Analysis of physical activity and plasma levels of soluble CD40 and CD40L in older people with gastrointestinal tract cancer.

Regular physical activity prevents and treats cancer patients by assisting and improving the immune system. Co-stimulatory molecules that activate the immune system have been studied in cancer, such as immune checkpoint molecules of the CD40/CD40L pathway. This study aimed to characterize plasma levels of soluble CD40 (sCD40) and CD40 ligand (sCD40L) in older people with gastrointestinal tract (GIT) cancer and associate results with physical activity. This prospective and exploratory cohort study was performed with 24 older people with GIT cancer and 23 healthy elderly individuals as controls. Physical activity level was classified as active or sedentary according to the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Plasma levels of sCD40 and sCD40L were determined using Enzyme-Linked Immunosorbent Assay. Plasma levels of sCD40 were higher, while sCD40L were lower (p = 0.0171) in older people with GIT cancer than controls (p = 0.0038). Regarding physical activity, active older people with GIT cancer presented lower plasma levels of sCD40 and sCD40L than those sedentary with GIT cancer (p = 0.0228 and p = 0.0236), respectively. Our findings suggest that GIT cancer stimulates the immune system in older people, elevates levels of sCD40, and reduces levels of sCD40L. Physical activity may be a protective factor for the immune system of these patients since it acts on sCD40/sCD40L pathway.

Dysregulated CD40 and CD40 ligand expression in anti-N-methyl-d-aspartate receptor encephalitis.

Anti-N-methyl-d-aspartate receptor encephalitis (anti-NMDARE) is a B cell- and antibody-mediated autoimmune disease which may be regulated by CD40/CD40L signaling pathway. we enrolled anti-NMDARE patients and measured the serum CD40 and CD40L concentrations. The serum concentration of CD40 was decreased, while CD40L was increased in anti-NMDARE patients compared with that of healthy controls. The concentrations of CD40 and CD40L were both elevated in the acute stage of anti-NMDARE and were reduced during remission. Serum CD40L levels were positively correlated with serum CD40 levels. These results revealed that the CD40/CD40L signaling pathway might contribute to the pathogenesis of anti-NMDARE.

Platelets mediate inflammatory monocyte activation by SARS-CoV-2 spike protein.

Infection with SARS-CoV-2, the causative agent of COVID-19, causes mild to moderate disease in most patients but carries a risk of morbidity and mortality. Seriously affected individuals manifest disorders of hemostasis and a cytokine storm, but it is not understood how these manifestations of severe COVID-19 are linked. Here, we showed that the SARS-CoV-2 spike protein engaged the CD42b receptor to activate platelets via 2 distinct signaling pathways and promoted platelet-monocyte communication through the engagement of P selectin/PGSL-1 and CD40L/CD40, which led to proinflammatory cytokine production by monocytes. These results explain why hypercoagulation, monocyte activation, and a cytokine storm are correlated in patients severely affected by COVID-19 and suggest a potential target for therapeutic intervention.

The circulating soluble form of the CD40 costimulatory immune checkpoint receptor and liver metastasis risk in rectal cancer.

BACKGROUND: In colorectal cancer, the inflamed tumour microenvironment with its angiogenic activities is immune- tolerant and incites progression to liver metastasis. We hypothesised that angiogenic and inflammatory factors in serum samples from patients with non-metastatic rectal cancer could inform on liver metastasis risk. METHODS: We measured 84 angiogenic and inflammatory markers in serum sampled at the time of diagnosis within the population-based cohort of 122 stage I-III patients. In a stepwise manner, the statistically strongest proteins associated with time to development of liver metastasis were analysed in the corresponding serum samples from 273 stage II-III rectal cancer patients in three independent cohorts. RESULTS: We identified the soluble form of the costimulatory immune checkpoint receptor cluster of differentiation molecule 40 (sCD40) as a marker of liver metastasis risk across all patient cohorts-the higher the sCD40 level, the shorter time to liver metastasis. In patients receiving neoadjuvant treatment, the sCD40 value remained an independent variable associated with progression to liver metastasis along with the local treatment response. Of note, serum sCD40 was not associated with progression to lung metastasis. CONCLUSIONS: Circulating sCD40 is a marker of liver metastasis risk in rectal cancer and may be developed for use in clinical practice.

An extracellular vesicle epitope profile is associated with acute myocardial infarction.

The current standard biomarker for myocardial infarction (MI) is high-sensitive troponin. Although powerful in clinical setting, search for new markers is warranted as early diagnosis of MI is associated with improved outcomes. Extracellular vesicles (EVs) attracted considerable interest as new blood biomarkers. A training cohort used for diagnostic modelling included 30 patients with STEMI, 38 with stable angina (SA) and 30 matched-controls. Extracellular vesicle concentration was assessed by nanoparticle tracking analysis. Extracellular vesicle surface-epitopes were measured by flow cytometry. Diagnostic models were developed using machine learning algorithms and validated on an independent cohort of 80 patients. Serum EV concentration from STEMI patients was increased as compared to controls and SA. EV levels of CD62P, CD42a, CD41b, CD31 and CD40 increased in STEMI, and to a lesser extent in SA patients. An aggregate marker including EV concentration and CD62P/CD42a levels achieved non-inferiority to troponin, discriminating STEMI from controls (AUC = 0.969). A random forest model based on EV biomarkers discriminated the two groups with 100% accuracy. EV markers and RF model confirmed high diagnostic performance at validation. In conclusion, patients with acute MI or SA exhibit characteristic EV biomarker profiles. EV biomarkers hold great potential as early markers for the management of patients with MI.

Analysis of serum inflammatory mediators in type 2 diabetic patients and their influence on renal function.

AIM: To evaluate the serum concentrations of inflammatory mediators in patients with type 2 diabetes mellitus (T2DM) with or without renal alteration (RA) function. METHODS: Serum samples from 76 patients with T2DM and 24 healthy individuals were selected. Patients with T2DM were divided into two groups according to eGFR (> or < 60mL/min/1.73m2). Cytokines, chemokines and adipokines levels were evaluated using the Multiplex immunoassay and ELISA. RESULTS: TNFR1 and leptin were higher in the T2DM group with RA than in the T2DM group without RA and control group. All patients with T2DM showed increased resistin, IL-8, and MIP-1α compared to the control group. Adiponectin were higher and IL-4 decreased in the T2DM group with RA compared to the control group. eGFR positively correlated with IL-4 and negatively with TNFR1, TNFR2, and leptin in patients with T2DM. In the T2DM group with RA, eGFR was negatively correlated with TNFR1 and resistin. TNFR1 was positively correlated with resistin and leptin, as well as resistin with IL-8 and leptin. CONCLUSION: Increased levels of TNFR1, adipokines, chemokines and decrease of IL-4 play important role in the inflammatory process developed in T2DM and decreased renal function. We also suggest that TNFR1 is a strong predictor of renal dysfunction in patients with T2DM.

Discovery and Validation of a Biomarker Model (PRESERVE) Predictive of Renal Outcomes After Liver Transplantation.

BACKGROUND AND AIMS: A high proportion of patients develop chronic kidney disease (CKD) after liver transplantation (LT). We aimed to develop clinical/protein models to predict future glomerular filtration rate (GFR) deterioration in this population. APPROACH AND RESULTS: In independent multicenter discovery (CTOT14) and single-center validation (BUMC) cohorts, we analyzed kidney injury proteins in serum/plasma samples at month 3 after LT in recipients with preserved GFR who demonstrated subsequent GFR deterioration versus preservation by year 1 and year 5 in the BUMC cohort. In CTOT14, we also examined correlations between serial protein levels and GFR over the first year. A month 3 predictive model was constructed from clinical and protein level variables using the CTOT14 cohort (n = 60). Levels of ß-2 microglobulin and CD40 antigen and presence of hepatitis C virus (HCV) infection predicted early (year 1) GFR deterioration (area under the curve [AUC], 0.814). We observed excellent validation of this model (AUC, 0.801) in the BUMC cohort (n = 50) who had both early and late (year 5) GFR deterioration. At an optimal threshold, the model had the following performance characteristics in CTOT14 and BUMC, respectively: accuracy (0.75, 0.8), sensitivity (0.71, 0.67), specificity (0.78, 0.88), positive predictive value (0.74, 0.75), and negative predictive value (0.76, 0.82). In the serial CTOT14 analysis, several proteins, including ß-2 microglobulin and CD40, correlated with GFR changes over the first year. CONCLUSIONS: We have validated a clinical/protein model (PRESERVE) that early after LT can predict future renal deterioration versus preservation with high accuracy. This model may help select recipients at higher risk for subsequent CKD for early, proactive renal sparing strategies.

The miR-145 rs353291 C allele increases susceptibility to atherosclerosis.

Atherosclerosis (AS) is one of the leading causes of death, with variable frequencies in different populations. To this end, we examined whether AS is associated with the miR-145 rs353291 polymorphism and specific rs353291 alleles. The distribution of the rs353291 C allele and CC genotypes was significantly higher in AS patients than in controls. Compared to individuals with the rs353291 TT genotype, carriers of the rs353291 C allele showed a significant increase in the plasma levels of sCD40L, IL-6 and MCP-1 and a decrease in miR-145 expression. After ox-LDL administration, the peripheral blood mononuclear cells (PBMCs) of rs353291 C allele carriers showed significantly increased CD40 and MCP-1 expression compared with those of individuals with the rs353291 TT genotype. These data suggest that the rs353291 C allele may increase susceptibility to atherosclerosis.

No Improvement of Hepatitis B Vaccination Response in Patients Dialysed with a Polymethylmethacrylate Membrane Compared to High-Flux Polysulfone: Results of the HEPADIAL Study.

BACKGROUND: An altered immune response and decreased vaccine response are observed in patients with chronic renal failure. A preliminary study of 15 non-immunised patients, despite appropriate previous hepatitis B vaccination, showed a 60% seroconversion rate after 3 months of dialysis with a polymethylmethacrylate (PMMA) membrane. This response was associated with circulating soluble CD40 (CD40s) decrease, a natural inhibitor of the humoral immune response. The aim of the study is to confirm these results in a randomised study. METHODS: We conducted a multicentre randomised intention-to-treat superiority clinical trial comparing polysulfone and a PMMA membrane in 2 parallel patient groups. The primary end point was the vaccine response rate, as defined by an anti-HBs antibodies titre of >10 IU/L, 1 month after the last vaccination with a double dose of Engerix B20®, performed at weeks 12, 16, 20, and 36. RESULTS: Twenty-five patients were randomised and included in an intention-to-treat analysis. They were dialysed on polysulfone (n = 11) or PMMA (n = 14) for 40 weeks. Fifty percent of the PMMA patients versus 54.5% of the polysulfone patients achieved seroconversion (p = 1.00). The median anti-HBs antibody titre in responders at week 40 was 496 (92-750) versus 395 (43-572) UI/mL for PMMA and polysulfone, respectively (p = 0.46). The median CD40s titre at week 12 was 306 (193-448) versus 491 (281-515) pg/mL (p = 0.21). The CD40s median variation between week 0 and week 12 was 5 (-105 to 90) versus 64 (-63 to 123) pg/mL (p = 0.55). The CD40s level at week 12 in non-responders was slightly inferior to that of the responders: median 193 (168-331) versus 413 (281-512) pg/mL (p = 0.08). CONCLUSION: We did not observe a better vaccine response with the PMMA membrane compared to high-flux polysulfone. The PMMA membrane did not decrease the CD40s more than the polysulfone membrane probably because the titre was previously low in the 2 groups.

Association between CD40 polymorphisms and systemic lupus erythematosus and correlation between soluble CD40 and CD40 ligand levels in the disease: a meta-analysis.

OBJECTIVE: The aim of this study was to systematically review evidence regarding the association between CD40 polymorphisms and systemic lupus erythematosus and between soluble CD40 (sCD40) and CD40 ligand (sCD40L) levels and systemic lupus erythematosus. METHODS: We performed a meta-analysis on the association between CD40 rs4810495, rs1883832, and rs376545 polymorphisms and systemic lupus erythematosus risk and sCD40/sCD40L levels in patients with systemic lupus erythematosus and controls. RESULTS: Fourteen studies were included. Ethnicity-specific meta-analysis indicated a significant association between the T allele of CD40 rs4810485 polymorphism and systemic lupus erythematosus in Europeans (odds ratio = 0.715, 95% confidence interval = 0.641-0.832, p < 0.001) and a trend toward an association between the T allele and systemic lupus erythematosus in Asians (odds ratio = 1.255, 95% confidence interval = 0.978-1.810, p = 0.074). Furthermore, a significant association was reported between systemic lupus erythematosus and the C allele of CD40 rs1883832 polymorphism (odds ratio = 1.235, 95% confidence interval = 1.087-1.405, p = 0.001) and A allele of CD40 rs3765456 polymorphism and systemic lupus erythematosus in Asians (odds ratio = 1.184, 95% confidence interval = 1.040-1.348, p = 0.011). sCD40 and sCD40L levels were significantly higher in SLE than in controls (standardized mean difference = 1.564, 95% confidence interval = 0.256-2.872, p = 0.019 and standardized mean difference = 1.499, 95% confidence interval = 1.031-1.967, p < 0.001, respectively). Stratification based on ethnicity revealed higher sCD40L levels in the systemic lupus erythematosus group among European, Asian, North American, and Arab populations. CONCLUSIONS: Our meta-analyses found associations between CD40 rs4810495, rs1883832, and rs376545 polymorphisms and systemic lupus erythematosus susceptibility and significantly higher sCD40 and sCD40L levels in patients with systemic lupus erythematosus than in controls.

Cytokines and related molecules, and adverse reactions related to platelet concentrate transfusions.

Platelet transfusion is a safe process, but during or after the process the recipient may experience an adverse reaction and occasionally a serious adverse reaction (SAR). Platelet concentrate transfusion may be liable for significant absence of beneficial response. Danger may manifest clinically or biologically; in the latter case, manifestations are frequently an absence of the expected response to the blood component by the recipient. Blood platelets exert roles in inflammation, especially through the immunomodulator complex CD40/CD40L (sCD40L). In this review, we concentrate on the inflammatory potential of platelets and their participation to SARs in transfusion.

Soluble Markers of Antibody Secreting Cell Function as Predictors of Infection Risk in Rheumatoid Arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a systemic autoimmune disease associated with immune dysregulation and increased risk of infections. The presence of autoantibodies and immunoglobulin abnormalities indicates B-cell and antibody-secreting cell (ASC) dysfunction. We hypothesize that soluble factors associated with B-cell and ASC activity are decreased in RA patients and that this is linked to higher susceptibility to infections. METHODS: Using the Johns Hopkins Arthritis Cohort and Biorepository, we contrasted serum protein levels of soluble factors involved in B-cell activation (CD40, CD40L) and B-cell/ASC homing (CXCL10, CXCL11, and CXCL13) or survival (BAFF, APRIL, TACI, and BCMA) in 10 healthy subjects and 23 adult RA patients (aged 24-65 years). We subdivided RA patients into those with (n = 17) and those without infections (n = 6) within a 2-year period. In order to reduce the effect of RA treatment, we only included patients receiving methotrexate monotherapy or no RA treatments at baseline. Soluble serum protein levels of B-cell/ASC factors were quantified by multiplex immunoassays. RESULTS: We identified that (1) serum levels of soluble BCMA, APRIL, CD40, and CD40L were significantly decreased in RA patients relative to healthy individuals; (2) serum soluble BCMA, predominantly released by ASC, correlated with serum concentrations of class-switched immunoglobulins, IgG and IgA; and (3) RA patients with a history of infections had significantly lower soluble BCMA levels compared with healthy donors and with RA patients without infections. CONCLUSIONS: Our study using soluble factors linked to B-cell/ASC activation and survival suggests that there is a paucity of ASC in a subset of RA patients and that this may be linked to altered antibody production and increased risk of infections. Further delineating the link between ASC and infection susceptibility in RA may optimize disease management and provide novel insights into disease pathogenesis that are susceptible to intervention.

Analysis of Genetic Variation in CD40 and CD40L: Relationship with mRNA Relative Expression and Soluble Proteins in Acute Coronary Syndrome.

Acute coronary syndrome (ACS) can be triggered by the presence of inflammatory factors which promote the activation of immune cells by costimulatory molecules such as CD40 and its ligand CD40L. Environmental and genetic factors are involved in the etiology of the ACS. The aim of this study was to explore the gene and protein expression associated with CD40 and CD40L genetic variants in ACS patients from the western Mexican population. A total of 620 individuals from western Mexico were recruited: 320 ACS patients and 300 individuals without a history of ischemic cardiopathy were evaluated. The genotype was determined using TaqMan SNP genotyping assays. CD40 and CD40L expressions at the mRNA level were quantified using TaqMan Gene Expression Assays. Soluble protein isoforms were measured by enzyme-linked immunosorbent assay. We did not find evidence of association between CD40 (rs1883832, rs4810485, and rs11086998) and CD40L (rs3092952 and rs3092920) genetic variants and susceptibility to ACS, although rs1883832 and rs4810485 were significantly associated with high sCD40 plasma levels. Plasma levels of sCD40L can be affected by gender and the clinical spectrum of acute coronary syndrome. Our results do not suggest a functional role of CD40 and CD40L genetic variants in ACS. However, they could reflect the inflammatory process and platelet activation in ACS patients, even when they are under pharmacological therapy. Due to the important roles of the CD40-CD40L system in the pathogenesis of ACS, longitudinal studies are required to determine if soluble levels of CD40 and CD40L could be clinically useful markers of a recurrent cardiovascular event after an ACS.

Inhaled steroids associated with decreased macrophage markers in nonasthmatic individuals with sickle cell disease in a randomized trial.

Inhaled mometasone was shown to improve pain scores and decrease soluble vascular cell adhesion molecule (sVCAM) concentration in a randomized controlled trial of nonasthmatic patients with sickle cell disease. We sought to explore potential changes in systemic inflammation as a mechanism underlying this effect. Serum samples from 41 trial participants (15 placebo- and 26 mometasone-treated) were analyzed using a 92 inflammatory marker panel at baseline and after 8 weeks of mometasone therapy. Individual marker analysis and correlation analysis were conducted. Adjusted for age, the mometasone-treated group decreased the concentration of CXCL9, CXCL11, CD40, IL-10, and IL-18 relative to placebo-treated participants. Hierarchical clustering and correlation analysis identified additional evidence for a decrease in cytokines linking to macrophage signaling and migration. There was no statistically significant change in markers of asthma and allergy, indicating that the improvement was unlikely mediated by modulation of occult reactive airway disease. This analysis of inflammatory markers suggests that decrease in macrophage activity may be involved in the mediation of the clinical benefit seen with use of inhaled mometasone in nonasthmatic patients with sickle cell disease.Trial registration: clinicaltrials.gov identifier: NCT02061202.

The association of CD40 polymorphism (rs1883832C/T) and soluble CD40 with the risk of systemic lupus erythematosus among Egyptian patients.

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex autoimmune disorder of unknown etiology. Considerable evidence supports a genetic basis for susceptibility to SLE. Genetic and functional data suggested the CD40 receptor (CD40) and CD40 ligand (CD40L) as strong candidate genes for SLE. AIM: To investigate whether CD40 gene rs1883832 C/T single-nucleotide polymorphism (SNP) and/or soluble CD40 (sCD40) are associated with SLE in the Egyptian population. SUBJECTS AND METHODS: The study included a hundred SLE patients, and a fifty age- and gender-matched healthy control subjects. CD40 gene rs1883832 C/T genotyping was carried out using restriction fragment length polymorphism (RFLP), while sCD40 levels were measured by ELISA. RESULTS: CD40 rs1883832C/T genotypes (CC, TT, and CT) as well as CD40 alleles (C and T) did not differ between SLE patients and normal control (p = 0.63, 0.37, and 0.31 respectively). Though did not reach statistical significance, carriers of genotype CT had 1.5 times more chance to develop SLE compared to wild homozygous CC genotype carriers (OR 1.44), while carriers of genotype TT had ~ 2 times more chance to have SLE than CC carries (OR 1.96). Accordingly, the carriers of the T allele had ¬ 1.5 times more chance to get SLE compared to the carriers of the C allele (OR 1.4). The serum sCD40 level was significantly higher in SLE patients compared to healthy control (3.4 vs. 0.8 ng/mL, p < 0.001). In SLE patients, using CC as the reference genotype, serum sCD40 level was significantly higher in the carriers of the homozygous genotype TT (3.8 ± 1.3 vs. 2.9 ± 1.9, p = 0.0001), and T allele (3.6 ± 1.4 vs. 3.0 ± 1.5, p = 0.003). Moreover, sCD40 could discriminate SLE patients from normal subjects at a cutoff value of 0.885 ng/mL with 98% sensitivity and 96% specificity (AUC = 0.999, p < 0.001). CONCLUSIONS: The study did not prove CD40 gene (rs1883832 C/T) polymorphism as a clear risk factor of SLE in this cohort of Egyptian patients, though it was highly likely associated with the carriers of T allele. In the same context, significant high sCD40 levels were observed in the T allele carriers.

High Serum sCD40 and a Distinct Colonic T Cell Profile in Ulcerative Colitis Associated With Primary Sclerosing Cholangitis.

BACKGROUND AND AIMS: There is a strong association between primary sclerosing cholangitis [PSC] and ulcerative colitis [UC], but the immunological link between the two diseases is obscure. We compared serum cytokine profiles of patients with PSC-UC and UC, and investigated a number of selected cytokines in colonic biopsy samples. We also assessed the presence and activation of T cells in peripheral blood and colonic mucosa. METHODS: Serum samples from 22 patients with PSC-UC, 28 patients with UC, and 19 controls were analysed by a proximity extension assay including 92 inflammatory cytokines. Biopsies from caecum, sigmoid colon, and rectum were collected from the same patients. Quantitative analysis for IFN-γ, IL-2, IL-4, IL-5, IL-13, IL-17A/ E/F, IL-21, IL-22, IL-23, and IL-27 was carried out on tissue homogenates. T cell phenotype was evaluated by flow cytometry. RESULTS: By multivariate analysis we identified a cluster of serum cytokines with higher levels in PSC-UC, and sCD40 in particular was strongly associated with this patient group. In contrast, colonic cytokines were only modestly increased in PSC-UC, whereas several Th1-, Th2-, and Th17-associated cytokines were increased in UC. Patients with PSC-UC had increased colonic levels of CXCR3-positive CD8+ T cells but fewer CD25-positive CD4+ T cells. An increased CRTH2/CXCR3-quote indicated a predominance of Th-2 type CD4+ T cells in UC patients. CONCLUSIONS: Our study reveals different cytokine profiles and T cell profiles in PSC-UC and UC, with higher systemic levels of cytokines in PSC-UC, and a more pronounced colonic inflammation in UC. Serum sCD40 could potentially be investigated as a marker for PSC in UC.

The CD40 rs1883832 Polymorphism Affects Sepsis Susceptibility and sCD40L Levels.

Sepsis is a severe and progressive disease characterized by systemic inflammatory response syndrome (SIRS). CD40 serves as a vital link between immune response and inflammation. This study was designed to investigate the potential association between a functional single-nucleotide polymorphism (SNP) of CD40 (rs1883832) and susceptibility to sepsis. We first performed a case-control study to explore the relationship between the CD40 rs1883832 polymorphism and sepsis. CD40 mRNA expression and protein expression were determined by real-time PCR and western blotting, respectively, in peripheral blood mononuclear cells (PBMCs) from sepsis patients and healthy controls. The plasma sCD40L levels in the two groups were measured by ELISA. The results showed that the frequencies of the TT genotype and the CD40 rs1883832 T allele were significantly higher in sepsis patients than in healthy controls. Plasma sCD40L levels were also significantly increased in sepsis patients. In addition, TT genotype carriers among sepsis patients displayed the highest CD40 expression at both the mRNA and protein levels, accompanied by the highest plasma sCD40L concentrations. In conclusion, the CD40 rs1883832 T allele acts as a risk factor for increased susceptibility to sepsis and may be involved in the process of sepsis through regulation of CD40 expression and plasma sCD40L levels.

Effect of abnormal activated B cells in patients with ankylosing spondylitis and its molecular mechanism.

OBJECTIVE: Ankylosing spondylitis (AS) is a common clinical autoimmune disease, the pathogenesis of which, however, is not yet elucidated. In this study, we aim to explore the effect of B cells in the development and progression of AS and its underlying mechanism. PATIENTS AND METHODS: B cells were isolated from peripheral blood of AS patients and normal controls. Surface expression of CD40 in B cells was detected by flow cytometry. Expressions of downstream genes in MAPK pathway were detected by Western blot. Moreover, IL-10 expressions in peripheral blood of AS patients and normal controls were detected by ELISA. RESULTS: No difference was found in the surface expression of CD40 in B cells between AS patients and normal controls. However, CD40 expression was inhibited after B cells in peripheral blood were specifically stimulated by lipopolysaccharide (LPS) in vitro. Abnormal activated B cells, dysregulated p38 expressions and decreased serum expressions of IL-10 were also observed in AS patients. CONCLUSIONS: Abnormal surface expression of CD40 inn B cells of AS patients may lead to abnormal activation of B cells, thereby interfering the p38 MAPK pathway and reducing the IL-10 secretion.

Switching from abacavir to tenofovir disoproxil fumarate is associated with rises in soluble glycoprotein VI, suggesting changes in platelet-collagen interactions.

OBJECTIVES: Altered platelet function has been proposed as an underlying mechanism to explain increased risk of myocardial infarction in people living with HIV associated with use of the nucleoside reverse transcriptase inhibitor abacavir (ABC). We aimed to examine changes in platelet biomarkers in people living with HIV switching from ABC. METHODS: In a prospective, 48-week substudy of virally suppressed HIV-1-positive subjects randomized to remain on ABC/lamivudine (ABC/3TC) or switch to tenofovir disoproxil fumarate/emtricitabine, we measured soluble glycoprotein VI (sGPVI), soluble P-selectin, soluble CD40 ligand and von Willebrand factor in plasma collected over time and assessed differences using mixed effect models. RESULTS: Of 312 randomized participants, 310 were included in the analysis. Mean (SD) age 46.4 (9.3) years, 262 (85%) men and 201 (65%) white. At baseline, there was no significant between-group difference in sGPVI [tenofovir disoproxil fumarate/emtricitabine 3.75 (0.25) versus ABC/3TC 3.61 (0.22) ng/ml, P = 0.69]. Greater increases in sGPVI from baseline to week 48 occurred in those switched from ABC/3TC (effect size +0.57 ng/ml; 95% confidence interval, 0.2-0.94; P = 0.003). There was no significant baseline difference or change overtime in soluble P-selectin, soluble CD40 ligand or von Willebrand factor between groups. CONCLUSION: The significant increases in sGPVI that occur with a switch from ABC/3TC are suggestive of changes in platelet function centred on platelet/collagen interactions and potentially represent an underlying mechanism to explain increased risk of myocardial infarction with ABC.