Tumor Transplantation for Assessing the Dynamics of Tumor-Infiltrating CD8<sup>+</sup> T Cells in Mice

T cell-mediated immunity plays a crucial role in immune responses against tumors, with cytotoxic T lymphocytes (CTLs) playing the leading role in ...

Third Military Medical University

The objective of this study was to evaluate the efficacy of combined therapy using Sorafenib and radiofrequency ablation (RFA) with curative intent for all detectable lesions in patients with Barcelona Clinic Liver Cancer (BCLC) Stage 0-B1 hepatocellular carcinoma (HCC).

Combination therapy with sorafenib and radiofrequency ablation for BCLC Stage 0-B1 hepatocellular carcinoma: a multicenter retrospective cohort study.

Hepatectomy is currently routinely performed in most hospitals in China. China owns the largest population of liver diseases and the biggest number of liver resection cases. A nationwide multicenter retrospective investigation involving 112 hospitals was performed, and focused on liver resection for patients with hepatocellular carcinoma (HCC). 42,573 cases of hepatectomy were enrolled, and 18,275 valid cases of liver resection for HCC patients were selected for statistical analysis. The epidemiology of HCC, distribution of hepatectomy, postoperative complications and prognosis were finally analyzed. In the 18,275 HCC patients, 81% had hepatitis B virus infection and 10% had hepatitis C virus infection. 38% of the HCC patients had normal Alphafetoprotein (AFP) level, and other 35% had an AFP level lower than 400 ng mL. In the study period, 97% of the hepatectomy for HCC were treated with open surgery, and 23.81% had vascular exclusion techniques. The operation time was (191.7±105.6) min, the blood loss was (546.0±562.8) mL, and blood transfusion was (543.0±1,035.2) mL. The median survival for HCC patients was 631 days, with 1-, 3-, and 5-year overall survival of 73.2%, 28.8% and 19.6%, respectively. Liver cirrhosis, multiple nodules, tumor thrombosis and high AFP level were risk factors that affect postoperative survival.

42,573 cases of hepatectomy in China: a multicenter retrospective investigation.

B cells have been reported to have a suppressive function in autoimmune diseases, which appears to require an increase of CD11b expression on B cells. However, little is known how CD11b is induced in B cells to play the function. In this study, we found that the high expression of CD11b in B cells occurred not only in the mucosal immune organs, but also in systemically immune organs such as the spleen during dextran sulfate sodium (DSS)-induced colitis. Since the inflammatory lesions in mouse models of inflammatory bowel disease (IBD) were revealed to be significantly hypoxic or even anoxic, the B cells from colitic mice Peyer's patches (PP) were investigated to express higher levels of hypoxia-inducible factor-1α (HIF-1α) than naïve B cells from wildtype (WT) mice. HIF-1α siRNA transfection or HIF-1α protein inhibition led to decreased CD11b expression at both the mRNA and protein levels in vitro. B cells with HIF-1α specific knockdown were then adoptively transferred to Rag-1 mice. The result displayed that CD11b expression was decreased in B cells and an exacerbated colitis occurred. The bio-informatics promoter analysis and ChIP assay showed that HIF-1α was the critical transcription factor for CD11b and cooperatively formed a complex with the p-STAT3 homodimers to bind onto hypoxia-responsive element (HRE) regions, which was guaranteed by MEK/ERK pathway activation and IL-10 secretion. In conclusion, our study demonstrated the key function of the hypoxia-associated transcription factor HIF-1α together with p-STAT3 in driving CD11b transcription in B cells and controlling B cell's protective activity in experimental inflammatory bowel disease (IBD).

Regulation of CD11b by HIF-1α and the STAT3 signaling pathway contributes to the immunosuppressive function of B cells in inflammatory bowel disease.

T follicular helper (T) cells are crucial for effective humoral immunity by providing the required signals to cognate B cells and promoting germinal center (GC) formation. Many intrinsic and extrinsic factors have been reported to be involved in the multistage, multifactorial differentiation process of T cells. By comparing gene expression between T cells and T1 cells based on published GEO data, we found selective and high expression of sclerostin domain-containing protein 1 (SOSTDC1) in T cells but not in T1 cells; however, it is unclear whether SOSTDC1 is important for the differentiation and/or function of T cells. Using a mouse model of acute lymphocytic choriomeningitis virus (LCMV) infection, we confirmed the selective expression of SOSTDC1 in T cells compared to that in T1 cells, but the ablation of SOSTDC1 did not affect T cell differentiation or effector function. Thus, our results indicate that the SOSTDC1 protein is merely a specific marker of T cells but does not play a functional role in the differentiation of T cells during acute viral infection.

Sclerostin domain-containing protein 1 is dispensable for the differentiation of follicular helper and follicular regulatory T cells during acute viral infection.

During tumorigenesis, tumor infiltrating regulatory T (Treg) cells restrict the function of effector T cells in tumor microenvironment and thereby promoting tumor growth. The anti-tumor activity of effector T cells can be therapeutically unleashed, and is now being exploited for the treatment of various types of human cancers. However, the immune suppressive function of Treg cells remains a major hurdle to broader effectiveness of tumor immunotherapy. In this article, we reported that the deletion of Bcl6 specifically in Treg cells led to stunted tumor growth, which was caused by impaired Treg cell responses. Notably, Bcl6 is essential in maintaining the lineage stability of Treg cells in tumor microenvironment. Meanwhile, we found that the absence of follicular regulatory T (Tfr) cells, which is a result of Bcl6 deletion in Foxp3 cells, was dispensable for tumor control. Importantly, the increased Bcl6 expression in Treg cells is associated with poor prognosis of human colorectal cancer and lymph node metastasis of skin melanoma. Furthermore, Bcl6 deletion in Treg cells exhibits synergistic effects with immune checkpoint blockade therapy. Collectively, these results indicate that Bcl6 actively participates in regulating Treg cell immune responses during tumorigenesis and can be exploited as a therapeutic target of anti-tumor immunity.

Bcl6 Preserves the Suppressive Function of Regulatory T Cells During Tumorigenesis.

Primary liver cancer, around 90% are hepatocellular carcinoma in China, is the fourth most common malignancy and the second leading cause of tumor-related death, thereby posing a significant threat to the life and health of the Chinese people.

Guidelines for the Diagnosis and Treatment of Hepatocellular Carcinoma (2019 Edition).

The efficient induction and long-term persistence of pathogen-specific memory CD8 T cells are pivotal to rapidly curb the reinfection. Recent studies indicated that long-noncoding RNAs expression is highly cell- and stage-specific during T cell development and differentiation, suggesting their potential roles in T cell programs. However, the key lncRNAs playing crucial roles in memory CD8 T cell establishment remain to be clarified. Through CD8 T cell subsets profiling of lncRNAs, this study found a key lncRNA-Snhg1 with the conserved naive-effector-memory expression pattern in CD8 T cells of both mice and human, that can promote memory formation while impeding effector CD8 in acute viral infection. Further, Snhg1 was found interacting with the conserved vesicle trafficking protein Vps13D to promote IL-7Rα membrane location specifically. With the deep mechanism probing, the results show Snhg1-Vps13D regulated IL-7 signaling with its dual effects in memory CD8 generation, which not just because of the sustaining role of STAT5-BCL-2 axis for memory survival, but more through the STAT3-TCF1-Blimp1 axis for transcriptional launch program of memory differentiation. Moreover, we performed further study with finding a similar high-low-high expression pattern of human SNHG1/VPS13D/IL7R/TCF7 in CD8 T cell subsets from PBMC samples of the convalescent COVID-19 patients. The central role of Snhg1-Vps13D-IL-7R-TCF1 axis in memory CD8 establishment makes it a potential target for improving the vaccination effects to control the ongoing pandemic.

Zhiming Wang

Institute of Immunology

Third Military Medical University

Tumor Transplantation for Assessing the Dynamics of Tumor-Infiltrating CD8⁺ T Cells in Mice

Zhiming Wang

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Institute of Immunology

Third Military Medical University

Tumor Transplantation for Assessing the Dynamics of Tumor-Infiltrating CD8+ T Cells in Mice

Institute of Immunology

Tumor Transplantation for Assessing the Dynamics of Tumor-Infiltrating CD8⁺ T Cells in Mice