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Background: Locally advanced triple-negative breast cancer (TNBC) represents a public health problem in Brazil. Its standard treatment consists of neoadjuvant chemotherapy (NAC)., Methods: This was a longitudinal study with follow-up performed between the years 2015 and 2017. Thirty women with locally advanced TNBC submitted to NAC, and 30 healthy were included. Peripheral blood samples were collected before NAC (Pre-NAC) and after NAC (Post-NAC)., Results: Patients with TNBC had elevated levels of CD28+ T, FAS+ T, CTLA4+ T, PD1+ T, CD28+CD4+ T, PD1+CD4+ T and CD8+ T and PD1+ CD8+ T cells compared to controls (p < 0.05). Patients with pathological complete response (pCR) had low FAS+ T cells, FAS+CD4+ T cells, and PD1+CD8+ T cells compared to the non-pCR (p < 0.05). Significant differences were observed in the levels of CD28+ T cells, FAS+ T and PD1+ T, CD4+ T, CD28+CD4+ T, FAS+CD4+ T, PD1+CD4+ T, CD8+ T, and PD1+CD8+ T cells between Pre-NAC and Post-NAC groups (p < 0.05)., Conclusion: Alterations in the circulating FAS+CD4+ T and PD1+CD8+ T cell levels Pre-NAC are associated with pCR, suggesting potential predictive biomarkers of NAC response in TNBC. The largest changes in the cellular immune response profile Post-NAC showed that chemotherapy treatment can modulate the immune response and that it is associated with prognosis in TNBC., (© 2024 Wiley Periodicals LLC.)

Objective To investigate the levels of costimulator molecules CD28, CD152/CTLA4, PD-1 and NK cells in peripheral blood of patients with pulmonary tuberculosis (PTB), and to explore the activation of T cell subsets and function of NK cell in PTB patients, as well as the role of T cell costimulatory signaling molecules in the pathogenesis of PTB. Methods Thirty-two PTB patients (PTB group) and 15 health examiners (control group) were recruited.The expression of CD28 and CD152 on peripheral blood T lymphocytes was detected by flow cytometry. The relationship between the two group was analyzed using receiver operating characteristic (ROC) curves. The expression of PD-1 on regulatory T cells (Tregs) and the proportion of NK cells in peripheral blood were detected by flow cytometry. Results Compared with the control group, the proportions of CD8 + CD28 + T cells and CD8 + CD152 + T cells were significantly lower in the PTB group.The ROC curve showed that the variable CD8 + CD152 + T cell proportion had some predictive value in PTB (AUC=0.800, CI=0.664-0.936). The proportions of CD4 + CD28 + T cells and CD4 + CD152 + T cells had no predictive value. There was a positive correlation between CD4 + CD28 + T cells and CD8 + CD28 + T cells in PTB group (r=0.563). Compared with the control group, the proportion of NK cells was significantly reduced in the PTB group. Conclusion The proportions of CD8 + CD152 + T cells, CD8 + CD28 + T cells, and NK cells significantly reduced in PTB patients.

Background: There is a need to identify vascular and geroscience-relevant markers and mediators that can physiologically link ageing to vascular disease. There is evidence of specific T cell subsets, all influenced by age, that exert positive and negative effects on vascular health. CD31+, termed angiogenic T cells, have been linked to vascular repair whereas CD28null, termed senescent T cells, display pro-inflammatory and cytotoxic effector functions., Objective: This study sought to determine the combined influence of increasing age and frailty status on these circulating CD31+ and CD28null T cell subsets., Methods: This cross-sectional study recruited four different cohorts of men and women; young (20-30 years, n=22), older (65-75 years, n=17), robust non-frail (76+ years, n=17), and frail (76+ years, n=15) adults. Frailty was determined using the Fried Frailty method. T cell subsets were determined by whole blood flow cytometry based on the expression of CD3, CD4, CD8, CD31 and CD28. Cognitive impairment (CI) was measured via the Montreal Cognitive Assessment test., Results: Whether expressed as circulating counts or as a % of total T cells, there was a progressive decrease (p<0.05) in CD31+ T cells with increasing age but paradoxically higher values (p<0.05) in the frail compared to the robust non-frail group. These changes were similar in the CD4+ and CD8+ fractions. CD28null T cells were considerably higher (p<0.05) in the frail compared to the robust non-frail group, including in the CD8+ (47% vs 29%, p<0.05) and CD4+ (4% vs 1%, p<0.05) fractions. CD28null T cell percentage was also higher (p<0.05) in those with moderate CI compared to mild CI and normal function., Conclusion: CD8+CD28null T cells are considerably elevated in frailty and with cognitive impairment and may serve as a useful target for intervention. Currently, the utility of CD31+ T cells as an ageing biomarker may be confined to healthy ageing cohorts., Competing Interests: On behalf of all authors, the corresponding author declares that there is no conflicts of interest.

Purpose: Initial military training (IMT) is a transitionary period wherein immune function may be suppressed and infection risk heightened due to physical and psychological stress, communal living, and sleep deprivation. This study characterized changes in biomarkers of innate and adaptive immune function, and potential modulators of those changes, in military recruits during IMT., Methods: Peripheral leukocyte distribution and mitogen-stimulated cytokine profiles were measured in fasted blood samples, Epstein-Barr (EBV), varicella zoster (VZV), and herpes simplex 1 (HSV1) DNA was measured in saliva by quantitative polymerase chain reaction as an indicator of latent herpesvirus reactivation, and diet quality was determined using the healthy eating index measured by food frequency questionnaire in 61 US Army recruits (97% male) at the beginning (PRE) and end (POST) of 22-wk IMT., Results: Lymphocytes and terminally differentiated cluster of differentiation (CD)4+ and CD8+ T cells increased PRE to POST, whereas granulocytes, monocytes, effector memory CD4+ and CD8+ T cells, and central memory CD8+ T cells decreased ( P ≤ 0.02). Cytokine responses to anti-CD3/CD28 stimulation were higher POST compared with PRE, whereas cytokine responses to lipopolysaccharide stimulation were generally blunted ( P < 0.05). Prevalence of EBV reactivation was higher at POST ( P = 0.04), but neither VZV nor HSV1 reactivation was observed. Diet quality improvements were correlated with CD8+ cell maturation and blunted proinflammatory cytokine responses to anti-CD3/CD28 stimulation., Conclusions: Lymphocytosis, maturation of T-cell subsets, and increased T-cell reactivity were evident POST compared with PRE IMT. Although EBV reactivation was more prevalent at POST, no evidence of VZV or HSV1 reactivation, which are more common during severe stress, was observed. Findings suggest increases in the incidence of EBV reactivation were likely appropriately controlled by recruits and immune-competence was not compromised at the end of IMT., (Copyright © 2023 Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a "œwork of the United States Government"œ for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.)

This study aimed to investigate the impact of a 16-week dance-based aerobic exercise program on lymphocyte function in healthy and type 2 diabetes mellitus (T2DM) women. We enrolled 23 women: 11 with T2DM and 12 non-diabetic controls. Initially, we performed anthropometry and body composition measurements, afterwards, plasma levels of C-reactive protein, lipids, and glucose were determined. We used flow cytometry to measure the CD25 and CD28 expression in circulating lymphocytes, T-regulatory (Treg) cell percentage, lymphocyte proliferation, and cytokines released by cultured lymphocytes. The T2DM group had a lower proportion of CD28+ cells and a higher percentage of Treg lymphocytes and proliferative capacity at the baseline compared with the control group. After 16 weeks of the program, differences in lymphocytes between the T2DM and the control groups disappeared. The dance program promoted IL-10 increase in both groups. We found decreased IL-4, IL-2, and IL-6 secretion in lymphocytes from the control group and increased IL-17 secretion and IL-10/IL-17 ratio in the T2DM group after the program. The program promoted marked changes in lymphocytes in diabetic women, leading to a balance between the different profiles., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Few studies have illuminated the genetic role of T cell costimulatory molecule CD28/CD80/CTLA4 variants in diabetic kidney disease (DKD) susceptibility. We aimed to investigate the causal role of genetic polymorphisms in CD28/CD80/CTLA4 with DKD susceptibility in patients with T2DM. A total of 3253 patients with T2DM were recruited for genotyping: including 204 DKD patients and 371 controls in stage 1 and 819 DKD patients and 563 controls in stage 2; besides, 1296 T2DM patients were selected for the analysis of association between loci and DKD-related traits. A subset of 227 T2DM patients (118 patients with DKD and 109 patients without DKD) from the total population above were selected to assess serum soluble CD28 (sCD28) levels. Then, we performed a candidate gene association study to identify single-nucleotide polymorphisms (SNPs) associated with DKD susceptibility and further used those SNPs to perform Mendelian randomization analyses of serum sCD28 level and DKD susceptibility. Under additive genetic models, CD28 -rs3116494 (OR = 1.29 [95% CI 1.11, 1.51], P = 0.0011) and CD80 -rs3850890 (OR = 1.16 [95% CI 1.02, 1.31], P = 0.0283) were associated with DKD susceptibility adjusted for age, gender, body mass index (BMI), duration of diabetes, and HbA1c. CD28 -rs3116494 was associated with serum sCD28 level ( β = 0.26 [95% CI 0.08, 0.44], P = 0.0043). The Mendelian randomization analysis showed that CD28 -rs3116494 played a causal role in DKD by influencing serum sCD28 levels ( β = 1.15 [95% CI 0.46, 1.83], P = 0.0010). In conclusion, we identified that two novel SNPs, CD28 -rs3116494 and CD80 -rs3850890, were associated with DKD susceptibility. Using the Mendelian randomization analysis, our study provided evidence for a causal relationship between serum CD28 levels and DKD with T2DM in the Chinese population., Competing Interests: The authors declare that they have no relevant financial interests., (Copyright © 2021 Yangyang Li et al.)

Heat-inactivation of sera is used to reduce possible disturbing effects of complement factors in cell-culture experiments, but it is controversially discussed whether this procedure is appropriate or could be neglected. Here, we report a strong impact of heat-inactivation of human sera on the activation and effector functions of human CD4+ T cells. While T cells cultured with native sera were characterized by a higher proliferation rate and higher expression of CD28, heat-inactivated sera shaped T cells towards on-blast formation, higher cytokine secretion (interferon γ, tumor necrosis factor, and interleukin-17), stronger CD69 and PD-1 expression, and increased metabolic activity. Heat-inactivated sera contained reduced amounts of complement factors and regulators like C1 inhibitor, but increased concentrations of circulating immune complexes. Substitution of C1 inhibitor reduced the beneficial effect of heat-inactivation in terms of cytokine release, whereas surface-molecule expression was affected by the addition of complex forming anti-C1q antibody. Our data clearly demonstrate a beneficial effect of heat-inactivation of human sera for T cell experiments but indicate that beside complement regulators and immune complexes other components might be relevant. Beyond that, this study further underpins the strong impact of the complement system on T cell function.

Introduction: Primary blast affects the kidneys due to direct shock wave damage and the production of proinflammatory cytokines without effective treatment. CD28 has been reported to be involved in regulating T cell activation and secretion of inflammatory cytokines. The aim of this study was to investigate the influence of primary blast on the kidney and the effect of CD28 in mice., Methods: A mouse model of primary blast-induced kidney injury was established using a custom-made explosive device. The severity of kidney injury was investigated by H&E staining. ELISA was applied to study serum inflammation factors' expression. Western blot assays were used to analyse the primary blast-induced inflammatory factors' expression in the kidney. Immunofluorescence analysis was used to examine the PI3K/Akt signalling pathway., Results: Histological examination demonstrated that compared with the primary blast group, CD28 deficiency caused a significant decrease in the severity of the primary blast-induced renal injury. Moreover, ELISA and western blotting revealed that CD28 deficiency significantly reduced the levels of interleukin (IL)-1β, IL-4 and IL-6, and increased the IL-10 level (p<0.05). Finally, immunofluorescence analysis indicated that PI3K/Akt expression also changed., Conclusions: CD28 deficiency had protective effects on primary blast-induced kidney injury via the PI3K/Akt signalling pathway. These findings improve the knowledge on primary blast injury and provide theoretical basis for primary blast injury treatment., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: T-cell activation pathways have been proposed as trigger mechanisms in the pathogenesis of rheumatoid arthritis (RA). CD28 and CTLA-4 play major roles in regulating the stimulatory and inhibitory co-signals in T cells., Objective: To analyze the association between soluble and surface expression of CD28 and CTLA-4 with the clinical parameters of RA patients., Methods: A total of 35 RA patients classified as early RA (n = 14), chronic RA (n = 14), and untreated RA (n = 7), as well as 7 age- and sex-matched control subjects (CS) were included. Surface expression of CD28 and CTLA-4 on T cells was evaluated by flow cytometry. Soluble levels of CD28 (sCD28), CTLA-4 (sCTLA-4), and anti-CCP antibodies were measured by ELISA., Results: A significant lower percentage of CD8 + T cells positive to CD28 (CS = 64.9% vs RA = 42.7%, P = .04), and diminished surface expression of CD28 (CS: MFI = 122.9 vs RA: MFI = 33.1, P = .006), were found in chronic RA patients compared to CS. Higher sCD28 were observed in early RA patients compared with chronic RA patients (P < .05). sCTLA-4 was found increased in untreated RA patients compared to early RA patients (P < .05). sCD28 concentration correlated with anti-CCP levels (rho = -0.12; P = .032). The soluble and surface expressions of CTLA-4 were not associated with RA clinical parameters., Conclusions: In RA, the percentage of CD8 + CD28+ T cells decreases and expresses fewer membrane CD28 than CS. sCD28 levels are lower in chronic RA and are associated negatively with anti-CCP levels. sCTLA 4 levels are lower in early RA patients than in untreated RA patients., (© 2020 The Authors. Journal of Clinical Laboratory Analysis Published by Wiley Periodicals, Inc.)

Cytokine release syndrome (CRS) is a serious and potentially life-threatening complication typically associated with biological drug products. Pre-clinical testing in vitro and in vivo studies using non-human primates had failed to reliably predict CRS. To determine if bone marrow-thymus-liver (BLT) humanized mice with a fully engrafted human immune system or a CD34-humanized mouse model could predict CRS, we tested an anti-CD28 monoclonal antibody (mAb) similar to TGN1412. This TGN1412 analogue (TGN1412A) was initially tested in vitro and found to produce significant dose-dependent increases in cytokine production. For in vivo studies, adalimumab, an anti-tumor necrosis factor-alpha antibody known not to cause CRS, served as a negative control. We evaluated immune cell activation and cytokine expression in three independent experiments. In BLT humanized mice, significant increases in levels of human cytokines were identified in animals treated with anti-CD28 mAb. As expected, CD28+ cell detection was strongly reduced in the anti-CD28 treated group. Increased T cell activation was also observed. The control group did not show reductions in CD28+ T-cells and did not experience increased cytokine levels. Responses by CD34-humanized mice showed no significant differences between adalimumab and anti-CD28 treatment at doses used to test BLT-humanized mice. These results suggest that the TGN1412A produces similar results in vitro to the original TGN1412 monoclonal antibody. The BLT immune humanized mice but not the CD34 humanized mice produce both robust and specific cytokine responses and may represent a pre-clinical model to identify CRS., (Copyright © 2019. Published by Elsevier Inc.)

Objectives: To determine whether the CD4+CD28null T-cells subpopulation predicts the occurrence of damage in SLE., Methods: This longitudinal study was conducted in consecutive SLE patients seen every six months in our Rheumatology Department since 2012. Patients in whom CD4+CD28null T-cells had been measured and who had at least one subsequent visit were included in the study. Survival analyses (univariable and multivariable Cox-regression models) were performed to determine the risk of overall and domain damage (as per the SLICC Damage Index - SDI) as a function of the frequency of this T-cell subpopulation. The multivariable model was adjusted for pertinent confounders. All analyses were performed using SPSS 21.0., Results: One hundred and nineteen patients were evaluated; their mean (SD) age was 43.5 (11.9) years, 113 (95.0%) were female. Disease duration was 7.8 (7.0) years, the SLEDAI 5.3 (4.1) and the SDI 1.0 (1.4). The percentage of CD4+CD28null T-cells was 17.4 (14.0). The mean follow-up was 2.1 (0.8) years, and the mean number of visits per patient 3.5 (1.1). Forty-six (38.7%) patients increase at least one SDI point. In the univariable and multivariable analyses, the percentage of CD4+CD28null predicted the occurrence of lung damage [HR: 1.042 (CI95%: 1.001-1.085); p=0.047 and HR: 1.099 (CI95%1.020-1.184); p=0.013, respectively] but neither the total SDI score nor all other SDI domain scores were predicted by the percentage of CD4+CD28null cells., Conclusions: In SLE patients, CD4+CD28null T-cells predict the occurrence of new lung damage, independently of other risk factors but not of overall damage or damage on other domains.

Aging is associated with elevated cardiovascular disease risk. As a result of aging, endothelial dysfunction develops, partly due to a reduction in vascular regenerative ability. CD31 + T cells (angiogenic T cells; T ANG ) possess highly angiogenic capabilities; however, these cells are significantly reduced in older populations. In addition, older populations possess significantly higher senescent and highly differentiated T-cell levels in circulation, and these are reported to be highly exercise responsive. We investigated whether older adults display greater levels of circulating senescent (CD28 null ) T ANG cells and whether these cells were more exercise responsive than CD28 + T ANG cells. Young (18-25 years; n = 9) and older (60-75 years; n = 10) healthy men undertook a 30-min cycling bout at 70% V˙O 2 peak, with circulating T ANG cells (CD3 +  CD31 +  CD28 +/null ; including CD4 + and CD8 + subsets) measured preexercise, postexercise, and 1 h post exercise by flow cytometry. Older adults displayed reduced basal levels of T ANG cells (mean ± SEM: 410 ± 81 vs. 784 ± 118 cells·μL, P = 0.017), despite a greater proportion of these cells being CD28 null (26.26 ± 5.08 vs. 13.36 ± 2.62%, P = 0.044). Exercise significantly increased the circulating number of T ANG cells in both young and older men. However, in older men alone, exercise preferentially mobilized CD28 null CD8 + T ANG cells compared with CD28 + T ANG cells (time × phenotype interaction: P = 0.022; Δ74 ± 29 vs. Δ27 ± 15 cells·μL, P = 0.059), with no such difference observed between these phenotypes in the young population. In conclusion, this is the first study to demonstrate that despite observing lower circulating numbers of T ANG cells, older adults display greater levels of senescent T ANG cells in comparison with younger individuals, and these cells are more exercise responsive than CD28 + T ANG cells. Lower number of circulating T ANG and greater levels of senescent-associated CD28 null T ANG may contribute to greater CVD risk with advancing age., (© 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Background/aim: The balance of blood CD8 + CD28 + /CD8 + CD28 - T cells has been verified to be vital for patients with ulcerative colitis (UC), but their role in inflammatory bowel disease (IBD) remains unknown. This investigation aimed to evaluate the efficiency of the balance in predicting the active stage in IBD patients., Methods: Fifty-three IBD subjects, including 31 UC and 22 Crohn's disease (CD) patients, were enrolled, and their peripheral blood CD8 + CD28 + and CD8 + CD28 - T cell levels were tested using flow cytometry. The risk factors related to prognosis were compared between UC and CD patients. A 1-year follow-up was performed for all the IBD patients, and the CD8 + T cells and their ratio were compared at the 3rd, 6th, 9th, and 12th months during follow-up. The sensitivity and specificity of the CD8 + T cell level and balance were analyzed through receiver operator characteristic (ROC) curves. The cumulative remission lasting rates (CRLRs) under the different factors were analyzed using the Kaplan-Meier method., Results: Higher prescription rates of immunosuppressants, steroids, probiotics, and biological agents (BAs) were found in CD subjects in comparison to UC subjects (P=0.005, 0.024, 0.034, and 0.001), as was a higher active rate during follow-up (95.5% of CD patients vs 67.7% of UC patients, P=0.035). The CD8 + CD28 + T cell level and the CD8 + CD28 + /CD8 + CD28 - T cell ratio were significantly higher in UC patients than in CD patients, but the reverse was true for CD8 + CD28 - T cells during follow-up at the 9th and 12th month (all P<0.05). The diagnostic models of the initial CD8 + CD28 + and CD8 + CD28 - T cell numbers and the CD8 + CD28 + /CD8 + CD28 - T cell ratio in predicting the active stage were found to be significant, with areas under the curves (AUCs) of 0.883, 0.098, and 0.913 for UC subjects (with 95% CI: 0.709-0.940, 0.009-0.188, and 0.842-1.003; P=0.001, 0.00, and 0.000) and 0.812, 0.078, and 0.898 for CD subjects (with 95% CI: 0.683-0.957, 0.003-0.158, and 0.837-0.998; P=0.003, 0.00, and 0.000). The cut-off values showed that when the ratios were 1.30 for UC and 1.22 for CD patients, the best sensitivity and specificity were observed, with 91.6% and 89.0% for UC and 88.5% and 85.1% for CD, respectively. The CRLRs were significantly higher in female, non-BA-treated, non-surgical IBD subjects when compared to male, BA-treated, surgical subjects (P=0.031, 0.000, and 0.000). The number of CD8 + CD28 + and CD8 + CD28 - T cells and the CD8 + CD28 + /CD8 + CD28 - T cell ratio were correlated with BA treatment and surgery (all P<0.05)., Conclusion: The CD8 + CD28 + /CD8 + CD28 - T cell balance, expected to be a novel immunologic marker, presented a satisfactory efficiency with high sensitivity and specificity in predicting the active stage in UC and CD patients, and the balance was closely related to the use of BAs and surgery., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Polypoidal choroidal vasculopathy (PCV) and neovascular age-related macular degeneration (AMD) are prevalent age-related diseases characterized by exudative changes in the macula. Although they share anatomical and clinical similarities, they are also distinctly characterized by their own features, e.g. vascular abnormalities in PCV and drusen-mediated progression in neovascular AMD. PCV remains etiologically uncharacterized, and ongoing discussion is whether PCV and neovascular AMD share the same etiology or constitute two substantially different diseases. In this study, we investigated T-cell differentiation and aging profile in human patients with PCV, patients with neovascular AMD, and age-matched healthy control individuals. Fresh venous blood was prepared for flow cytometry to investigate CD4 + and CD8 + T-cell differentiation (naïve, central memory, effector memory, effector memory CD45ra + ), loss of differentiation markers CD27 and CD28, and expression of aging marker CD56. Patients with PCV were similar to the healthy controls in all aspects. In patients with neovascular AMD we found significantly accelerated T-cell differentiation (more CD28 - CD27 - cells) and aging (more CD56 + cells) in the CD8 + T-cell compartment. These findings suggest that PCV and neovascular AMD are etiologically different in terms of T cell immunity, and that neovascular AMD is associated with T-cell immunosenescence.

Women are living longer than men and it seems that one of the reasons could be better immune system of females. In Poland, contrary to many European countries, women retire earlier than men, namely at 60 and 65, respectively. We asked the question how the gender and labour status were interconnected with some immunological parameters included in the so called immune risk profile (IRP), such as CD4+/CD8+ ratio, percentage of CD8+CD28-, and NK, and the level of circulating cytokines. A total of 92 men and 100 women past the retirement age, namely 65-74 years old, still working or not, were examined. We have found statistically significant lower percentage of CD8+CD28- cells and non-statistically significant higher CD4+/CD8+ ratio in women, whereas the percentage of NK was higher in men. Moreover, the percentage of CD8+CD28- cells was negatively correlated with the CD4+/CD8+ ratio and the concentration of IL8 was positively correlated with the concentration of IL10 both in men and women. In men, the level of IL10 was higher than in women. Altogether, we found that gender, but not labour status, influences immunosenescence of the examined population of 65-74 years old Polish people.

The introduction of anti-calcineurin-based therapies has led to an increase in the one-year survival as well as graft function rates in patients undergoing solid organ transplantation (SOT). Nonetheless, early cellular acute rejection (EAR) incidence still remains a major challenge that irrevocably heads to poor outcomes. The mechanisms underlying CD4 T cell activation in SOT are still under research. In this sense, CD28 co-stimulatory molecule plays a pivotal role triggering CD4 T cell activation as well as survival maintenance. Previous own studies stated the role that CD4 + CD28 + circulating T lymphocytes plays before and during EAR episodes. We assessed the percentage as well as the absolute number of CD28 molecules on CD4 + T cells as predictive surrogate biomarker of EAR in a prospective cohort of liver and kidney transplant recipients. Quantitative analysis of CD28 was carried out on whole peripheral blood samples by flow cytometry. Decreased pre-transplant expression of CD28 was associated with EAR in both study groups. Furthermore, the expression of CD28 within the rejected group, experimented an up-regulation upon transplantation. These preliminary results suggest that patients undergoing liver or kidney transplant can be stratified at high risk of EAR according to their CD28 molecule expression on peripheral CD4 + T lymphocytes., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: CD28 is a 44 kDa glycoprotein that is important in initiating T-cell responses and that results in increased T-cell proliferation and interleukin-2 production. This study estimated the serum CD28 levels in patients with asthma and evaluated the effect of inhaled corticosteroids (ICS) on the levels of CD28, the peak expiratory flow rate (PEFR), and quality of life (QOL)., Methods: This prospective, open-label, observational study enrolled 40 adult patients with asthma of mild-to-moderate severity who were started on ICS and 40 healthy controls. Patients with bronchial asthma were evaluated for their serum CD28 level and QOL by using Mini Asthma Quality of Life Questionnaire scores, severity of symptoms, and PEFR at baseline and after 4 weeks., Results: The mean (standard deviation [SD]) serum CD28 concentration in patients with asthma was 107 ± 4.98 ng/mL, which was significantly elevated (p < 0.01) compared with the healthy individuals (37.67 ± 18.28 ng/mL). ICS treatment for 4 weeks reduced the mean (SD) serum CD28 levels to 40.9 ± 2.82 ng/mL. PEFR increased significantly, from 190.75 ± 10.55 to 263 ± 10.69 L/min (p < 0.01) after 4 weeks. Similarly, the mean (SD) Mini Asthma Quality of Life Questionnaire scores significantly increased, from 36.90 ± 10.31 on day 0 to 70.63 ± 11.56 on day 28 after ICS therapy (p < 0.01). A negative correlation between the elevations of serum CD28 levels was seen with QOL., Conclusion: The serum CD28 concentration, a marker of inflammation, is increased in bronchial asthma and reduced by ICS therapy. ICS also improved QOL scores and objective clinical outcomes in patients with asthma.

Atrial fibrillation (AF) represents the most common cardiac arrhythmia. Especially in patients with chronic heart failure (CHF) the development of AF represents a severe complication resulting in haemodynamic deterioration. While pro-inflammatory cytokines proved to have a pivotal role in the development and progression of both AF and CHF, less attention has been paid to the cellular immunity. Therefore we prospectively enrolled 112 patients with CHF and performed fluorescein-activated cell sorting (FACS). Patients were stratified in two subgroups according to patients presenting with AF (n=56) and patients free of AF (n=56). Comparing AF to non-AF patients we found a significantly lower fraction of regulatory T cells (p<0.001) in patients presenting with AF. However there was a higher fraction of CD4 + cells (p=0.007) and more specifically a significantly higher number of cytotoxic T cells characterised by the loss of CD28 within CD4 T cells (CD4 + CD28 null ; p=0.035) in individuals with AF. After a mean follow-up time of 4.5 years 32 (28.6 %) patients died due to cardiovascular causes. CD4 + CD28 null cells were significantly associated with cardiovascular mortality in patients presenting with AF, with an adjusted HR per one standard deviation (1-SD) of 1.59 (95 % CI 1.13-2.24; p=0.008), but not in patients free of AF with an adjusted HR per 1-SD of 1.27 (95 % CI 0.86-1.87; p=0.216). We found that the fraction of CD4 + CD28 null cells proved to be predictive on outcome in CHF-patients presenting with AF. Our results might indicate a potential role of CD4 + CD28 null cells in the pathogenesis of AF which needs to be confirmed in future studies.

Background: Acute rejection (AR) remains a significant cause of graft loss. Better approaches to predict AR are being investigated. Surface CD28 protein is essential for T-cell proliferation and survival as well as cytokine production., Patients and Methods: Pretransplant CD4 + CD28 + peripheral T cells were examined in 30 liver recipients (LRs) and 31 kidney recipients (KRs) by flow cytometry., Results: Pretransplant CD4 + CD28 + T cells in LRs were significantly lower in rejectors than nonrejectors (P = .002). Furthermore, the total number of CD28 molecules per cell in LRs (P = .02) as well as KRs (P = .047) was significantly lower in rejectors than nonrejectors. The healthy group did not display differences when compared with patients with end-stage liver disease or renal failure; however, stratification analysis displayed higher levels of CD4 + CD28 + when compared with rejected LRs (P = .04) but not KRs. CD28 levels <41.94% were able to discriminate LRs at high risk of AR (P = .003). Similarly, a total number of CD28 molecules ≤8359 (P = .031) in LRs and ≤7669 (P = .046) in KRs correlated with high risk of AR., Conclusion: The preliminary results presented herein exhibit a fast and noninvasive method that assists clinicians to prevent AR by monitoring CD4 + CD28 + peripheral T cells., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Corticosteroid resistance is a major barrier to effective treatment of COPD. We have shown that the resistance is associated with decreased expression of glucocorticoid receptor (GCR) by senescent CD28nullCD8+ pro-inflammatory lymphocytes in peripheral blood of COPD patients. GCR must be bound to molecular chaperones heat shock proteins (Hsp) 70 and Hsp90 to acquire a high-affinity steroid binding conformation, and traffic to the nucleus. We hypothesized a loss of Hsp70/90 from these lymphocytes may further contribute to steroid resistance in COPD., Methods: Blood was collected from COPD (n = 10) and aged-matched controls (n = 10). To assess response to steroids, cytotoxic mediators, intracellular pro-inflammatory cytokines, CD28, GCR, Hsp70 and Hsp90 were determined in T and NKT-like cells in the presence of ± 10 μM prednisolone and 2.5 ng/mL cyclosporine A (binds to GCR-Hsp70/90 complex) using flow cytometry, western blot and fluorescence microscopy., Results: A loss of expression of Hsp90 and GCR from CD28null CD8+ T and NKT-like cells in COPD was noted (Hsp70 unchanged). Loss of Hsp90 expression correlated with the percentage of CD28null CD8+ T and NKT-like cells producing IFNγ or TNFα in all subjects (eg, COPD: R = -0.763, p = 0.007 for T-cell IFNγ). Up-regulation of Hsp90 and associated decrease in pro-inflammatory cytokine production was found in CD28nullCD8+ T and NKT-like cells in the presence of 10 μM prednisolone and 2.5 ng/mL cyclosporine A., Conclusions: Loss of Hsp90 from cytotoxic/pro-inflammatory CD28nullCD8+ T and NKT-like cells could contribute to steroid resistance in COPD. Combination prednisolone and low-dose cyclosporine A therapy inhibits these pro-inflammatory cells and may reduce systemic inflammation in COPD.

Renal cell carcinoma (RCC) is an immunogenic and proangiogenic cancer. Although antivascular endothelial growth factor (VEGF) therapies achieve impressive responses in some patients, many tumors eventually develop resistance to such therapy. The B7 family molecules such as CTLA-4, PD-1, and PD-L1 are pivotal players in immune checkpoints that positively or negatively regulate various immune responses. Recently, immunotherapy based on blocking immune checkpoints with anti-CTLA4, anti-PD-1, or anti-PD-L1 antibodies has been proposed as a potential new approach to the treatment of metastatic RCC. Higher expression of PD-L1 and B7-H4 in the tumors is associated with a poor prognosis in RCCs, however, the clinical impact of serum levels of B7 family molecules has not been elucidated in patients with metastatic RCCs receiving VEGF-targeted agents. We assessed the preoperative serum levels of B7 family molecules, including CD80, CD86, PD-1, PD-L1, B7-H3, B7-H4, and CTLA-4, and CD28 in RCC patients, and determined their relations with various clinicopathological characteristics. Elevated preoperative serum levels of PD-L1 and B7-H4 were correlated with less differentiated tumors, higher invasive and metastatic potential, a worse response to anti-VEGF therapy, and shorter overall survival. These findings suggested that investigating preoperative serum levels of PD-L1 and B7-H4 might not only be useful to assess the biological aggressiveness of RCCs, but also to predict the efficacy of anti-VEGF therapy and the eventual prognosis, indicating the future design of clinical trials of therapies targeting immune checkpoint in advanced RCCs., (© 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Background/aim: Breast cancer is one of the most common and lethal types of cancer among women. We focused on the importance of the immune system in the etiology of breast cancer by investigating critical polymorphisms of cytotoxic T-lymphocyte-associated protein 4 (CTLA4) and cluster of differentiation 28 (CD28) gene, and circulating levels of these proteins., Materials and Methods: A total of 79 patients with breast cancer and 76 healthy controls were enrolled. Molecular assessment of CTLA4 (rs231775&rs5742909) and CD28 (rs3116496) variants were determined with polymerase chain reaction restriction fragment length polymorphism techniques. Circulating levels of soluble forms of CTLA4 and CD28 were analyzed by ELISA., Results: Although no significant association was found between study groups, CTLA4 +49AA genotypic frequency, and sCTLA4 and sCD28 levels were higher in patients. Some clinicopathological features were also related with CTLA4 and CD28 variants and blood levels., Conclusion: While CTLA4 +49AA genotype is increased in patients with breast cancer, the CTLA4 -318T allele may have a prognostic value. In addition, sCTLA4 and sCD28 can be used for diagnostic purposes in patients with breast cancer., (Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Objective: To determine whether circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive (DP) T cells are independently associated with damage accrual in systemic lupus erythematosus (SLE) patients., Methods: This cross-sectional study was conducted between September 2013 and April 2014 in consecutive SLE patients from our Rheumatology Department. CD4+CD28null and CD4+CD8+ DP T-cell frequencies were analyzed by flow-cytometry. The association of damage (SLICC/ACR Damage Index, SDI) and CD4+CD28null and CD4+CD8+ DP T cells was examined by univariable and multivariable Poisson regression models, adjusting for possible confounders. All analyses were performed using SPSS 21.0., Results: Patients' (n = 133) mean (SD) age at diagnosis was 35.5 (16.8) years, 124 (93.2%) were female; all were mestizo (mixed Caucasian and Amerindian ancestry). Disease duration was 7.4 (6.8) years. The SLE Disease Activity Index was 5.5 (4.2), and the SDI 0.9 (1.2). The percentages of CD4+CD28null and CD4+CD8+ DP T cells were 17.1 (14.4) and 0.4 (1.4), respectively. The percentage of CD4+CD28null and CD4+CD8+ DP T cells were positively associated with a higher SDI in both univariable (rate ratio (RR) 1.02, 95% confidence interval (CI): 1.01-1.03 and 1.17, 95% CI: 1.07-1.27, respectively; p < 0.001 for both) and multivariable analyses RR 1.02, 95% CI: 1.01-1.03, p = 0.001 for CD4+CD28null T cells and 1.28, 95% CI: 1.13-1.44, p < 0.001 for CD4+CD8+ DP T cells). Only the renal domain remained associated with CD4+CD28null in multivariable analyses (RR 1.023 (1.002-1.045); p = 0.034)., Conclusions: In SLE patients, CD4+CD28null and CD4+CD8+ DP T cells are independently associated with disease damage. Longitudinal studies are warranted to determine the predictive value of these associations., (© The Author(s) 2015.)

Objective: To compare the different expressions of CD27, CD28, IL-17A, IFN-γ and TNF-α in the peripheral blood sampled from patients with colorectal carcinoma and healthy volunteers., Patients and Methods: Vδ2 T cells were isolated from the peripheral blood mononuclear cells (PBMCs) of patients with the colorectal carcinoma (CRC, n = 30) and healthy controls (HC, n = 21). The proportion of CD27, CD28, IL-17A, IFN-γ and TNF-α of Vδ2 T cells was detected by the flow cytometry., Results: We found that the proportion of IL-17A of Vδ2 T cells in PBMCs was higher in the CRC vs. the HC group (p < 0.05). A significant positive correlation was observed between the expression of IFN-γ and TNF-α of Vδ2 T cells. In the CRC patients, the proportions of IL-17A of CD27- Vδ2 T cells and CD28+ Vδ2 T cells were higher than those of CD27+ Vδ2 T cells and CD28- Vδ2 T cells, whereas the expression of IFN-γ and TNF-α of CD27-Vδ2 T cells was lower than that of CD27+ Vδ2 T cells., Conclusions: Vδ2 T cells from PBMCs had higher expression of IL-17A in CRC patients than that in the HC group. The expression of IFN-γ and TNF-α of Vδ2 T cells from PBMCs was positively correlated. The cytokine profiles of peripheral Vδ2 T cells were likely determined by a CD27 and CD28 involving mechanism.

Background: Histone acetyltransferases (HAT) and histone deacetylases (HDAC) are enzymes that upregulate and down-regulate pro-inflammatory gene transcription respectively. HDAC2 is required by corticosteroids to switch off activated inflammatory genes and is reduced in lung macrophages in COPD. We have shown that COPD patients have increased steroid resistant CD28null (senescent) pro-inflammatory T and NKT-like peripheral blood cells (particularly CD8+ subsets) and we hypothesized that these changes would be associated with a loss of HDAC2 from these senescent pro-inflammatory lymphocytes., Methods: Blood was collected from 10 COPD and 10 aged-matched controls. Intracellular pro-inflammatory cytokines, IFNγ and TNFα, and expression of CD28, HDAC2 and HAT, were determined in lymphocyte subsets in the presence of ± 5 mg/ml theophylline (HDAC2 activator), 10 μM prednisolone and 2.5 ng/ml cyclosporine A (immunosuppressant), using flow cytometry., Results: There was a loss of HDAC2 from CD28null CD8+ T and NKT-like cells in COPD. There was a significant negative correlation between HDAC2 expression and the percentage of CD28null CD8+ T and NKT-like cells producing IFNγ or TNFα in all subjects (eg, COPD: R = -.763, p < 0.001 for T-cell IFNγ). There was a synergistic upregulation of HDAC2 and associated decrease in pro-inflammatory cytokine production in CD28nullCD8+ T and NKT-like cells in the presence of 5 mg/L theophylline + 10(-6) M prednisolone or 2.5 ng/mL cyclosporine A (CsA)., Conclusions: Lymphocyte senescence in COPD is associated with loss of HDAC2 in CD28nullCD8+ T and NKT-like cells. Alternative treatment options such as combined theophylline with low-dose CsA, that inhibit these pro-inflammatory cells, may reduce systemic inflammation in COPD.

Background: Colorectal cancer (CRC) is the third most frequent cancer worldwide. Research has revealed the contributions of the immune system and anti-inflammatory pathways in the development of cancer. The balance between cluster of differentiation 28 (CD28) and cytotoxic T-lymphocyte-associated protein 4 (CTLA4) signaling is important for the regulation of immune responses. The oxidant-antioxidant balance by sustaining redox control via several defense mechanisms is also an important factor for the progression of cancer. The aim of the present study was to determine the distribution of CTLA4/CD28 variants and oxidant-antioxidant status in patients with CRC., Materials and Methods: This study enrolled 80 patients with CRC and 115 healthy controls. We used a spectrophotometric assay to detect the levels of lipid peroxidation products malon dialdehyde (MDA) and lipid hydroperoxide (LHP), and measured the concentration of protein damage products, advanced oxidation protein products (AOPP) and protein carbonyl (PCO). Additionally, antioxidant levels were detected by measuring copper, zinc, superoxide dismutase (Zn-Cu SOD) and total thiol (T-SH) levels, and advanced glycation end-products (AGEs). The CTLA4 -318C>T, CTLA4 49A>G and CD28C>T genotypes were determined by using restriction enzymes., Results: AOPP and PCO levels were increased in patients with CRC as well as those of LHP, MDA and AGE, while the levels of antioxidants such as Cu-Zn SOD and T-SH were lower. Lower serum levels of CTLA4 and higher serum levels of CD28 were detected in patients and, an association of the CTLA4 -318C/T polymorphism was found in patients with CRC., Conclusion: Our oxidative stress was increased in patients with CRC, suggesting the contribution of this disturbed oxidative status to serum CTLA4 and CD28 levels, and to the pathogenesis of CRC., (Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Type-1 diabetes (T1D) is a heterogeneous autoimmune disease, and there are pathogenetic differences between young- and adult-onset T1D patients. We hypothesized that the expressions of genes involved in costimulatory immune system pathways in peripheral blood are differently regulated in young- and adult-onset T1D. Study group I consisted of 80 children, adolescents, and young adults (age range 1.4-21.4 y; 31 controls and 49 T1D patients). Study group II consisted of 48 adults (age range 22.0-78.4 y; 30 controls and 18 T1D patients). The mRNA expression levels of CD86, CD28, CD25, CD226, CD40, BTLA, GITR, PDCD1, FoxP3, TGF-β, ICOS, sCTLA4, flCTLA4, and CD80 were measured in peripheral blood. Genetic polymorphisms (HLA haplotypes; rs231806, rs231775, and rs3087243 in CTLA4; rs763361 in CD226; and rs706778 in CD25) and T1D-associated autoantibodies were analyzed. In group I, there was significantly lower expression of CD226 in T1D patients than in the controls. In group II, there were significantly higher expression levels of CD86 and TGF-β in T1D patients than in the controls. In the T1D patients in group I, the upregulated CD80 expression correlated with the expression of both CTLA4 splice variants (sCTLA4 and flCTLA4). In contrast, in group II, upregulated CD86 correlated with TGF-β and CD25. In group I, the inhibitory CD80-CTLA4 pathway was activated, whereas, in group II, the activation CD86-CD28 pathway and TGF-β production were activated. These results emphasize the differences between young-onset and adult-onset T1D in the regulation of costimulatory pathways. These differences should be considered when developing novel treatments for T1D., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

It is known that dysregulation of the immune system is closely related to the development of lung cancer and that CD8+T lymphocytes play a critical role in antitumor immunity. We analyzed the percentage of CD3+CD8+ T cells in peripheral blood, and expressions of the activated molecules, perforin, CD95, CD28, HLA-DR and CD38 in circulating CD3+CD8+ T cells from 68 lung cancer cases with stage I∼II and 61 lung cancer cases with stage III∼IV by flow cytometry. 61 lung cancer cases with stage III∼IV were followed up for more than 6 months and survival time was recorded. The percentages of perforin+ cells, CD95+ cells and CD38+ cells in fresh CD3+CD8+ T lymphocytes of stage III∼IV group were lower than those of stage I∼II group (p=0.021; p=0.043; p=0.036). And an increased percentage of CD3+CD8+perforin+ cells was shown to have a positive effect on the survival time in stage III∼IV lung cancer patients (p=0.043). Advanced lung cancer patients have characteristics of impairment in the cytotoxicity of circulating CD3+CD8+ T lymphocytes and perforin expression in circulating CD3+CD8+ T cells might be used as a prognostic biomarker for the advanced lung cancer., (© 2015 by the Association of Clinical Scientists, Inc.)

Induction of maternal-fetal immune tolerance is essential for the development of normal pregnancy. Impaired expression of costimulatory molecules may lead to intense inflammatory reaction, a mechanism involved in the pathophysiology of gestational diabetes mellitus (GDM). The aim of this study was to investigate whether immunoregulatory molecules are involved in the physiopathology of GDM. This case-control study included 30 healthy pregnant women and 20 GDM patients. Flow cytometry was used to assess peripheral blood T subpopulations (CD4(+) and CD8(+)), the expression of immunoregulatory molecules (CD28, ICOS, CTLA-4, and PD-1) and activation markers (CD69 and HLA-DR). Compared to healthy women, GDM patients had a significantly higher frequency of CD4(+)CD69(+) and CD8(+)CD69(+) T cells; only patients with insulin-treated GDM had increased numbers of CD4(+)HLA-DR(+) T cells. We also observed significantly higher percentages of CD4(+)CD28(+)HLA-DR(+), CD3(+)CD4(+)ICOS(+), CD3(+)CD4(+)PD-1(+), CD8(+)CD28(+)CD69(+), CD8(+)CD28(+)HLA-DR(+), CD8(+)CTLA-4(+)HLA-DR(+), and CD3(+)CD8(+)ICOS(+) T cells and lower frequency of CD3(+)CD4(+)CTLA-4(+), CD3(+)CD8(+)CTLA-4(+), and CD8(+)ICOS(+)HLA-DR(+) T cells in GDM patients compared to healthy pregnant women. This first study assessing costimulatory molecules in GDM patients shows that these patients have exacerbated markers of T cell activation along with CTLA-4 deficiency, findings that indicate that the maternal-fetal tolerance is compromised in these patients.

Background: Glucocorticoid (GC) resistance is a major barrier in COPD treatment. We have shown increased expression of the drug efflux pump, Pgp1 in cytotoxic/pro-inflammatory lymphocytes in COPD. Loss of lymphocyte co-stimulatory molecule CD28 (lymphocyte senescence) was associated with a further increase in their pro-inflammatory/cytotoxic potential and resistance to GC. We hypothesized that lymphocyte senescence and increased Pgp1 are also associated with down-regulation of the GC receptor (GCR)., Methods: Blood was collected from 10 COPD and 10 healthy aged-matched controls. Flow cytometry was applied to assess intracellular pro-inflammatory cytokines, CD28, Pgp1, GCR, steroid binding and relative cytoplasm/nuclear GCR by CD28+ and CD28null T, NKT-like cells. GCR localization was confirmed by fluorescent microscopy., Results: COPD was associated with increased numbers of CD28nullCD8+ T and NKT-like cells. Loss of CD28 was associated with an increased percentage of T and NKT-like cells producing IFNγ or TNFα and associated with a loss of GCR and Dex-Fluor staining but unchanged Pgp1. There was a significant loss of GCR in CD8 + CD28null compared with CD8 + CD28+ T and NKT-like cells from both COPD and controls (eg, mean ± SEM 8 ± 3% GCR + CD8 + CD28null T-cells vs 49 ± 5% GCR + CD8 + CD28+ T-cells in COPD). There was a significant negative correlation between GCR expression and IFNγ and TNFα production by T and NKT-like cells(eg, COPD: T-cell IFNγ R = -.615; ) and with FEV1 in COPD (R = -.777)., Conclusions: COPD is associated with loss of GCR in senescent CD28null and NKT-like cells suggesting alternative treatment options to GC are required to inhibit these pro-inflammatory/cytotoxic cells.

Background: Chronic exposure to exogenous antigens causes accumulation of proinflammatory CD57(+)CD28(-) hyperactivated CD8(+) T cells that may promote atherosclerosis. We hypothesized that persistent alloimmune responses may induce immune activation and contribute to posttransplant atherosclerosis., Methods: This hypothesis was tested in a single-center cohort of 577 kidney transplant patients. Propensity score analysis was performed to address potential confounding variables by indication. Immune exhaustion was studied in subcohort of 103 patients., Results: Five hundred seventy-seven consecutive renal transplant recipients were included. Seventy-seven atherosclerotic events (AE) (12.3%) occurred during a mean follow-up of 7 years. The cumulative incidence of AE increased with the number of human leukocyte antigen (HLA) mismatches (18%, 10%, and 5% in patients with 5-6, 3-4, and 0-2 mismatches, respectively; P=0.012). Human leukocyte antigen mismatch number (hazards ratio, 1.35; 95% confidence interval, 1.10-1.66, for each supplementary mismatch; P=0.005) was an independent risk factor for AE. In the propensity score match analysis, having received a well-matched kidney conferred a reduced risk of AE (hazards ratio, 0.22; 95% confidence interval, 0.05-0.95; P=0.044). We observed a significant correlation between HLA mismatch numbers and circulating CD57(+)CD28(-) CD8(+) T cells (R=0.31; P=0.017). These CD8(+) T cells were more frequent in patients with more HLA mismatches (P<0.0001)., Conclusion: Overall, our results suggest that chronic allogeneic stimulation participates to accelerated atherosclerosis observed after transplantation.

Long-term survival of H&N cancer patients has not improved significantly over the last 30 years. The possibility of using circulating blood cell phenotypes as a prognostic biomarker of H&N cancer patient was investigated in this study. Pre-treatment, circulating T lymphocyte subpopulations as well as the survival time of the patients in question were studied. Upregulated CD4+ perforin+ and CD8+ CD95+ but downregulated CD4+ CD28+ (p < 0.001) were detected in H&N cancer patients. With 3 years of follow-up time, an increase in the frequency of the pre-treatment, circulating CD4+ perforin+ cells and CD8+ perforin+ cells was showed to have reverse effects on the survival time in H&N cancer patients (p < 0.01). Detection of perforin+ frequency in CD4+ and CD8+ lymphocyte by FACS is fast, simple and cost-effective. A potential role of perforin expression in CD4+ and CD8+ cells as a prognostic biomarker for H&N cancer patient in the clinical setting was suggested.

Balanced immunoregulatory networks are essential for maintenance of systemic tolerance. Disturbances in the homeostatic equilibrium between inflammatory mediators, immune regulators and immune effector cells are implicated directly in the pathogenesis of autoimmune diseases, including rheumatoid arthritis (RA). In this study we characterize the peripheral blood CD8(+) CD28(-) regulatory T cells (Treg) contribution to the immunoregulatory network in health and in RA. In health, CD8(+) CD28(-) Treg are suppressive but, unlike CD4(+) Treg , they function predominantly through the action of soluble mediators such as interleukin (IL)-10 and transforming growth factor (TGF)-β. Neutralization of TGF-β consistently reduced CD8(+) CD28(-) Treg suppressor function in vitro. RA, CD8(+) CD28(-) Treg are increased numerically, but have reduced expression of inducible co-stimulator (ICOS) and programmed death 1 (PD-1) compared to healthy or disease controls. They produce more IL-10 but autologous T cells express less IL-10R. This expression was found to be restored following in-vitro addition of a tumour necrosis factor inhibitor (TNFi). Deficiencies in both the CD8(+) CD28(-) Treg population and reduced sensitivity of the T responder cells impact upon their regulatory function in RA. TNFi therapy partially restores CD8(+) CD28(-) Treg ability in vivo and in vitro, despite the defects in expression of functionally relevant molecules by RA CD8(+) CD28(-) Treg compared to healthy controls. This study places CD8(+) CD28(-) Treg cells in the scheme of immune regulation alongside CD4(+) Treg cells, and highlights the importance of understanding impaired responsiveness to regulation that is common to these suppressor subsets and their restored function in response to TNFi therapy., (© 2013 British Society for Immunology.)

To present the relationship between high CD8+ T-cell activation and poor outcome in HIV-1 pathogenesis. We hypothesized that the decrease of interleukin-21 (IL-21) levels would lead to alterations in survival of elevated immune activation with disease progress. Fifty-eight HIV-1-seropositive subjects and 21 uninfected healthy control volunteers were recruited in this study. The serum IL-21 concentrations and the levels of expression of CD38, HLA-DR, and IL-21 receptor in CD8 T cells were detected by flow cytometry. The percentages of both CD38 and HLA-DR cells in CD8 T cells were significantly inversely related to the serum IL-21 levels. IL-21 plays an important role in the mechanism of elevated CD8+ T cell immune activation leading to poor outcome in HIV-1 pathogenesis, which will be helpful for the development of current and future anti-HIV strategies.

CD4(+)CXCR5(+)Foxp3(+) follicular regulatory T cells (T(FR) cells) inhibit humoral immunity mediated by CD4(+)CXCR5(+)Foxp3(-) follicular helper T cells (T(FH) cells). Although the inhibitory receptor PD-1 is expressed by both cell types, its role in the differentiation of T(FR) cells is unknown. Here we found that mice deficient in PD-1 and its ligand PD-L1 had a greater abundance of T(FR) cells in the lymph nodes and that those T(FR) cells had enhanced suppressive ability. We also found substantial populations of T(FR) cells in mouse blood and demonstrated that T(FR) cells in the blood homed to lymph nodes and potently inhibited T(FH) cells in vivo. T(FR) cells in the blood required signaling via the costimulatory receptors CD28 and ICOS but were inhibited by PD-1 and PD-L1. Our findings demonstrate mechanisms by which the PD-1 pathway regulates antibody production and help reconcile inconsistencies surrounding the role of this pathway in humoral immunity.

Background: Autoantibodies against CD28 have been found in patients with autoimmune and atopic diseases. These antibodies may act as superagonists and activate T cells but may also be antagonistic or induce immunosuppressive effects by activating regulatory T cells. Autoimmunity in melanoma patients has been discussed controversially., Objective: We investigated 230 melanoma patients for the occurrence of CD28 antibodies and the effect of the latter on overall and progress-free survival., Methods: We constructed an ELISA assay to measure CD28 serum antibodies. 230 patients with melanoma and a control-group of 625 patients consistent of 212 patients with virus hepatitis b or c, 149 patients with allergies, 78 patients with psoriasis, 46 patients with plasmocytoma and 140 healthy blood donors were investigated for the occurrence of CD28 antibodies., Results: CD28 abs occur at a higher percentage in patients with melanoma and in patients with viral hepatitis than in other groups investigated (p<0.001). Occurrence of CD28 abs is significantly higher in patients receiving interferons independent from the underlying disease (p<0.001). In vitro CD28 serum antibodies have an inhibitory effect on the CD28 receptor as they lead to reduced stimulation of Jurkat cells. Presence of CD28 was correlated with a higher risk of dying from melanoma (p = 0.043), but not with a significantly shortened overall survival or progression-free survival., Conclusion: Interferon therapy appears to induce the production of CD28 abs. In light of reports that these CD28 abs induce immunosuppressive Tregs and - as our data show - that they are inhibitors of CD28 receptor mediated stimulation, the continuation of therapies with interferons in melanoma patients developing CD28 antibodies should be critically reconsidered, since our data indicate a worse outcome of patients with CD28 abs.

Introduction: Studies on biomarkers of tolerance in organ transplantation have been widely performed during the last decade., Aim: To assess biomarkers in relation to evolution of the immune response among lung transplant recipients., Methods: This multicenter study included 27 lung transplant recipients followed before as well as at 7, 14, 30, 60, 90, and 180 days posttransplantation. Biomarkers of the immune response based on flow cytometry technology were validated in each center. They included intracellular cytokine expression, regulatory T-cell level, as well as lymphocyte surface antigen and CD28 expressions., Results: The 13 patients who developed acute rejection episodes showed increased numbers of regulatory T cells at 12 months posttransplant. Sixteen patients experiencing infections displayed decreased expression of CD69 on CD8 T cells within the first year of follow-up., Conclusion: High Treg levels in the peripheral blood of lung transplant recipients were associated with an increased risk of rejection but not infection. Inversely, we observed low levels of activated CD8 T cells in infected patients., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objective: There is emerging evidence for CD8(+) T cell alterations in blood from patients with coronary artery disease (CAD). We examined whether the distribution and phenotype of CD8(+)CD56(+) T cells differed according to the clinical manifestation of CAD., Methods: Patients with acute coronary syndrome (ACS, n = 30), stable angina (SA, n = 34) and controls (n = 36) were included. Blood was collected before and up to 12 months after referral for coronary investigation. CD8(+)CD56(+) T cells were assessed by flow cytometry for expression of surface markers, apoptosis, and intracellular expression of cytokines., Results: The proportions of CD8(+)CD56(+) T cells were significantly higher in both ACS and SA patients compared with controls, and remained so after 3 and 12 months. This was independent of age, sex, systemic inflammation and cytomegalovirus seropositivity. CD8(+)CD56(+) T cells differed from CD8(+)CD56(-) T cells in terms of lower CD28 expression and fewer apoptotic cells. Both CD8(+) T cell subsets were positive for interferon (IFN)-γ and tumor necrosis factor, although IFN-γ was significantly more confined to the CD8(+)CD56(+) T cells., Conclusion: The persistent accumulation of CD8(+)CD56(+) T cells in ACS and SA patients share several features with immunological aging. It also contributes to a larger IFN-γ(+) pool in blood, and may thereby hypothetically drive the atherosclerotic process in a less favorable direction., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

CD28 expression and serum levels are significantly increased in patients with SLE than in healthy controls (HC). Until now, there are no studies of proximal promoter polymorphisms of CD28 gene in SLE. Therefore, our objective was to investigate the polymorphisms present in the proximal promoter of CD28 in a group of SLE and HC and to associate the polymorphisms present with the CD28 serum levels of 40 patients and 40 controls. One hundred and seven patients as well as 108 controls matched by age range and genders were included. The 11 ACR criteria were analyzed on the clinical files, and the proximal promoter region of CD28 gene was analyzed by direct sequencing of a 489-basepair fragment. C28 serum levels (sCD28) were measured by ELISA technique in 40 patients and 40 controls. Only two of the eight reported polymorphisms were found, and they correspond to rs35593994 (-372 A/G) and rs56156157 (-145 -/C). The first had a prevalence of 41 and 36% in patients and controls respectively and the second of 1.4% in both groups. None of these polymorphisms were associated with SLE, and the polymorphism -372 A/G was not associated with the clinical features of disease. Likewise, the association with the sCD28 and the genotypes of -372 A/G polymorphism was not significant. The polymorphisms of the proximal promoter of CD28 are not associated with SLE, and the polymorphism -372 A/G is not associated with the diagnostic criteria of SLE or the sCD28.

Background/aims: We investigated serum viral kinetics and peripheral blood lymphocyte dynamics in chronic hepatitis B patients during the first year of tenofovir therapy., Methodology: Fifteen patients, naive to any kind of previous antiviral therapy, were included in this study. The patients received tenofovir daily 245mg for 48 weeks. Fifteen age and gender compatible healthy subjects were enrolled as the control group. Clinical, biochemical, immunological and virological parameters were assessed at baseline, then at the first, third, sixth and twelfth months., Results: CD4+CD25+FOXP3+ nTregs percentages were significantly higher in the study group than that of healthy controls, CD4+CD28+ and CD4+CD38+ T cell percentages were significantly lower in the study group than those of control group (p<0.001). Twelve cases had undetectable HBV DNA levels after the one year therapy. We determined that there was an increase of the CD28+co-stimulator molecule on both the CD4+ and CD8+ T cells while a decrease of the CD8+CD38+ T cells, CD4+CD38+ T cells and CD4+CD25+FOXP3+ nTregs, in patients with tenofovir treatment, but only CD4+CD25+FOXP3+ nTregs were statistically significant., Conclusions: We found that both viral load and CD4+CD25+FOXP3+ nTreg percentages decreased significantly in patients with chronic hepatitis B virus infection during 1 year course of tenofovir treatment.

Background: Soluble forms of CD28 (sCD28) and CTLA-4 (sCTLA-4) were associated with many autoimmune diseases like Sjögren's syndrome, systemic lupus erythematosus, asthma, and autoimmune myasthenia gravis. However, sCD28 and sCTLA-4 in neuromyelitis optica (NMO) and multiple sclerosis (MS) patients were less studied., Objective: To measure the plasma sCD28, sCTLA-4 in NMO and MS patients, and investigate whether sCD28 and sCTLA-4 possible use as sensitive biomarkers for diseases activity., Methods: Plasma concentrations of sCD28, sCTLA-4 were measured by an enzyme-linked immunosorbent assay (ELISA) in NMO (n=22), MS (n=21) patients and controls (n=18)., Results: The concentration of sCD28 levels were higher in the inflammatory demyelinating diseases cohort compared with the controls (NMO, p=0.034; MS, p=0.026) and the levels of sCD28 were slightly higher in NMO compared with MS. The sCTLA-4 levels were lower in the MS subgroup compared with the controls (p=0.032). Both sCD28 and sCTLA-4 did not show any correlation with EDSS score in NMO and MS patients., Conclusions: Our study revealed for the first time that the levels of increased plasma sCD28 and decreased plasma sCTLA-4 in NMO and MS patients, but had little correlation with clinical presentations., (Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.)

Background: The extrathyroid, orbital manifestation of Graves' disease (GD)--Graves' orbitopathy (GO)--presents a difficult clinical problem. The immunological status of GO patients is still under investigation. The aim of this study was to assess the serum concentration of interleukin 6 (IL-6), soluble interleukin 6 receptor (sIL-6R), and CD8+CD28- lymphocytes in GO patients and to evaluate if these parameters were associated with disease activity., Patients: Thirty-nine patients (29 women and 10 men, aged 24-71, mean 50.18) with newly diagnosed GD were enrolled in the study. Active GO was diagnosed in 20 patients. The control group included 12 healthy individuals., Methods: Serum concentrations of IL-6 and sIL-6R were estimated by ELISA. Percentages of CD8+CD28- lymphocytes in peripheral blood were assessed by flow cytometry., Results: Mean serum IL-6 and sIL-6R concentrations were significantly higher in all GD patients and in GO and non-GO patients than in normal controls. In all GD patients and the non-GO group, serum IL-6 and sIL-6R concentrations were significantly reduced after efficient treatment. In GO patients, only serum sIL-6R concentration was significantly lower after efficient treatment. In all GD patients, the mean percentage of CD8+CD28- lymphocytes was significantly lower after efficient treatment. In GO patients, the mean percentage of CD8+CD28- lymphocytes was significantly higher than in the non-GO group or in normals. Moreover, in the GO group, the mean percentage of CD8+CD28- lymphocytes was significantly lower after treatment., Conclusion: Our results have shown that CD8+CD28- lymphocyte percentage in peripheral blood and serum concentration of sIL-6R are increased in GO patients and correlate with disease activity.

Introduction: Rheumatoid arthritis (RA) is a chronic autoimmune disease and it is known that lymphocytes play a major role in its pathogenesis. However, there have been no comprehensive studies on the changes in peripheral blood lymphocyte (PBL) subpopulations expressing different clusters of differentiation (CD) in patients with long-lasting RA., Objectives: The aim of our study was to measure the main subpopulations of PBL, expression of costimulatory marker CD28, and activation status of CD4+ T cells depending on clinical disease activity in long-lasting RA., Patients and Methods: The study comprised 60 patients with RA and 19 healthy volunteers. Disease activity, the proportion and number of the main PBL subpopulations (T, B, natural killer [NK], and NK T cells [NKT]), the expression of costimulatory marker CD28, and the activation status of CD4+ T cells were evaluated on the same day. A multicolor flow cytometry with marked monoclonal antibodies was used for the assessment of lymphocyte subpopulations., Results: The percentage of CD3+CD4+, NKT, CD4+CD28-, CD8+CD28-, CD4+CD69+, CD4+CD25+, and CD4+HLA-DR+ was significantly higher in RA compared with the control group. A higher proportion of CD4+CD28- was associated with more active disease, while an inverse correlation was observed for B cells. The proportion of CD4+CD28- was not associated with disease activity. The number of CD4+CD69+ cells in RA patients increased with increasing DAS28, while the number of CD4+HLA-DR+ T cells showed no such association., Conclusions: Our results have shown for the first time an association between the phenotype patterns of PBL T, B, and NKT and RA activity in patients with long-lasting disease, which reinforces the hypothesis that PBL play an important role in modifying or maintaining the disease activity.

Chronic graft-versus-host disease (cGVHD) is a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Currently, no reliable biomarkers are available to predict the onset or progression of cGVHD. Therefore, in this study, we collected peripheral blood mononuclear cells from four patients with cGVHD and four ones with non-GVHD after hematopoietic stem cell transplantation and employed Affymetrix GeneChip Human U133 Plus 2.0 microarrays to screen the genes differentially expressed in cGVHD versus non-GVHD groups, with the aim to identify potential clinical biomarkers to predict cGVHD risk or progression. Microarray analysis demonstrated that the expression of 3180 genes changed significantly in cGVHD versus non-GVHD, with 879 genes upregulated and 2301 genes downregulated. Among them we chose CD28 and PI3K as candidates for further verification. Flow cytometry and quantitative real-time polymerase chain reaction analysis confirmed the significant upregulation of CD28 and PI3K in samples from patients with cGVHD compared with patients with non-GVHD, respectively. In conclusion, our study suggested that the upregulation of CD28 and PI3K contributed to the onset and progression of cGVHD and provided evidence that CD28 and PI3K may serve as promising biomarkers for cGVHD.

CD28 is one of the main activator receptors involved in systemic lupus erythematosus (SLE) pathogenesis, and its expression and serum levels are significantly higher in patients with SLE and other autoimmune diseases than in healthy controls (HC). However, it is unknown whether this increase is associated with specific organ damage. Therefore, our objective was to measure the CD28 levels in serum from SLE and HC groups to confirm the CD28 serum levels increase, as reported previously, and to determine whether this increase was associated with specific organ activity and the SLE Disease Activity Index (SLEDAI). Forty SLE patients and 40 matched HC were included, and the age, disease duration, SLEDAI and Mexican SLEDAI were recorded for the SLE group. CD28 serum levels were measured by ELISA. There was a statistically significant increase in the CD28 serum levels of SLE patients compared to controls (p = 0.039); however, we did not find any significant correlation with disease activity indices or organ involvement, although we found a significant but low correlation with C3. Our results and a review of the literature suggest that the increase in CD28 serum levels may be the result of CD28 gene overexpression, which could be related to the decrease in CD28+ T cells, T-cell hyporesponsiveness and immune impairment that occurs in SLE.

Co-stimulation signals are critical for anti-viral immunity. Here we investigated whether there is altered expression and the clinical significance of soluble co-stimulatory molecules in patients with chronic HBV infection. Serum concentrations and ex vivo production of soluble CTLA-4, CD28, CD80 and CD86 were analyzed by enzyme-linked immunosorbent assay. Serum sCTLA-4 and sCD28 concentrations in all chronic HBV patients were significantly higher than concentrations in healthy control subjects. Serum sCTLA-4 and sCD28 correlated significantly with alanine aminotransferase in all chronic HBV patients. Upon mitogen stimulation of peripheral blood mononuclear cells, the percentage increases in ex vivo production of sCD28 and sCD80 and the percentage decrease in sCTLA-4 release were all significantly lower in chronic HBV patients than those in healthy subjects. The aberrant production of soluble co-stimulatory molecules should reflect the dysregulation of T cell activation and is related to the pathogenesis and severity of chronic HBV infection., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Viral infections and cellular acute rejection (AR) condition immunosuppressive therapy and compromise the evolution of allografts. Immune monitoring can be useful for ascertaining rejection and for differentiating allo-reaction from activation induced by infections. This work analyzes the usefulness of monitoring the expression of CD28 and KIR2D receptors in peripheral blood T lymphocytes by flow cytometry, to ascertain the immune response in heart and liver transplant recipients. In both types of transplant, the up-regulation of CD28 in CD4(+) lymphocytes in the periods of greatest AR frequency indicates an effective allo-response, whereas the post-transplantation emergence of circulating CD8(+)CD28(-) and CD8(+)CD28(-)KIR2D(+) T cells correlates with better early clinical results. Cytomegalovirus (CMV) infection, but not hepatitis C virus (HCV) or other infections, abrogated both CD28 up-regulation and CD8(+)CD28(-)KIR2D(+) T-cell expansion. Our results show that monitoring the expression of CD28 and KIR2D receptors on T lymphocytes might be considered as sensors of the immune status of heart and liver recipients., (Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Introduction: In recent studies, the FOXP3 molecule has been suggested to be a marker of a suppressor subset of human CD8+ CD28- T cells based on correlations between the level of its mRNA and allograft function. Because this transcriptional factor produces a protein, we suggest that these correlations should focus on the FOXP3 protein. The aim of our study was to evaluate whether FOXP3 protein was present in cells of the CD8+ CD28- population in the peripheral blood of renal allograft recipients and whether the level of CD8+ CD28- FOXP3+ cells correlated with allograft function., Methods: The study was performed on 30 renal allograft recipients with uneventful stable courses (n=18) or biopsy-proven chronic rejection (n=12). The immunosuppression was based on cyclosporine (n=12) or rapamycin (n=9). Peripheral blood mononuclear cells isolated from recipient blood samples were labeled with anti-CD8 and anti-CD28 MAbs conjugated with fluorochromes. After incubation, washing, and labeling using a PE anti-human FOXP3 Kit, we determined the percentage of cells by flow cytometry., Results: FOXP3 protein expression was not observed either in the CD8+ CD28- population, or the whole populations of CD8+ or CD28- cells among patient groups., Conclusions: The expression of FOXP3 protein in CD8+ CD28- cells seems to be of a questionable value as a diagnostic tool for allograft function, it is probably not a marker for the CD8+ CD28- T cell subset., (Copyright © 2011 Elsevier Inc. All rights reserved.)