Prognostic value of angiogenic T cells in hepatitis B-induced liver cirrhosis

This study was performed to investigate the frequency of angiogenic T cells (CD4+ Tang cells) among CD4+ T cells in patients with hepatitis B-induced liver cirrhosis (HBV-LC) and to evaluate the predictive role of these cells in the clinical outcome. In total, 185 patients with HBV-LC were recruited to measure the frequency of CD4+ Tang cells and chemokine levels using flow cytometry. RESULTS: There was 11.4% of death after 3-momth follow-up. The AUC for the ability of the frequency of CD4+ Tang cell to predict death was 0.724 (higher than those for the MELD score, FIB-4 score, and Child-Pugh classification). Cox regression analysis revealed an association between the frequency of CD4+ Tang cells and a 3-month survival chance. CONCLUSIONS: The lower frequency of CD4+ T ang cells was correlated with the severity of HBV-LC and may serve as a prognostic predictor.

Methotrexate improves endothelial function in early rheumatoid arthritis patients after 3 months of treatment

Background

Endothelial dysfunction contributes to increased cardiovascular (CV) disease in rheumatoid arthritis (RA). Angiogenic T cells (Tang) are a key regulator of vascular function via their interaction with endothelial progenitor cells (EPCs). Methotrexate (MTX) has been associated to reduced CV disease risk, but its effects on endothelial homeostasis have been poorly explored. We investigated MTX effects on endothelial homeostasis in early, treatment-naïve RA patients.

Methods

Fifteen untreated, early RA patients and matched healthy controls (HC) were enrolled. RA patients with long-standing disease in remission or low disease activity treated with MTX for at least 6 months were selected as controls. Circulating CD28⁺ and CD28^null Tang cell, endothelial microparticle (EMP), EPC and soluble vascular cell adhesion molecule (sVCAM)-1 levels were measured.

Results

Tang percentage was higher in early RA than in HCs and significantly increased after 3-month MTX treatment. Tang cells in RA were characterized by higher percentage of CD28^null and lower CD28-positive cells than HCs. MTX restored a Tang cell phenotype similar to HCs. Altered sVCAM-1, EMP and EPC were restored to levels similar to HCs after a 3-month MTX. Biomarker levels after 3 months of MTX were not different to those of patients with long-standing treatment.

Conclusions

MTX has a positive effect on Tang, sVCAM-1, EPCs and EMPs in RA. Restoration of imbalance between CD28 + and CD28^null Tang by MTX may be one of the mechanisms underlying its favourable effects on endothelial dysfunction. These effects seem to be long-lasting and independent from systemic inflammation reduction, suggesting a direct effect of MTX on the endothelium.

The risk of circulating angiogenic T cells and subsets in patients with systemic sclerosis

To ascertain the number and percentage of angiogenic T (Tang) cell subsets by flow cytometry in systemic sclerosis (SSc), and their relation with specific clinical features. Thirty SSc patients and 15 healthy controls (HCs) were included. Luminex was performed to analyze the levels of interleukin (IL)-17A, vascular endothelial growth factor (VEGF), tumor necrosis factor-α, and vascular cell adhesion molecule (VCAM). The ratio of circulating CD3 + CD31 + CXCR4 + T (CD3 + Tang) cells and CD8+ CD31 + CXCR4 + T (CD8+ Tang) cells in SSc patients was enlarger than in HCs, while CD4 + CD31 + CXCR4 + T cells (CD4 + Tang) exhibited no difference between SSc patients and HCs. The number and percentage of Tang cells were higher in SSc patients with pulmonary artery hypertension (PAH) than in non-PAH SSc patients and HCs. The ratios of Tang cell subsets in nucleolar pattern-positive SSc patients were markedly raised as compared with their negative ones and HCs. Additionally, the percentage of circulating CD3 + Tang cells was positively associated with VEGF serum levels in SSc patients. Meanwhile, the rate of CD8+ tang cells might have been emphatically corresponded to VEGF and VCAM serum levels in SSc patients. These results imply that the increase in Tang cells in peripheral blood are associated with immunoregulatory disturbances in SSc patients.

Circulating angiogenic cell response to sprint interval and continuous exercise

INTRODUCTION

Although commonly understood as immune cells, certain T lymphocyte and monocyte subsets have angiogenic potential, contributing to blood vessel growth and repair. These cells are highly exercise responsive and may contribute to the cardiovascular benefits seen with exercise.

PURPOSE

To compare the effects of a single bout of continuous (CONTEX) and sprint interval exercise (SPRINT) on circulating angiogenic cells (CAC) in healthy recreationally active adults.

METHODS

Twelve participants (aged 29 ± 2 years, BMI 25.5 ± 0.9 kg m^- 2, [Formula: see text]peak 44.3 ± 1.8 ml kg^- 1 min^- 1; mean ± SEM) participated in the study. Participants completed a 45-min bout of CONTEX at 70% peak oxygen uptake and 6 × 20 s sprints on a cycle ergometer, in a counterbalanced design. Blood was sampled pre-, post-, 2 h and 24 h post-exercise for quantification of CAC subsets by whole blood flow cytometric analysis. Angiogenic T lymphocytes (T_ANG) and angiogenic Tie2-expressing monocytes (TEM) were identified by the expression of CD31 and Tie2, respectively.

RESULTS

Circulating (cells µL^- 1) CD3⁺CD31⁺ T_ANG increased immediately post-exercise in both trials (p < 0.05), with a significantly greater increase (p < 0.05) following SPRINT (+ 57%) compared to CONTEX (+ 14%). Exercise increased (p < 0.05) the expression of the chemokine receptor CXCR4 on T_ANG at 24 h. Tie2-expressing classical (CD14⁺⁺CD16^-), intermediate (CD14⁺⁺CD16⁺) and non-classical (CD14⁺CD16⁺⁺) monocytes and circulating CD34⁺CD45^dim progenitor cells were higher post-exercise in SPRINT, but unchanged in CONTEX. All post-exercise increases in SPRINT were back to pre-exercise levels at 2 h and 24 h.

CONCLUSION

Acute exercise transiently increases circulating T_ANG, TEM and progenitor cells with greater increases evident following very high intensity sprint exercise than following prolonged continuous paced endurance exercise.

Older men display elevated levels of senescence-associated exercise-responsive CD28null angiogenic T cells compared with younger men

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; TANG ) 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 (CD28null ) TANG cells and whether these cells were more exercise responsive than CD28+ TANG 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˙O2 peak, with circulating TANG 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 TANG cells (mean ± SEM: 410 ± 81 vs. 784 ± 118 cells·μL, P = 0.017), despite a greater proportion of these cells being CD28null (26.26 ± 5.08 vs. 13.36 ± 2.62%, P = 0.044). Exercise significantly increased the circulating number of TANG cells in both young and older men. However, in older men alone, exercise preferentially mobilized CD28null CD8+ TANG cells compared with CD28+ TANG 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 TANG cells, older adults display greater levels of senescent TANG cells in comparison with younger individuals, and these cells are more exercise responsive than CD28+ TANG cells. Lower number of circulating TANG and greater levels of senescent-associated CD28null TANG may contribute to greater CVD risk with advancing age.