B and T lymphocyte attenuator as a C-reactive protein and IgA associated auxiliary diagnostic marker for pulmonary tuberculosis: a case-control study

Abstract

Background: Screening and identification of hematologic molecular indicators of pulmonary tuberculosis (PTB) is crucial for its diagnose and therapy. Therefore, our work aims to detect the diagnostic value of blood marker B and T lymphocyte attenuator (BTLA) in PTB, and provide a certain theoretical basis for the auxiliary diagnosis of PTB. Methods: Based on the inclusion criteria, 56 Patients with clinically confirmed pulmonary TB by clinical between January 2020 and December 2021 at our hospital were selected as the research objects of this study. Fifty-two matched healthy population at our hospital was used as the control group. Clinical characteristics were got from clinical laboratory. Real-time polymerase chain reaction (RT-PCR) was used to analyze changes in BTLA along with its ligand in peripheral blood. Changes in BTLA on the surface of different cells were analyzed by flow cytometry. The correlation test was used to determine the associations between BTLA and clinical indicators. Receiver operating characteristic (ROC) curve analysis was used to evaluate the auxiliary diagnostic value in PTB of BTLA expression from different sources.Results: Compared with the control, changes in peripheral blood BTLA in the PTB group were significantly increased (P=0.0187) rather than its ligand. Changes in BTLA on the surface of CD68 and antigen-presenting cell (APC) CD11c were significantly increased in the PTB group (P=0.0004, P<0.0001), while changes in BTLA on the surface of CD4 + T and CD8 + T cells were not significantly different (P=0.0792, P=0.8706). The expression of BTLA + CD11c + was negatively correlated with the expression of immunoglobulin A (IgA) (r=−0.2934, P=0.0282) and positively related to C-reactive protein (r=0.3277, P=0.0137). ROC curve analysis suggested that the area under the curve (AUC), sensitivity and specificity of BTLA RT-PCR detection were 0.6315, 53.57%, 57.69% while for BTLA + CD11c + detection were 0.8039, 88.46% and 73.21% and for BTLA + CD68 + detection were 0.6973, 60.71% and 61.54%.Conclusions: BTLA is highly expressed in peripheral blood and specific cell types of patients with PTB and is correlated with specific clinical indicators, which may be an important molecular marker for the auxiliary diagnosis of PTB.

The Methylation in B7-H4 and BTLA Genes are Associated with the Risk of Pulmonary Tuberculosis

“… 18 Another study demonstrated that the expression of CD11c + BTLA was positively related to CRP, which might be correlated with inflammatory changes in PTB patients. 29 The present study mainly focused on studying the association of four SNPs (rs1982809, rs2971205, rs75368388, rs9288953) in BTLA gene with PTB risk, while no significant association was found between these SNPs and the risk of PTB. Contrary to our study, previous studies displayed significant correlation between BTLA gene polymorphisms and cancer, autoimmune diseases.…”