ABSTRACT
OBJECTIVE@#To investigate the effect of sputum ubiquitin ligase (Cbl-b) gene known-down on the cytotoxicity of H9 T lymphocytes against human laryngeal squamous cancer Hep-2 cells and explore the underlying mechanism.@*METHODS@#CD4 T lymphocytes isolated from 12 patients with laryngeal squamous carcinoma and 12 healthy individuals were examined for Cbl-b mRNA expressions using RT-PCR. H9 T lymphocytes cultured in 96-well plates were transfected with Cbl-b siRNA via liposomes followed by treatment with an anti-IL-2 monoclonal antibody, with H9 T lymphocytes transfected with a scrambled sequence as the negative control. The expressions of Cbl-b mRNA and protein in the cells were detected using real-time fluorescent quantitative PCR and Western blotting, respectively. The killing effect of the treated T lymphocytes against Hep-2 cells was assessed using the cell counting kit (CCK-8). The positive expression rates of CD69 and CD25 on the surface of H9 T lymphocytes were determined using flow cytometry, and the levels of interleukin-2 (IL-2) and interferon-gamma (INF-γ) in the culture supernatants of H9 T lymphocytes were detected with ELISA.@*RESULTS@#The CD4 T lymphocytes from patients with laryngeal squamous carcinoma showed significantly increased Cbl-b mRNA level compared with those from healthy individuals ( < 0.05). Transfection of H9 T lymphocytes with Cbl-b siRNA significantly reduced the expression levels of Cbl-b mRNA and protein ( < 0.05), which were not significantly affected by subsequent treatment of the cells with the anti-IL-2 antibody (>0.05). At different target-effector ratios, the Cbl-b siRNA-transfected cells showed significantly higher Hep-2 cell killing rates and higher positivity rates of CD69 and CD25 expressions than the blank and negative control cells and the cells with both Cbl-b siRNA transfection and anti-IL-2 treatment ( < 0.05). Cbl-b silencing in H9 T lymphocytes resulted in significantly increased levels of IL-2 and INF-γ in the supernatant as compared with those in the blank and negative control groups ( < 0.05).@*CONCLUSIONS@#Cbl-b gene silencing effectively enhances the killing effect of H9 T lymphocytes against Hep-2 cells probably as the result of enhanced IL-2 secretion and T lymphocyte activation.
Subject(s)
Humans , Carcinoma, Squamous Cell , Genetics , Therapeutics , Gene Silencing , Laryngeal Neoplasms , Genetics , Therapeutics , Lymphocyte Activation , RNA, Small Interfering , T-LymphocytesABSTRACT
Tuberculosis(TB) is mainly caused by Mycobacterium tuberculosis (Mtb),which in the body long-term existence is closely related to the immune escape mechanism.Mtb's immune escape mechanisms have been found to include prevention of phagosomal maturation and acidification of lysosomes,suppression of oxidative stress,inhibition of apoptosis and autophagy.Mtb immune escape mechanism to avoid the host is complex,not yet fully understood.This article focuses on Mtb im mune escape mechanism as a review,is an in-depth study to provide a reference.
ABSTRACT
The killing effects of lymphocytes on Hela cells expressing intedeukin-12 (IL-12) in vitro were explored. By using gene transfection technique, full length IL-12 gene was transfected into Hela cells. The expression of IL-12 in Hela cells was detected quantitatively by ELISA; Changes in killing effects of lymphocytes on Hela cells expressing IL-12 were observed by MTT. It was found that Hela cells could express IL-12 between 24h and 72h after transfection. Killing activity of lymphocytes on Hela cells expressing IL-12 was significantly enhanced. It was concluded by cell transfection technique, Hela cells could express IL-12 and were more easily killed by lymphocytes.