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Despite past extensive studies on B and T lymphocyte attenuator (BTLA)-mediated negative regulation of T cell activation, the role of BTLA in antigen presenting cells (APCs) in patients with active pulmonary tuberculosis (ATB) remains poorly understood. Here, we demonstrate that BTLA expression on CD11c APCs increased in patients with ATB. Particularly, BTLA expression in CD11c APCs was likely associated with the attenuated stimulatory capacity on T cells (especially CD8+ T cell) proliferation. BTLA-expressing CD11c APCs showed lower antigen uptake capacity, lower CD86 expression, higher HLA-DR expression, and enhanced IL-6 secretion, compared to counterpart BTLA negative CD11c APCs in healthy controls (HC). Interestingly, BTLA-expressing CD11c APCs from ATB patients displayed lower expression of HLA-DR and less IL-6 secretion, but higher expression of CD86 than those from HC volunteers. Mixed lymphocyte reaction suggests that BTLA expression is likely associated with positive rather than conventional negative regulation of CD11c APCs stimulatory capacity. This role is impaired in ATB patients manifested by low expression of HLA-DR and low production of IL-6. This previous unappreciated role for BTLA may have implications in the prevention and treatment of patients with ATB., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background and Aims: Macrophages and Toll-like receptor 4 (TLR4) are involved in the inflammatory process of adipogenesis. This study aimed to characterize macrophage infiltrates and the associated TLR4 expression in different locations of white adipose tissues (WAT) of male Chinese and determine their correlations to adipocyte hypertrophy and hyperplasia., Methods and Results: A total of 30 men, who were lean, overweight or with type 2 diabetes (T2D), were recruited. Their abdominal omental WAT (oWAT) and subcutaneous WAT (scWAT) were obtained. The contents of macrophages in oWAT and scWAT were quantified using anti-CD68 staining. The levels of TLR4 expression were analyzed by western blot assays and the adipocyte size was quantified, followed by linear regression analysis. Significantly higher numbers of macrophages (24.4+/-3.2 vs 6.1+/-2.9, p<0.001), associated with higher levels of TLR4 expression (0.59+/-0.19 vs 0.20+/-0.03, p<0.001), were observed in oWAT, as compared with that in scWAT. Furthermore, the levels of macrophage infiltrates and TLR4 expression in oWAT of subjects who were overweight or/and have T2D were significantly higher than that in the lean group. The average adipocyte diameters and cross-sectional areas in oWAT of subjects who were overweight were significantly greater than those in the lean group (p=0.003 and p=0.04, respectively). Importantly, the numbers of macrophage infiltrates were positively correlated to the levels of TLR4 expression, the sizes of adipocytes, the levels of body mass index and C-reactive protein, respectively., Conclusion: Our data suggest that macrophage-related TLR4 expression and inflammation contribute to the development of adipocyte hypertrophy in male Chinese.