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Pro-inflammatory cytokines, matrix metalloproteinases (MMPs) and other catabolic factors participate in the pathogenesis of cartilage damage in osteoarthritis (OA). Pro-inflammatory cytokines such as interleukin-1β (IL-1β) mediate cartilage degradation and might be involved in the progression of OA. Previously, we found that haem oxygenase-1 (HO-1) is down-regulated by pro-inflammatory cytokines and up-regulated by IL-10 in OA chondrocytes. The aim of this study was to determine whether HO-1 can modify the catabolic effects of IL-1β in OA cartilage and chondrocytes. Up-regulation of HO-1 by cobalt protoporphyrin IX significantly reduced glycosaminoglycan degradation elicited by IL-1β in OA cartilage explants but increased glycosaminoglycan synthesis and the expression of collagen II in OA chondrocytes in primary culture, as determined by radiometric procedures, immunoblotting and immunocytochemistry. HO-1 decreased the activation of extracellular signal-regulated kinase 1/2. This was accompanied by a significant inhibition in MMP activity and expression of collagenases MMP-1 and MMP-13 at the protein and mRNA levels. In addition, HO-1 induction caused a significant increase in the production of insulin-like growth factor-1 and a reduction in the levels of insulin-like growth factor binding protein-3. We have shown in primary culture of chondrocytes and articular explants from OA patients that HO-1 counteracts the catabolic and anti-anabolic effects of IL-1β. Our data thus suggest that HO-1 may be a factor regulating the degradation and synthesis of extracellular matrix components in OA. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Heme oxygenase 1 (HO-1) can be induced by inflammatory mediators as an adaptive response. The objective of the present study was to determine the consequences of HO-1 modulation in the murine collagen-induced arthritis (CIA) model. METHODS: DBA/1J mice were treated with an inhibitor of HO-1, tin protoporphyrin IX (SnPP), or with an inducer of HO-1, cobalt protoporphyrin IX (CoPP), from day 22 to day 29 after CIA induction. The clinical evolution of disease was monitored visually. At the end of the experiment, joints were examined for histopathologic changes. Cytokine levels in paws were measured by enzyme-linked immunosorbent assay. Levels of HO-1, cyclooxygenase 2 (COX-2), and prostaglandin E2 (PGE2) were determined. Effects of treatments on the early phase of disease and after prophylactic administration were also assessed. RESULTS: CoPP strongly induced HO-1, resulting in the inhibition of cartilage erosion accompanied by extensive fibrosis in the joint. Levels of tumor necrosis factor alpha (TNFalpha), interleukin-2 (IL-2), and IL-10 were inhibited by CoPP, whereas levels of vascular endothelial growth factor were increased. Treatment with SnPP significantly reduced the severity of CIA, with inhibition of joint inflammation and cartilage destruction. The levels of PGE2, IL-1beta, and TNFalpha were also significantly reduced by SnPP treatment, which did not modify COX-2 protein expression. SnPP was more effective than CoPP in preventing the development of CIA (prophylactic administration). CONCLUSION: HO-1 is induced during CIA. Although overexpression of this protein causes some beneficial effects, strategies aimed at HO-1 overexpression cannot slow the progression of the chronic inflammatory disease, whereas treatment with SnPP, which inhibits HO-1, exerts prophylactic and therapeutic effects. [ABSTRACT FROM AUTHOR]

The aqueous extract of Rhizophora mangle bark and its polyphenolic fractions showed remarkable in vitro antiinflammatory activity in a preliminary study. The low molecular weight fraction exhibited cyclooxygenase-2 inhibitory activity while the total aqueous extract and the low molecular weight fraction showed secretory phospholipase A(2) inhibitory activity. [ABSTRACT FROM AUTHOR]

The Platelia Aspergillus Antigen immunoassay is the "gold standard" for Aspergillus galactomannan (GLM) measurement in sera and bronchoalveolar lavage (BAL) for the diagnosis of invasive pulmonary aspergillosis (IPA). We evaluated the performance of the Aspergillus GLM antigen Virclia Monotest compared to the Platelia assay. A total of 535 specimens [320 sera, 86 bronchial aspirates (BAs), 70 BAL, and 59 tracheal aspirates (TAs)] from 177 adult patients (72 hematological, 32 Intensive Care Unit, and 73 hospitalized in other wards) were processed for GLM testing upon clinical request. One patient had proven IPA, and 11 had probable disease. After excluding indeterminate Virclia results ( n = 38), 396 specimens yielded concordant results (56 positive and 340 negative) and 101 discordant results (Virclia positive/Platelia negative, n = 95). The overall agreement between immunoassays was higher for sera ( κ 0.56) than for BAL ( κ ≤ 0.24) or BAS and TA ( κ ≤ 0.22). When considering all specimen types in combination, the overall sensitivity and specificity of the Virclia assay for the diagnosis of proven/probable IPA were 100% and 65%, respectively, and for the Platelia immunoassay, sensitivity and specificity were 91.7% and 89.4%, respectively. The correlation between index values by both immunoassays was strong for serum/BAL ( ρ = 0.73; P < 0.001) and moderate for BAS/TA (Rho = 0.52; P = 0.001). The conversion of Virclia index values into the Platelia index could be derived by the formula y = (11.97 * X )/3.62 + X ). Data from GLM-positive serum/BAL clinical specimens fitted the regression model optimally ( R 2 = 0.94), whereas that of BAS and TA data did not ( R 2 = 0.11). Further studies are needed to determine whether the Virclia assay may be an alternative to the Platelia assay for GLM measurement in sera and lower respiratory tract specimens.IMPORTANCEGalactomannan detection in serum or bronchoalveolar fluid specimens is pivotal for the diagnosis of invasive pulmonary aspergillosis (IPA). The Platelia Aspergillus Antigen immunoassay has become the "gold standard" for Aspergillus GLM measurement. Here, we provide data suggesting that the Virclia Monotest assay, which displays several operational advantages compared with the Platelia assay, may become an alternative to the Platelia assay, although further studies are needed to validate this assumption. We also provide a formula allowing the conversion of Virclia index values into Platelia values. The study may contribute toward positioning the Virclia assay within the diagnostic algorithm of IPA., Competing Interests: The authors declare no conflict of interest.

Purpose: The significant proportion of asymptomatic patients and the scarcity of genotypic analysis of lymphogranuloma venereum (LGV), mainly among men who have sex with men (MSM), triggers a high incidence of underdiagnosed patients, highlighting the importance of determining the most appropriate strategy for LGV diagnosis, at both clinical and economical levels., Materials and Methods: We conducted L1-L3 serovar detection by molecular biology in stored Chlamydia trachomatis-positive samples from MSM patients with HIV, another STI or belonging to a Pre-exposure prophylaxis program, to make a cost effectiveness study of four diagnostic strategies with a clinical, molecular, or mixed approach., Results: A total of 85 exudates were analyzed: 35urethral (31 symptomatic/4 positive) and 50 rectal (22 symptomatic/25 positive), 70/85 belonging to MSM with associated risk factors. The average cost per patient was €77.09 and €159.55 for clinical (Strategy I) and molecular (Strategy IV) strategies respectively. For molecular diagnosis by genotyping of all rectal exudate samples previously positive for CT (Strategy II), the cost was €123.84. For molecular diagnosis by genotyping of rectal and/or urethral exudate samples from all symptomatic patients (proctitis or urethritis) with a previous positive result for CT (Strategy III), the cost was €129.39. The effectiveness ratios were 0.80, 0.95, 0.91, and 1.00 for each strategy respectively. The smallest ICER was €311.67 for Strategy II compared to Strategy I., Conclusions: With 30% asymptomatic patients, the most cost-effective strategy was based on genotyping all rectal exudates. With less restrictive selection criteria, thus increasing the number of patients with negative results, the most sensitive strategies tend to be the most cost-effective, but with a high incremental cost-effectiveness ratio., (© 2024. The Author(s).)

Gouty arthritis results from monosodium urate (MSU) crystal deposition in joints, initiating (pro)-interleukin (IL)-1β maturation, inflammatory mediator release, and neutrophil infiltration, leading to joint swelling and pain. Parathyroid hormone-related protein (107-111) C-terminal peptide (osteostatin) has shown anti-inflammatory properties in osteoblasts and collagen-induced arthritis in mice, but its impact in gouty arthritis models remains unexplored. We investigated the effect of osteostatin on pyroptosis, inflammation, and oxidation in macrophages, as well as its role in the formation of calcium pyrophosphate dihydrate crystals and MSU-induced gouty arthritis in mice models. Osteostatin ameliorated pyroptosis induced by lipopolysaccharide and adenosine 5'-triphosphate (LPS + ATP) in mice peritoneal macrophages by reducing the expression of caspase-1, lactate dehydrogenase release, and IL-1β and IL-18 secretion. Additionally, IL-6 and tumor necrosis factor-α (TNF-α) were also decreased due to the reduced activation of the NF-κB pathway. Furthermore, osteostatin displayed antioxidant properties in LPS + ATP-stimulated macrophages, resulting in reduced production of mitochondrial and extracellular reactive oxygen species and enhanced Nrf2 translocation to the nuclei. In both models of gouty arthritis, osteostatin administration resulted in reduced pro-inflammatory cytokine production, decreased leukocyte migration, and reduced caspase-1 and NF-κB activation. These results highlight the potential of osteostatin as a therapeutic option for gouty arthritis.

The information provided by SARS-CoV-2 spike (S)-targeting immunoassays can be instrumental in clinical-decision making. We compared the performance of the Elecsys® Anti-SARS-CoV-2 S assay (Roche Diagnostics) and the LIAISON® SARS-CoV-2 TrimericS IgG assay (DiaSorin) using a total of 1176 sera from 797 individuals, of which 286 were from vaccinated-SARS-CoV-2/experienced (Vac-Ex), 581 from vaccinated/naïve (Vac-N), 147 from unvaccinated/experienced (Unvac-Ex), and 162 from unvaccinated/naïve (Unvac-N) individuals. The Roche assay returned a higher number of positive results (907 vs. 790; p = 0.45; overall sensitivity: 89.3% vs. 77.6%). The concordance between results provided by the two immunoassays was higher for sera from Vac-N (ϰ: 0.58; interquartile ranges [IQR]: 0.50-0.65) than for sera from Vac-Ex (ϰ: 0.19; IQR: -0.14 to 0.52) or Unvac-Ex (ϰ: 0.18; IQR: 0.06-0.30). Discordant results occurred more frequently among sera from Unvac-Ex (34.7%) followed by Vac-N (14.6%) and Vac-Ex (2.7%). Antibody levels quantified by both immunoassays were not significantly different when <250 (p = 0.87) or <1000 BAU/ml (p = 0.13); in contrast, for sera ≥1000 BAU/ml, the Roche assay returned significantly higher values than the DiaSorin assay (p < 0.008). Neutralizing antibody titers (NtAb) were measured in 127 sera from Vac-Ex or Vac-N using a S-pseudotyped virus neutralization assay of Wuhan-Hu-1, Omicron BA.1, and Omicron BA.2. The correlation between antibody levels and NtAb titers was higher for sera from Vac-N than those from Vac-Ex, irrespective of the (sub)variant considered. In conclusion, neither qualitative nor quantitative results returned by both immunoassays are interchangeable. The performance of both assays was found to be greatly influenced by the vaccination and SARS-CoV-2 infection status of individuals., (© 2022 The Authors. Journal of Medical Virology published by Wiley Periodicals LLC.)

Studies investigating the cumulative incidence of and immune status against SARS-CoV-2 infection provide valuable information for shaping public health decision-making. A cross-sectional study on 935 participants, conducted in the Valencian Community (VC), measuring anti-SARS-CoV-2-receptor binding domain-RBD-total antibodies and anti-Nucleocapsid (N)-IgGs via electrochemiluminescence assays. Quantitation of neutralizing antibodies (NtAb) against ancestral and Omicron BA.1 and BA.2 variants and enumeration of SARS-CoV-2-S specific-IFNγ-producing CD4 + and CD8 + T cells was performed in 100 and 137 participants, respectively. The weighted cumulative incidence was 51.9% (95% confidence interval [CI]: 48.7-55.1) and was inversely related to age. Anti-RBD total antibodies were detected in 97% of participants; vaccinated and SARS-CoV-2-experienced (VAC-ex; n = 442) presented higher levels (p < 0.001) than vaccinated/naïve (VAC-n; n = 472) and nonvaccinated/experienced (UNVAC-ex; n = 63) subjects. Antibody levels correlated inversely with time elapsed since last vaccine dose in VAC-n (Rho, -0.52; p < 0.001) but not in VAC-ex (rho -0.02; p = 0.57). Heterologous booster shots resulted in increased anti-RBD antibody levels compared with homologous schedules in VAC-n, but not in VAC-ex. NtAbs against Omicron BA.1 were detected in 94%, 75%, and 50% of VAC-ex, VAC-n and UNVAC-ex groups, respectively. For Omicron BA.2, the figures were 97%, 84%, and 40%, respectively. SARS-CoV-2-S-reactive IFN-γ T cells were detected in 73%, 75%, and 64% of VAC-ex, VAC-n and UNVAC-ex, respectively. Median frequencies for both T-cell subsets were comparable across groups. In summary, by April 2022, around half of the VC population had been infected with SARS-CoV-2 and, due to extensive vaccination, displayed hybrid immunity., (© 2022 The Authors. Journal of Medical Virology published by Wiley Periodicals LLC.)

Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes progressive joint destruction. Despite the advances in the treatment of this condition there remains a clinical need for safe therapies leading to clinical remission. Mesenchymal stem/stromal cells (MSCs) play immunomodulatory and regenerative roles which can be partly mediated by their secretome. In recent years, the important contribution of extracellular vesicles (EVs) to MSC actions has received an increasing interest as a new therapeutic approach. We provide an extensive overview of the immunomodulatory properties of MSC EVs and their effects on articular cells such as fibroblast-like synoviocytes that play a central role in joint destruction. This review discusses the anti-arthritic effects of MSC EVs in vitro and in animal models of RA as well as their potential mechanisms. Recent preclinical data suggest that transfer of non-coding RNAs by MSC EVs regulates key signaling pathways involved in the pathogenesis of RA. We also examine a number of EV modifications for improving their anti-arthritic efficacy and carrier ability for drug delivery., (© The Author(s) 2022. Published by Oxford University Press.)

The effect of a third vaccine dose (3D) of homologous mRNA vaccine on blood levels of SARS-CoV-2-receptor binding domain (RBD)-total antibodies was assessed in 40 hemodialysis patients (HD) and 21 kidney transplant recipients (KTR) at a median of 46 days after 3D. Anti-RBD antibodies were detected in 39/40 HD and 19/21 KTR. Overall, 3D boosted anti-RBD antibody levels (median: 58-fold increase). Neutralizing antibodies (NtAb) against the Wuhan-Hu-1, Delta, and Omicron variants were detected in 14, 13, and 11 out of 14 HD patients, and in 5, 5, and 4 out of 8 KTR patients, respectively. The median fold increase in NtAb titers in HD patients was 77, 28, and 5 and 56, 37, and 9 in KTR patients for each respective variant. SARS-CoV-2-S S-IFN-γ-producing CD8 + and CD4 + T-cell responses were detected in the majority of HD (35 and 36/37, respectively) and all KTR (16/16) patients at 3D. Overall, the administration of 3D boosted T-cell levels in both population groups. In conclusion, a homologous mRNA COVID-19 vaccine 3D exerts a booster effect on anti-RBD antibodies, NtAb binding to Wuhan-Hu-1, Delta, and Omicron variants, and SARS-CoV-2-S-IFN-γ-producing T cells in both HD and KTR patients. The magnitude of the effect was more marked in HD than KTR patients.

Parathyroid hormone-related protein (PTHrP) C-terminal peptides regulate the metabolism of bone cells. PHTrP [107-111] (osteostatin) promotes bone repair in animal models of bone defects and prevents bone erosion in inflammatory arthritis. In addition to its positive effects on osteoblasts, osteostatin may inhibit bone resorption. The aim of this study was to determine the effects of osteostatin on human osteoclast differentiation and function. We used macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κB ligand (RANKL) to induce the osteoclast differentiation of adherent human peripheral blood mononuclear cells. Tartrate-resistant acid phosphatase (TRAP) staining was performed for the detection of the osteoclasts. The function of mature osteoclasts was assessed with a pit resorption assay. Gene expression was evaluated with qRT-PCR, and nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) nuclear translocation was studied by immunofluorescence. We observed that osteostatin (100, 250 and 500 nM) decreased the differentiation of osteoclasts in a concentration-dependent manner, but it did not modify the resorptive ability of mature osteoclasts. In addition, osteostatin decreased the mRNA levels of cathepsin K, osteoclast associated Ig-like receptor (OSCAR) and NFATc1. The nuclear translocation of the master transcription factor in osteoclast differentiation NFATc1 was reduced by osteostatin. Our results suggest that the anti-resorptive effects of osteostatin may be dependent on the inhibition of osteoclastogenesis. This study has shown that osteostatin controls human osteoclast differentiation in vitro through the downregulation of NFATc1.

Background: Little is known regarding the dynamics of antibody and T-cell responses in chronic kidney disease (CKD) following coronavirus disease 2019 (COVID-19) vaccination., Methods: Prospective observational cohort study including 144 participants on haemodialysis (HD) ( n = 52) or peritoneal dialysis (PD) ( n = 14), those undergoing kidney transplantation (KT) ( n = 30) or those with advanced CKD (ACKD) not on dialysis and healthy controls ( n = 18). Anti-Spike (S) antibody and T-cell responses were assessed at 15 days (15D) and 3 months (3M) after complete vaccination schedule. HD, PD and KT patients received mRNA vaccines (mRNA-123 and BNT162b2). Most ACKD patients received BNT162b2 ( n = 23), or Ad26.COV.2.S (4). Most controls received BNT162b2 ( n = 12), or Ad26.COV.2.S ( n = 5)., Results: Anti-S antibodies at 15D and 3M were detectable in 95% (48/50)/98% (49/50) of HD patients, 93% (13/14)/100% of PD patients, 67% (17/26)/75% (21/28) of KT patients and 96% (25/26)/100% (24/24) of ACKD patients. Rates for healthy controls were 81% (13/16)/100% (17/17). Previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2-S) infection was documented in four (7.7%) HD patients, two (14.3%) PD patients, two (6.7%) KT patients, one (5.55%) healthy control and in no ACKD patient. Antibody levels decreased at 3M in HD ( P = .04), PD ( P = .008) and ACKD patients ( P = .0009). In KT patients, levels increased ( P = .04) between 15D and 3M, although they were low at both time points.T-cell responses were detected in HD patients in 37 (80%) at baseline, 35 (70%) at 15D and 41 (91%) at 3M. In PD patients, T-cell responses appeared in 8 (67%) at baseline, 13 (93%) at 15D and 9 (100%) at 3M. In KT patients, T-cell responses were detected in 12 (41%) at baseline, 22 (84%) at 15D and 25 (96%) at 3M. In ACKD patients, T-cell responses were detected in 13 (46%) at baseline, 20 (80%) at 15D and 17 (89%) at 3M. None of healthy controls showed T-cell response at baseline, 10 (67%) at 15D and 8 (89%) at 3M., Conclusions: Most HD, PD and ACKD patients develop SARS-CoV-2-S antibody responses comparable to that of healthy controls, in contrast to KT recipients. Antibody waning at 3M was faster in HD, PD and ACKD patients. No differences in SARS-CoV-2 T-cell immunity responses were noticed across study groups., (© The Author(s) 2022. Published by Oxford University Press on behalf of the ERA.)

The performance of a laboratory-developed IgG/IgA flow cytometry-based immunoassay (FCI) using Jurkat T cells stably expressing full-length native S protein was compared against Elecsys electrochemiluminiscent (ECLIA) Anti-SARS-CoV-2 S (Roche Diagnostics, Pleasanton, CA, USA), and Liaison SARS-CoV-2 TrimericS IgG chemiluminiscent assay (CLIA) (Diasorin S.p.a, Saluggia, IT) for detection of SARS-CoV-2-specific antibodies. A total of 225 serum/plasma specimens from 120 acute or convalescent COVID-19 individuals were included. Overall, IgG/IgA-FCI yielded the highest number of positives (n = 179), followed by IgA-FCI (n = 177), Roche ECLIA (n = 175), IgG-FCI (n = 172) and Diasorin CLIA (n = 154). For sera collected early after the onset of symptoms (within 15 days) IgG/IgA-FCI also returned the highest number of positive results (52/72; 72.2%). Positive percent agreement between FCI and compared immunoassays was highest for Roche ECLIA, ranging from 96.1 (IgG/IgA-FCI) to 97.7% (IgG-FCI), whereas negative percent agreement was higher between FCI and Diasosin CLIA, regardless of antibody isotype. The data suggest that FCI may outperform Roche ECLIA and Diasorin CLIA in terms of clinical sensitivity for serological diagnosis of SARS-CoV-2 infection., (© 2022. The Author(s).)

Background: Physical activity has anti-inflammatory effects and reduces morbidity and mortality in the general population, but its role in the clinical, CD4/CD8 ratio, and immune activation status of HIV-infected patients has been poorly studied., Methods: A cross-sectional study was carried out in a cohort of 155 HIV-infected patients on stable antiretroviral therapy (ART) to compare clinical, biochemical, CD4/CD8 ratio, and immune activation status according to their physical activity in the last 2 years (sedentary/low vs moderate/intense) assessed by the iPAQ. A binary logistic regression and mixed analysis of variance were performed to evaluate the impact of levels of physical activity on CD4/CD8 ratio., Results: In our series, 77 (49.7%) out of 155 patients were sedentary, and 78 (50.3%) practiced moderate/intense physical activity. Moderate/intense physical activity was associated with better metabolic control (lower body mass index, P  = .024; glucose, P  = .024; and triglyceride, P  = .002) and CDC HIV stage ( P  = .046), lower CD8 + ( P  =  .018), CD4 + CD8 + ( P  = .026), CD4 + CD86 + ( P  = .045), CD4 + HLA-DR + ( P  = .011), CD8 + HLA-DR + ( P  = .048) T lymphocytes and CD16 + HLA-DR + natural killer cells ( P  = .026), and higher CD3 + CD4 + T lymphocytes ( P  = .016) and CD4/CD8 ratio ( P  = .001). Sedentary lifestyle (odds ratio [OR], 2.12; P  = .042), CD4 nadir (OR, 1.005; P  < .001), and CD8 + CD38 + T cells (OR, 1.27; P  = .006) were independently associated with low CD4/CD8 ratio (<0.8). Earlier and more intense CD4/CD8 ratio recovery was observed in patients with higher physical activity in the 2-year follow-up with a significant interaction between these variables: F(2, 124) = 3.31; P  = .049; partial η2 = 0.042., Conclusions: Moderate to high physical activity is associated with beneficial health effects, improvement in metabolic profile, and reduction of chronic inflammation in patients with HIV. Although more studies and clinical trials are needed to confirm these findings, a healthy lifestyle including at least moderate physical activity should be recommended to HIV patients on stable ART., (© The Author(s) 2021. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Objectives: The immunogenicity of the Comirnaty® vaccine against coronavirus disease 2019 (COVID-19) has not been adequately studied in elderly people with comorbidities. We assessed antibody and T-cell responses targeted to the S protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) following full vaccination in nursing-home residents., Methods: Sixty nursing-home residents (44 female, age 53-100 years), of whom ten had previously been diagnosed with COVID-19, and 18 healthy controls (15 female, age 27-54 years) were recruited. Pre- and post-vaccination blood specimens were available for quantification of total antibodies binding the SARS-CoV-2 S protein and for enumeration of SARS-CoV-2 S-reactive IFN-γ CD4 + and CD8 + T cells by flow cytometry., Results: The seroconversion rate in (presumably) SARS-CoV-2-naïve nursing-home residents (41/43, 95.3%) was similar to that in controls (17/18, 94.4%). A booster effect was documented in post-vaccination samples of nursing-home residents with prior COVID-19. Plasma antibody levels were higher (p < 0.01) in recovered nursing-home residents (all 2500 IU/mL) than in individuals across the other two groups (median 1120 IU/mL in naïve nursing-home residents and 2211 IU/ml in controls). A large percentage of nursing-home residents had SARS-CoV-2 S-reactive IFN-γ CD8 + (naïve 31/49, 63.2%; recovered 8/10, 80%) or CD4 + T cells (naïve 35/49, 71.4%; recovered 7/10, 70%) at baseline, in contrast to healthy controls (3/17, 17.6% and 5/17, 29%, respectively). SARS-CoV-2 IFN-γ CD8 + and CD4 + T-cell responses were documented in 88% (15/17) and all control subjects after vaccination, respectively, but only in 65.5% (38/58) and 22.4% (13/58) of nursing-home residents. Overall, the median frequency of SARS-CoV-2 IFN-γ CD8 + and CD4 + T cells in nursing-home residents decreased in post-vaccination specimens, whereas it increased in controls., Conclusion: The Comirnaty COVID-19 vaccine elicits robust SARS-CoV-2 S antibody responses in nursing-home residents. Nevertheless, the rate and frequency of detectable SARS-CoV-2 IFN-γ T-cell responses after vaccination was lower in nursing-home residents than in controls., (Copyright © 2021 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Osteoarthritis (OA) is a joint disease characterized by cartilage degradation, low-grade synovitis and subchondral bone alterations. In the damaged joint, there is a progressive increase of oxidative stress leading to disruption of chondrocyte homeostasis. The modulation of oxidative stress could control the expression of inflammatory and catabolic mediators involved in OA. We have previously demonstrated that extracellular vesicles (EVs) present in the secretome of human mesenchymal stem cells from adipose tissue (AD-MSCs) exert anti-inflammatory and anti-catabolic effects in OA chondrocytes. In the current work, we have investigated whether AD-MSC EVs could regulate oxidative stress in OA chondrocytes as well as the possible contribution of peroxiredoxin 6 (Prdx6)., Methods: Microvesicles (MV) and exosomes (EX) were isolated from AD-MSC conditioned medium by differential centrifugation with size filtration. The size and concentration of EVs were determined by resistive pulse sensing. OA chondrocytes were isolated from knee articular cartilage of advanced OA patients. 4-Hydroxynonenal adducts, IL-6 and MMP-13 were determined by enzyme-linked immunosorbent assay. Expression of Prdx6 and autophagic markers was assessed by immunofluorescence and Western blotting. Prdx6 was downregulated in AD-MSCs by transfection with a specific siRNA., Results: MV and to a lesser extent EX significantly reduced the production of oxidative stress in OA chondrocytes stimulated with IL-1β. Treatment with MV resulted in a dramatic upregulation of Prdx6. MV also enhanced the expression of autophagy marker LC3B. We downregulated Prdx6 in AD-MSCs by using a specific siRNA and then MV were isolated. These Prdx6-silenced MV failed to modify oxidative stress and the expression of autophagy markers. We also assessed the possible contribution of Prdx6 to the effects of MV on IL-6 and MMP-13 production. The reduction in the levels of both mediators induced by MV was partly reverted after Prdx6 silencing., Conclusion: Our results indicate that EVs from AD-MSCs regulate the production of oxidative stress in OA chondrocytes during inflammation. Prdx6 may mediate the antioxidant and protective effects of MV. The translational potential of this article: This study gives insight into the protective properties of EVs from AD-MSCs in OA chondrocytes. Our findings support the development of novel therapies based on EVs to prevent or treat cartilage degradation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2021 The Authors.)

Background: To date, available data on premature aging in young HIV-infected adults are scarce and no reports offer comprehensive assessment of telomere shortening (TS) in relation to subclinical atherosclerosis (SCA). In this study, we investigate if telomere shortening and immune activation markers are associated with SCA, which is one of the main degenerative diseases in young HIV-infected adults., Methods: A descriptive cross-sectional study was carried out in 149 HIV-infected patients on stable antiretroviral regimen (ART). Carotid intima-media thickness (cIMT) was estimated by carotid ultrasound. Quantitative singleplex PCR was performed to evaluate TS. The expression of activation/senescence markers was evaluated by multiparametric flow cytometry., Results: TS was observed in 73 patients (49%). Higher cIMT was observed in patients with TS than those without it (0.86 vs. 0.80 mm; p=0.041). Patients under the age of 50 (defined as young adults) with TS showed higher absolute numbers of activated lymphocyte T cells CD8+CD38+ (3.94 vs. 2.34 cell/μl; p=0.07) and lymphocyte B cells CD19+CD38+ (3.07 vs. 2.10 cell/μl; p=0.004) compared to those without TS. In the multivariate analysis, the only factor independently associated with TS was the absolute number of lymphocyte T cells CD8+CD38+ T cells (OR = 1.18; 95%-CI = 1.00-1.39; p = 0.05)., Conclusion: Young HIV-infected adults show premature biological aging with accentuated immune activation. Chronic inflammation with excessive T-cells activation could be associated to TS, premature aging, and SCA in young HIV-infected adults.

Background: Etiopathogenesis of the clinical variability of the coronavirus disease 2019 (COVID-19) remains mostly unknown. In this study, we investigate the role of killer cell immunoglobulin-like receptor (KIR)/human leukocyte antigen class-I (HLA-I) interactions in the susceptibility and severity of COVID-19., Methods: We performed KIR and HLA-I genotyping and natural killer cell (NKc) receptors immunophenotyping in 201 symptomatic patients and 210 noninfected controls., Results: The NKcs with a distinctive immunophenotype, suggestive of recent activation (KIR2DS4low CD16low CD226low CD56high TIGIThigh NKG2Ahigh), expanded in patients with severe COVID-19. This was associated with a higher frequency of the functional A-telomeric activating KIR2DS4 in severe versus mild and/or moderate patients and controls (83.7%, 55.7% and 36.2%, P < 7.7 × 10-9). In patients with mild and/or moderate infection, HLA-B*15:01 was associated with higher frequencies of activating B-telomeric KIR3DS1 compared with patients with other HLA-B*15 subtypes and noninfected controls (90.9%, 42.9%, and 47.3%; P < .002; Pc = 0.022). This strongly suggests that HLA-B*15:01 specifically presenting severe acute respiratory syndrome coronavirus 2 peptides could form a neoligand interacting with KIR3DS1. Likewise, a putative neoligand for KIR2DS4 could arise from other HLA-I molecules presenting severe acute respiratory syndrome coronavirus 2 peptides expressed on infected an/or activated lung antigen-presenting cells., Conclusions: Our results support a crucial role of NKcs in the clinical variability of COVID-19 with specific KIR/ligand interactions associated with disease severity., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objectives: To evaluate four sample treatments in a safe and straightforward procedure to detect SARS-CoV-2 in saliva., Methods: Four sample treatments were evaluated in a 3-step procedure to detect SARS-CoV-2 in saliva: 1) heating at 95 °C for 5 min for sample inactivation; 2) sample treatment; 3) analysis by reverse-transcription loop-mediated isothermal amplification (LAMP). Saliva samples used were from infected individuals or were spiked with known quantities of viral particles., Results: Three treatments had a limit of detection (LOD) of 500.000 viral particles per ml of saliva and could be used to detect individuals with potential to transmit the disease. The treatment of phosphate buffer, dithiothreitol, ethylenediaminetetraacetic acid and proteinase K, with an additional 95 °C heating step, yielded a lower LOD of 95; its sensitivity ranged from 100% in patients with nasopharyngeal swab reverse-transcriptase polymerase chain reaction cycle threshold values <20 to 47.8% for values >30., Conclusions: This report highlights the importance of an adequate sample treatment for saliva to detect SARS-CoV-2 and describes a flexible procedure that can be adapted to point-of-care. Although its sensitivity when LAMP is used is lower than reverse-transcriptase polymerase chain reaction, this procedure can contribute to COVID-19 control by detecting individuals able to transmit the disease., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objectives: The aim of the present study was to validate a commercially available automated assay for the measurement of total adenosine deaminase (tADA) and its isoenzymes (ADA1 and ADA2) in saliva in a fast and accurate way, and evaluate the possible changes of these analytes in individuals with SARS-CoV-2 infection., Methods: The validation, in addition to the evaluation of precision and accuracy, included the analysis of the effects of the main procedures that are currently being used for SARS-CoV-2 inactivation in saliva and a pilot study to evaluate the possible changes in salivary tADA and isoenzymes in individuals infected with SARS-CoV-2., Results: The automated assay proved to be accurate and precise, with intra- and inter-assay coefficients of variation below 8.2%, linearity under dilution linear regression with R 2 close to 1, and recovery percentage between 80 and 120% in all cases. This assay was affected when the sample is treated with heat or SDS for virus inactivation but tolerated Triton X-100 and NP-40. Individuals with SARS-CoV-2 infection (n=71) and who recovered from infection (n=11) had higher mean values of activity of tADA and its isoenzymes than healthy individuals (n=35)., Conclusions: tADA and its isoenzymes ADA1 and ADA2 can be measured accurately and precisely in saliva samples in a rapid, economical, and reproducible way and can be analyzed after chemical inactivation with Triton X-100 and NP-40. Besides, the changes observed in tADA and isoenzymes in individuals with COVID-19 open the possibility of their potential use as non-invasive biomarkers in this disease., (© 2021 Walter de Gruyter GmbH, Berlin/Boston.)

Whether antibody levels measured by commercially available enzyme or chemiluminescent immunoassays targeting the SARS-CoV-2 spike (S) protein can act as a proxy for serum neutralizing activity remains to be established for many of these assays. We evaluated the degree of correlation between neutralizing antibodies (NtAb) binding the SARS-CoV-2 spike (S) protein and SARS-CoV-2-S-IgG levels measured by four commercial immunoassays in sera drawn from hospitalized COVID-19 patients. Ninety sera from 51 hospitalized COVID-19 patients were tested by a pseudotyped virus neutralization assay, the LIAISON SARS-CoV-2 S1/S2 IgG, the Euroimmun SARS-CoV-2 IgG ELISA, the MAGLUMI 2019-nCoV IgG, and the COVID-19 ELISA IgG assays. Overall, the results obtained with the COVID-19 ELISA IgG test showed the highest agreement with the NtAb assay (κ, 0.85; 95% CI, 0.63-1). The most sensitive tests were the pseudotyped virus NtAb assay and the COVID-19 ELISA IgG assay (92.2% for both). Overall, the degree correlation between antibody titers resulting in 50% virus neutralization (NtAb 50 ) in the pseudotyped virus assay and SARS-CoV-2 IgG levels was strong for the Euroimmun SARS-CoV-2 IgG ELISA (rho = 0.73) and moderate for the remaining assays (rho = 0.48 to 0.59). The kinetic profile of serum NtAb 50 titers could not be reliably predicted by any of the SARS-CoV-2 IgG immunoassays. The suitability of SARS-CoV-2-S-IgG commercial immunoassays for inferring neutralizing activity of sera from hospitalized COVID-19 patients varies widely across tests and is influenced by the time of sera collection after the onset of symptoms.

Knowledge of the precise timing of SARS-CoV-2 infection may be of clinical and epidemiological relevance. The presence of low-avidity IgGs has conventionally been considered an indicator of recent infection. Here, we carried out qualitative assessment of SARS-CoV-2-specific antibody avidity using an urea (6M) dissociation test performed on a lateral flow immunochromatographic IgG/IgM device. We included a total of 76 serum specimens collected from 57 COVID-19 patients, of which 39 tested positive for both IgG and IgM and 37 only for IgG. Sera losing IgG reactivity after urea treatment (n = 28) were drawn significantly earlier (P = .04) after onset of symptoms than those which preserved it (n = 48). This assay may be helpful to estimate the time of acquisition of infection in patients with mild to severe COVID-19., (© 2020 Wiley Periodicals LLC.)

Adipose tissue represents an abundant source of mesenchymal stem cells (MSC) for therapeutic purposes. Previous studies have demonstrated the anti-inflammatory potential of adipose tissue-derived MSC (ASC). Extracellular vesicles (EV) present in the conditioned medium (CM) have been shown to mediate the cytoprotective effects of human ASC secretome. Nevertheless, the role of EV in the anti-inflammatory effects of mouse-derived ASC is not known. The current study has investigated the influence of mouse-derived ASC CM and its fractions on the response of mouse-derived peritoneal macrophages against lipopolysaccharide (LPS). CM and its soluble fraction reduced the release of pro-inflammatory cytokines, adenosine triphosphate and nitric oxide in stimulated cells. They also enhanced the migration of neutrophils or monocytes, in the absence or presence of LPS, respectively, which is likely related to the presence of chemokines, and reduced the phagocytic response. The anti-inflammatory effect of CM may be dependent on the regulation of toll-like receptor 4 expression and nuclear factor-κB activation. Our results demonstrate the anti-inflammatory effects of mouse-derived ASC secretome in mouse-derived peritoneal macrophages stimulated with LPS and show that they are not mediated by EV.

Adipose tissue-derived mesenchymal stem cells (AD-MSCs) offer great therapeutic potential for osteoarthritis (OA) treatment. Recent investigations have revealed the contribution of extracellular vesicles (EVs) to AD-MSC actions. Here, we describe a method to study the in vitro effects of EVs from AD-MSCs in OA chondrocytes. This chapter includes the isolation and analysis of human AD-MSCs and their EVs as well as the isolation and treatment of OA chondrocytes.

There is limited information on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) T-cell immune responses in patients with coronavirus disease 2019 (COVID-19). Both CD4+ and CD8+ T cells may be instrumental in resolution of and protection from SARS-CoV-2 infection. Here, we tested 25 hospitalized patients either with microbiologically documented COVID-19 (n = 19) or highly suspected of having the disease (n = 6) for presence of SARS-CoV-2-reactive CD69+ expressing interferon-γ (IFN-γ) producing CD8+ T cells using flow-cytometry for intracellular cytokine staining assay. Two sets of overlapping peptides encompassing the SARS-CoV-2 Spike glycoprotein N-terminal 1 to 643 amino acid sequence and the entire sequence of SARS-CoV-2 M protein were used simultaneously as antigenic stimulus. Ten patients (40%) had detectable responses, displaying frequencies ranging from 0.15 to 2.7% (median of 0.57 cells/µL; range, 0.43-9.98 cells/µL). The detection rate of SARS-CoV-2-reactive IFN-γ CD8+ T cells in patients admitted to intensive care was comparable (P = .28) to the rate in patients hospitalized in other medical wards. No correlation was found between SARS-CoV-2-reactive IFN-γ CD8+ T-cell counts and SARS-CoV-2 S-specific antibody levels. Likewise, no correlation was observed between either SARS-CoV-2-reactive IFN-γ CD8+ T cells or S-specific immunoglobulin G-antibody titers and blood cell count or levels of inflammatory biomarkers. In summary, in this descriptive, preliminary study we showed that SARS-CoV-2-reactive IFN-γ CD8+ T cells can be detected in a non-negligible percentage of patients with moderate to severe forms of COVID-19. Further studies are warranted to determine whether quantitation of these T-cell subsets may provide prognostic information on the clinical course of COVID-19., (© 2020 Wiley Periodicals LLC.)