. In summary, pCS acts as an emerging marker of a uremic state, helping assess the global vascular competence in KTRs.

Dynamics of adaptive and innate immunity in patients treated during primary human immunodeficiency virus infection: results from Maraviroc in HIV Acute Infection (MAIN) randomized clinical trial.

We evaluated the dynamics of innate and adaptive immunity in patients treated with combined antiretroviral therapy (cART) during primary human immunodeficiency virus infection (PHI), enrolled in a prospective randomized trial (MAIN, EUDRACT 2008-007004-29). After 48 weeks of cART, we documented a reduction in activated B cells and CD8(+) T cells. Natural killer cell and dendritic cell frequencies were measured and a decrease in CD16(+) CD56(dim) with a reciprocal rise in CD56(high) natural killer cells and an increase in myeloid and plasmacytoid dendritic cells were recorded. In conclusion, 48 weeks of cART during PHI showed significant benefits for both innate and adaptive immunity.

Randomized trial to evaluate cardiometabolic and endothelial function in patients with plasma HIV-1 RNA suppression switching to darunavir/ritonavir with or without nucleoside analogues.

BACKGROUND: We performed a study to evaluate change in cardiometabolic and endothelial function in HIV-infected patients switching to darunavir/ritonavir (DRV/r) monotherapy versus triple therapy. METHODS: The MONARCH trial recruited 30 patients who were taking triple combination therapy and with HIV RNA<40 copies/ mL. Patients were randomized to either DRV/r 800/100 mg once daily (OD) monotherapy or DRV/r 800/100 mg OD plus 2 nucleoside reverse transcriptase inhibitors (NRTIs). The primary objective was to assess endothelial function change from baseline to 24 and 48 weeks in brachial artery flow-mediated dilation (FMD) test; changes in endothelial precursor cells (EPCs) and circulating endothelial cells (CECs) were secondary objectives. RESULTS: At baseline, the median age of participants was 43 years, 77% were men, and median CD4 cell count was 585 cells/µL. The median FMD (%) decreased in both arms in the study period (P ≯ .05), with no statistically significant difference between arms (10.7% at baseline and 6.7% at week 48 in the DRV/r + 2 NRTIs arm; 11.1% at baseline and 8.8% at week 48 in the DRV/r arm). The changes at week 48 were similar in the 2 arms for EPCs and CECs. Total cholesterol and low-density lipoprotein (LDL) cholesterol showed larger rises to week 48 in the DRV/r arm monotherapy group than in the triple-therapy group (+26 vs +9 mg/dL for total cholesterol and +14 vs +5 mg/dL for LDL cholesterol). CONCLUSIONS: In the MONARCH trial, switching from triple combination treatment to DRV/r, with or without nucleoside analogues, did not translate into clinically meaningful reductions in endothelial function as measured by FMD.

Absence of liver steatosis in HIV-HCV co-infected patients receiving regimens containing tenofovir or abacavir.

BACKGROUND: In human immunodeficiency virus-hepatitis C virus (HIV-HCV) co-infected patients, steatosis has been independently associated with a number of antiretroviral drugs, including stavudine, especially in patients with non-3 HCV genotypes. We retrospectively investigated the presence of steatosis among HIV-HCV co-infected and HCV mono-infected patients, and the role of tenofovir disoproxil fumarate (TDF) or abacavir (ABC) in determining hepatic steatosis. METHODS: Liver steatosis was retrospectively evaluated in all consecutive biopsies performed in the period 2000-2008 in HCV mono-infected and HIV-HCV co-infected patients. A steatosis rate of >5 % was considered to be significant, and a multivariate logistic analysis was performed to evaluate factors associated with steatosis. RESULTS: In total, 393 HCV-infected patients underwent liver biopsy during the study period, of whom 205 (52.2 %) were co-infected with HIV. A steatosis rate of >5 % was diagnosed in 33.0 % of HCV mono-infected and in 47.8 % of HIV-HCV co-infected patients (P = 0.003). The rate of steatosis was higher in patients resuming antiretroviral therapy (54.7 %) than in naïve patients (33.3 %; P = 0.006). When the overall population was considered, steatosis was associated to HCV genotype 3 [odds ratio (OR) 4.53, 95 % confidence interval (CI) 2.71-7.58; P < 0.001]. In terms of the use of nucleos(t)ide drugs in HIV co-infected patients, multivariate analysis showed that only in patients with HCV genotypes other than genotype 3 was steatosis related to the use of stavudine (OR 5.38, 95 % CI 1.18-24.53; P = 0.03). The use of TDF (OR 1.07, 95 % CI 0.39-2.88; P = 0.898) or ABC (OR 0.592, 95 % CI 0.09-4.07; P = 0.594) was not associated with steatosis. CONCLUSION: In HCV mono-infected and HIV-HCV co-infected patients, steatosis appears to be a virus-mediated effect of HCV genotype 3. In HIV patients infected with HCV genotypes other than genotype 3, the risk of developing steatosis was higher in those patients resuming antiretroviral regimens containing old drugs rather than the new antiretrovirals.

Single-nucleotide polymorphism-defined class I and class III major histocompatibility complex genetic subregions contribute to natural long-term nonprogression in HIV infection.

We performed a genome-wide association study comparing a cohort of 144 human immunodeficiency virus (HIV type 1-infected, untreated white long-term nonprogressors (LTNPs) with a cohort of 605 HIV-1-infected white seroconverters. Forty-seven single-nucleotide polymorphisms (SNPs), located from class I to class III major histocompatibility complex (MHC) subregions, show statistical association (false discovery rate, <0.05) with the LTNP condition, among which 5 reached genome-wide significance after Bonferonni correction. The MHC LTNP-associated SNPs are ordered in ≥4 linkage disequilibrium blocks; interestingly, an MHC class III linkage disequilibrium block (defined by the rs9368699 SNP) seems specific to the LTNP phenotype.

T cell homeostasis in centenarians: from the thymus to the periphery.

The immune system undergoes a process of profound remodelling during aging, referred to as immunosenescence, and characterized by complex modifications of several components. In this review, we discuss recent developments and observations regarding the generation of T cells in the thymus during aging and longevity, and the regulation and maintenance of peripheral blood lymphocytes. The generation of new T cells is indeed crucial to maintain a functional immune system, and is a fundamental step to avoid unsuccessful aging, thus reaching longevity in good health. Mechanisms will be described that are related to the production and maintenance of those lymphocytes defined "recent thymic emigrants", and to the detection of the so called "T cell receptor rearrangement excision circles (TREC)", along with the presence in the periphery of naïve and memory T cells, that can be influenced and regulated by several different mechanisms. Several strategies aimed at improving thymic functionality are currently receiving a growing interest, and some of them are based on molecules that are produced by, and/or act on immune cells. Data on the possible use of these molecules, including cytokines like interleukin (IL)-7, IL-15 and keratinocyte growth factor, to restore thymic function are reviewed and discussed.

Relevance of CD38 expression on CD8 T cells to evaluate antiretroviral therapy response in HIV-1-infected youths.

Surrogate markers for monitoring immuno-virological discordant responders, in addition to plasma viral load and CD4 cells, are still lacking. We assessed the diagnostic utility of CD38 expression on CD8 T cell assay, alone or in association with lymphocyte proliferation to mycotic antigens, in evaluating antiretroviral response. 28 vertically HIV-infected youths, 21 HAART- and seven 2 nucleotide reverse transcriptase inhibitors-treated, were enrolled in a retrospective study. Responders (57.1%) and non-responders (42.9%) to stable antiretroviral therapy for a minimum of 6 months, on the basis of viral load and CD4 T cells, comprehensively evaluated by CD38 expression on CD8 T lymphocytes [measured as CD38 antibody bound per CD8 T cell (CD38 ABC) and %CD38+ of total CD8 T cells (%CD38/CD8)] and lymphocyte proliferation to P. jiroveci, C. albicans, C. neoformans, A. fumigatus at a single time point after treatment, were selected. CD38 expression > or =2401 CD38 ABC and > or =85% CD38/CD8 cut-off points, accurately discriminates responders versus non-responders, both measures resulting in 75.0% (CI 42.8-94.5) sensitivity (identification of non-responder) and 93.8% (CI 69.8-99.8) specificity (identification of responder), when considered as single assays. The association '> or =2401 CD38 ABC or > or =85% CD38/CD8' improved sensitivity to 83.3% (CI 51.6-97.9), while the association '<2401 CD38ABC (or <85% CD38/CD8) and lymphoproliferative response positive to > or =2 tested organisms' improved specificity to 100% (CI 79.4-100). In conclusions, CD38 expression and mycotic antigen-specific T-cell proliferation may be used as additional parameters to existing criteria to evaluate antiretroviral response in immuno-virological discordant patients.

HIV-infected long-term nonprogressors display a unique correlative pattern between the interleukin-7/interleukin-7 receptor circuit and T-cell homeostasis.

BACKGROUND: We hypothesized that there may be a correlation between the interleukin-7 (IL-7)/IL-7 receptor (IL-7R) regulatory system and parameters of T-cell homeostasis in HIV-infected long-term nonprogressors (LTNPs) as compared with patients with disease progression. METHODS: The possibility of a correlation between T-cell homeostatic parameters and IL-7/IL-7R was investigated in 22 LTNPs (CD4 count > or =500 cells/microL for >10 years) vs. HIV-positive patients at different disease stages [12 early: CD4 count > or =400 cells/microL ; 15 late (AIDS-presenters): CD4 count < or =150 cells/microL ]. RESULTS: Compared with early-stage HIV-positive patients, LTNPs displayed a higher circulating IL-7 concentration (P=0.05), which was positively associated with higher IL-7Ralpha expression and a higher T-cell receptor excision circle (TREC) content specifically within CD4 cells (P<0.05). Compared with late-stage disease patients, early-stage disease patients displayed a lower IL-7 concentration (P<0.01) and higher percentages of IL-7Ralpha+ CD4 and CD8 cells (P=0.05). IL-7 was positively correlated with the percentage of TREC+ CD4 cells (P<0.01), which translated into a higher percentage of naïve CD4 cells in early-stage disease patients than in late-stage disease patients; however, the CD4 cells in early-stage disease patients were less enriched in recent thymic emigrants (RTEs) compared with LTNPs (P<0.05). In late-stage AIDS-developing patients, substantially increased IL-7 was correlated with a decreased percentage of IL-7Ralpha+ CD4 cells (P=0.01), which resulted in these patients having a significantly lower percentage of naïve T cells (P<0.01) and a significantly lower content of TREC (P<0.01) than the other patients. CONCLUSIONS: The maintenance of high CD4 cell counts in LTNPs was associated with a specific IL-7/IL-7R pattern characterized by increased IL-7 and highest IL-7Ralpha-expressing CD4 cells relative to other patients. Compared with patients with late-stage disease, LTNPs displayed a phenotypically naïve, less activated CD4 cell pool highly enriched in RTEs, suggesting the existence of a compensatory IL-7-mediated pathway specifically sustaining peripheral CD4 counts.

Polymorphisms of fas gene: relationship with Alzheimer's disease and cognitive decline.

The Fas antigen (CD95) is a cell surface receptor that mediates cell apoptosis signalling. Recent investigations have shown that Fas-regulated apoptosis was linked to neurodegenerative lesions in the brain of patients with Alzheimer's disease (AD). Here data regarding the association of two polymorphisms of the Fas promoter region with AD patient's cognitive deterioration are reported. The polymorphism at position -1377 was associated with the risk of developing AD and with a differential rate of cognitive decline during a 2-year follow-up. The polymorphism at position -670 was not associated with the risk of AD and with the cognitive decline during the follow-up. Our data suggest that different genetic background in the Fas gene may influence the risk and clinical progression of the disease by affecting neurodegenerative processes leading to neuronal loss.

MMP-7 promoter polymorphisms do not influence CD4+ recovery and changes in plasma viral load during antiretroviral therapy for HIV-1 infection.

Matrix metalloproteinase-7 (MMP-7) generates soluble Fas Ligand (FasL), which is involved in the apoptotic loss of CD4+ T cells during HIV infection. We evaluated whether two polymorphisms in MMP-7 promoter could influence CD4+ recover in response to antiretroviral therapy, and found that these polymorphisms are ineffective.

Impairment of recent thymic emigrants in HCV infection.

Hepatitis C Virus (HCV) often has a more favorable course in younger patients. Considering the involution of the thymic function with age, we investigated the output of recent thymic emigrants (RTE) in HCV patients. To evaluate RTE, we used a competitive quantitative PCR in order to determine the percentages of cells with cj-T cell receptor excision circles (TREC). This study was performed in 14 HCV patients at diagnosis and before any anti-HCV treatment. The results obtained in this group were compared to those obtained in a group of age-matched controls. We found that in the 14 HCV patients naive for anti-HCV treatment the mean percentage of cj-TREC was 3%. We could not detect a correlation between the percentages of cj-TREC and age or patients' viremia. In contrast, in the 26 age-matched controls mean percentage of cj-TREC was 5.6% (P=0.01). Our study describes a novel immune defect in HCV patients. Additional studies are needed to get further insight in the possible role of TREC defect in the pathogenesis and prognosis of the disease.

Hepatoma HepG2 cells as a model for in vitro studies on mitochondrial toxicity of antiviral drugs: which correlation with the patient?

Currently, drugs have been synthesised that can significantly delay the course of several viral infections, including those provoked by HBV, HCV or HIV, but that display consistent side effects, including toxicity for organelles such as mitochondria. Several in vitro models and techniques have been developed to analyse the effects of such compounds. HepG2 cells (from human hepatoma) are an excellent model to investigate mitochondrial (mt) toxicity because of their high content of organelles and mtDNA, and actually different investigators are indeed using such cells. Studies in vitro on cell lines are relatively easy, but it is necessary to be careful in the interpretation of data, which are usually obtained on continuously growing, tumour cells, quite different from normal, resting, non-neoplastic cells collected from a patient. Direct analysis of drug-induced mt damage in patients is extremely more complex than that performed using in vitro models because of the difficulty to obtain adequate cells or to have discrete amounts of biological material, the status of the patient at the moment of cell collection, the use of an adequate assay and its correct execution, and finally the possibility to find sex- and age-matched healthy controls as source of reference parameters.

Apoptosis-resistant phenotype in HL-60-derived cells HCW-2 is related to changes in expression of stress-induced proteins that impact on redox status and mitochondrial metabolism.

The onset of resistance to drug-induced apoptosis of tumour cells is a major problem in cancer therapy. We studied a drug-selected clone of promyelocytic HL-60 cells, called HCW-2, which display a complex resistance to a wide variety of apoptosis-inducing agents and we found that these cells show a dramatic increase in the expression of heat shock proteins (Hsps) 70 and 27, while the parental cell line does not. It is known that stress proteins such as Hsps can confer resistance to a variety of damaging agents other than heat shock, such as TNF-alpha, monocyte-induced cytotoxicity, and also play a role in resistance to chemotherapy. This elevated expression of Hsps is paralleled by an increased activity of mitochondrial metabolism and pentose phosphate pathway, this latter leading to high levels of glucose-6-phosphate dehydrogenase and, consequently, of glutathione. Thus, the apoptotic-deficient phenotype is likely because of the presence of high levels of stress response proteins and GSH, which may confer resistance to apoptotic agents, including chemotherapy drugs. Moreover, the fact that in HCW-2 cells Hsp70 are mainly localised in mitochondria may account for the increased performances of mitochondrial metabolism. These observations could have some implications for the therapy of cancer, and for the design of combined strategies that act on antioxidant defences of the neoplastic cell.

Ultraviolet B radiation induces activation of neutral and acidic sphingomyelinases and ceramide generation in cultured normal human keratinocytes.

The sphingomyelin pathway is an ubiquitous, evolutionary conserved signaling system which transduces an extracellular signal into the cell. During the past few years increasing evidence has shown that the sphingolipid ceramide may play a role as a second messenger in intracellular signal transduction. The ceramide generation via sphingomyelinase (SMase) is followed by three major cellular responses: cell growth arrest, induction of cell differentiation and/or induction of programmed cell death or apoptosis. The aim of this study is to investigate whether activation of SMases and generation of ceramide can be induced by UVB radiation in normal human keratinocytes. The present data show that exposure to UVB radiation results in rapid generation of ceramide. The ceramide accumulation starts 15 min after UV exposure and progressively increases up to 24 h. In vitro measurement of SMase activity following exposure to UVB evidences an activation of both neutral and acidic SMases. Moreover, UVB induces apoptosis in normal human keratinocytes as shown by TUNEL technique and FACS analysis. These data indicate that UVB induced ceramide generation and activation of both neutral and acidic SMases, suggesting that sphingolipids metabolism may be involved in the UVB signaling pathway.