T cell exclusion is crucial in enabling tumor immune evasion and immunotherapy resistance. However, the key genes driving this process remain unclear. We uncovered a notable increase of insulin-like growth factor 2 (IGF2) in immune-excluded tumors, predominantly secreted by cancer-associated fibroblasts (CAFs). Using mice with systemic or fibroblast-specific deletion of IGF2, we demonstrated that IGF2 deficiency enhanced the infiltration and cytotoxic activity of CD8 ⁺ T cells, leading to a reduction in tumor burden. Integration of spatial and single-cell transcriptomics revealed that IGF2 promoted interaction between CAFs and T cells via CXCL12 and programmed death ligand 1 (PD-L1). Mechanistically, autocrine IGF2 activated PI3K/AKT signaling by binding to the IGF1 receptor (IGF1R) on CAFs, which was required for the immunosuppressive functions of CAFs. Furthermore, genetic ablation of IGF2 or targeted inhibition of the IGF2/IGF1R axis with the inhibitor linsitinib markedly boosted the response to immune checkpoint blockade. Clinically, elevated levels of IGF2 in tumors or plasma correlated with an adverse prognosis and reduced efficacy of anti–programmed death 1 treatment. Together, these results highlight the pivotal role of IGF2 in promoting CAF-mediated immunoevasion, indicating its potential as a biomarker and therapeutic target in immunotherapy.

Background: Breast cancer is a complex disease with a highly immunosuppressive tumor microenvironment, and has limited clinical response to immune checkpoint blockade (ICB) therapy. T-helper 2 (Th2) cells, an important component of the tumor microenvironment (TME), play an essential role in regulation of tumor immunity. However, the deep relationship between Th2-mediated immunity and immune evasion in breast cancer remains enigmatic. Methods: Here, we first used bioinformatics analysis to explore the correlation between Th2 infiltration and immune landscape in breast cancer. Suplatast tosilate (IPD-1151 T, IPD), an inhibitor of Th2 function, was then employed to investigate the biological effects of Th2 blockade on tumor growth and immune microenvironment in immunocompetent murine breast cancer models. The tumor microenvironment was analyzed by flow cytometry, mass cytometry, and immunofluorescence staining. Furthermore, we examined the efficacy of IPD combination with ICB treatment by evaluating TME, tumor growth and mice survival. Results: Our bioinformatics analysis suggested that higher infiltration of Th2 cells indicates a tumor immunosuppressive microenvironment in breast cancer. In three murine breast cancer models (EO771, 4T1 and EMT6), IPD significantly inhibited the IL-4 secretion by Th2 cells, promoted Th2 to Th1 switching, remodeled the immune landscape and inhibited tumor growth. Remarkably, CD8⁺ T cell infiltration and the cytotoxic activity of cytotoxic T lymphocyte (CTL) in tumor tissues were evidently enhanced after IPD treatment. Furthermore, increased effector CD4⁺ T cells and decreased myeloid-derived suppressor cells and M2-like macrophages were also demonstrated in IPD-treated tumors. Importantly, we found IPD reinforced the therapeutic response of ICB without increasing potential adverse effects. Conclusions: Our findings demonstrate that pharmaceutical inhibition of Th2 cell function improves ICB response via remodeling immune landscape of TME, which illustrates a promising combinatorial immunotherapy.

Sepsis is a life-threatening syndrome characterized by organ dysfunction caused by a dysregulated host response to infection. Sepsis-associated acute liver injury (SA-ALI) is a frequent and serious complication of sepsis that considerably impacts both short-term and long-term survival outcomes. In intensive care units (ICUs), the mortality rate of patients with SA-ALI remains high, mostly due to the absence of effective early diagnostic markers and suitable therapeutic strategies. Recent studies have demonstrated the importance of non-coding RNAs (ncRNAs) in the development and progression of SA-ALI. This review focuses on the critical roles of ncRNAs, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), in regulating "cytokine storms", oxidative stress, mitochondrial dysfunction, and programmed cell death in SA-ALI, and summarizes the current state and limitations of existing studies on lncRNAs and circRNAs in SA-ALI. By integrating advancements in high-throughput sequencing technologies, this review provides novel insights into the dual potential of ncRNAs as diagnostic biomarkers and therapeutic targets, offers new ideas for SA-ALI diagnosis and treatment research and highlights potential challenges in clinical translation.

The impairment of immunity characterized by T cell exhaustion is the main cause of death in patients with sepsis after the acute phase. Although PD-1 blockade is highly touted as a promising treatment for improving prognosis, the role of PD-1 plays in sepsis and particularly its different roles in different periods are still very limited. A recent study revealed LAG3 can resist the therapeutic effect of PD-1 blockade in tumor, which inspired us to understand their role in sepsis. We enrolled 26 patients with acute sepsis from 422 candidates using strict inclusion criteria. Follow-up analysis revealed that the expression levels of PD-1 were rapidly increased in the early stage of sepsis but did not change significantly as infection continued (P < 0.05). However, the expression of LAG3 was contrary to that of PD-1. Compared with LAG3 or PD-1 single-positive T cells, T cells coexpressing LAG3 and PD-1 were significantly exhausted (P < 0.05). The proportion of coexpressing T cells was negatively correlated with the total number of lymphocytes (r = −0.653, P = 0.0003) and positively correlated with the SOFA score (r = 0.712, P < 0.0001). In addition, the higher the proportion of coexpressing T cells was, the longer the hospital stay and the higher the mortality. These results showed that LAG3 and PD-1 had a potential synergistic effect in regulating the gradual exhaustion of T cells in sepsis, which seriously affected the clinical prognosis of patients. Therefore, LAG3 and PD-1 double-positive T cells are an important indicator for immunity detection and prognostic evaluation. In the future, precision therapy may pay more attention to the different expression patterns of these two molecules.

Introduction: Adipose-derived mesenchymal stem cells (ADSCs) are promising candidates for mesenchymal stem cell (MSC) therapy due to their ease of isolation from the stromal vascular fraction (SVF) of adipose tissue. However, traditional isolation methods often result in mouse ADSCs with low purity and significant heterogeneity contributing to inconsistencies in results from preclinical and clinical studies. This is partly attributed to the lack of consensus on their surface markers.Methods: This study compared three purification methods for isolating mouse ADSCs based on Sca-1 positivity—direct adherence (ADSC-A), magnetic cell sorting followed by adherence (ADSC-M), and adherence to the third generation followed by magnetic cell sorting (ADSC-AM). Third-generation ADSCs were evaluated for proliferative activity, differentiation potential, and functional enrichment using proliferation assays, trilineage differentiation assays, and RNA sequencing. Flow cytometry was employed to assess Sca-1 positivity and the expression of positive (CD44, CD90, CD29) and negative markers (CD31, CD45) in the fourth-generation ADSCs.Results: Among the three methods, ADSC-AM exhibited superior properties, including uniform morphology, enhanced proliferation, and over 95% expression of Sca-1 and CD29. While all methods supported trilineage differentiation, ADSC-AM demonstrated enhanced adipogenesis. Furthermore, RNA sequencing and pathway enrichment analysis revealed that ADSC-AM possessed unique potential in angiogenesis and immune regulation.Discussion: These findings suggest that the ADSC-AM method offers a simple and reproducible approach for obtaining high-purity mouse ADSCs with better functional properties and provide a fundamental reference for understanding mouse ADSCs surface marker profiles.

Sepsis is a multisystem disease characterized by dysregulation of the host immune response to infection. Immune response kinetics play a crucial role in the pathogenesis and progression of sepsis. Macrophages, which are known for their heterogeneity and plasticity, actively participate in the immune response during sepsis. These cells are influenced by the ever-changing immune microenvironment and exhibit two-sided immune regulation. Recently, the immunomodulatory function of mesenchymal stem cells (MSCs) in sepsis has garnered significant attention. The immune microenvironment can profoundly impact MSCs, prompting them to exhibit dual immunomodulatory functions akin to a double-edged sword. This discovery holds great importance for understanding sepsis progression and devising effective treatment strategies. Importantly, there is a close interrelationship between macrophages and MSCs, characterized by the fact that during sepsis, these two cell types interact and cooperate to regulate inflammatory processes. This review summarizes the plasticity of macrophages and MSCs within the immune microenvironment during sepsis, as well as the intricate crosstalk between them. This remains an important concern for the future use of these cells for immunomodulatory treatments in the clinic.