Objective:To observe the expression of T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain(TIGIT)in tumor tissue and peripheral blood CD8+T cells in patients with triple-negative breast cancer(TNBC),and to explore the ef-fect of tiragolumab on the function of CD8+T cells in the peripheral blood of these patients.Methods:The expression of TIGIT in tumor tissue of patients with TNBC was analyzed using The Cancer Genome Atlas(TCGA)database and immunohistochemical staining.Flow cytometry was employed to assess the co-expression of TIGIT and programmed death-1(PD-1)in peripheral blood CD8+T cells,as well as their cytokine secretion.A co-culture model of CD8+T cells and TNBC cell lines,HCC-1937 and MDA-MB-231,was estab-lished.The effect of tiragolumab on the anti-tumor activity of CD8+T cells in patients with TNBC was investigated using flow cytometry and confocal fluorescence imaging.Results:The expression of TIGIT in tumor tissue and peripheral blood CD8+T cells of patients with TNBC was significantly increased(P<0.05).Compared with the healthy control group,the TNBC group showed a significantly larger number of TIGIT+PD-1+CD8+T cells in the peripheral blood and significantly reduced secretion of interferon gamma(IFN-γ),tumor necrosis factor-α(TNF-α),and ginkgolide B(GB)by CD8+T cells;specifically,TIGIT+CD8+T cells demonstrated significantly re-duced secretion compared with TIGIT-CD8+T cells(P<0.05).Fol-lowing treatment with tiragolumab,TIGIT+CD8+T cells exhibited increased secretion of IFN-γ and TNF-α(P<0.05).In the co-culture model,tiragolumab restored the apoptosis-inducing ability of CD8+T cells in patients with TNBC,and this ability was further enhanced when it was combined with envafolimab.Conclusion:Ti-ragolumab restores the tumor-killing function of CD8+T cells by im-proving their immunosuppression.The combination of tiragolumab with envafolimab can further enhance its anti-tumor effect.

ObjectiveTo investigate the mechanism of Lycium barbarum polysaccharides （LBP） in promoting the activation of RAW264.7 macrophages. MethodRAW264.7 macrophages were stimulated with LBP at different concentrations （50， 100， 200 mg·L^-1）， and those stimulated with lipopolysaccharide （LPS） at 100 μg·L^-1 and galactose （Gal） at 100 mg·L^-1 as positive controls. After 24 h of LBP stimulation， the cell counting kit-8 （CCK-8） was used to detect the survival rate of RAW264.7 macrophages treated with LBP （0， 50， 100， 200， 400， 800 mg·L^-1）. The levels of interleukin-6 （IL-6） and interleukin-12 （IL-12） in cell culture supernatant were detected by enzyme-linked immunosorbent assay （ELISA）. The protein and mRNA expression of p38 mitogen-activated protein kinase （MAPK）， extracellular signal-regulated kinase （ERK）， c-Jun N-terminal kinase （JNK）， and nuclear factor κB （NF-κB） in Toll-like receptor 4 （TLR4）/Toll-like receptor 2 （TLR2）/macrophage galactose-type lectin （MGL） pathway of RAW264.7 macrophages was detected by Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） and Western blot. ResultCCK-8 results showed that compared with the results in the blank group， the survival rate of RAW264.7 macrophages decreased in the 400， 800 mg·L^-1 LBP groups （P<0.05）. ELISA results showed that compared with the blank group， 50 mg·L^-1 LBP could promote the secretion of IL-12 in RAW264.7 macrophages （P<0.01）. Compared with the blank group， 100 mg·L^-1 LBP and 200 mg·L^-1 LBP could promote the secretion of IL-6 in RAW264.7 macrophages （P<0.05， P<0.01）. Western blot results showed that compared with the blank group， the LBP groups （50， 100， 200 mg·L^-1） enhanced protein expression levels of MAPK key molecules （p-p38 MAPK， p-ERK， p-NF-κB， and p-JNK） in TLR4， TLR2， and MGL pathways （P<0.05， P<0.01）. Compared with the model group， the 200 mg·L^-1 LBP group could promote the expression level of p-NF-κB protein in RAW264.7 macrophages （P<0.01）. Real-time PCR results showed that compared with the blank group， the LBP groups （50， 100， and 200 mg·L^-1） enhanced the mRNA expression levels of MAPK key molecules （p38 MAPK， ERK， NF-κB， and JNK） in TLR4 and TLR2 pathways （P<0.05， P<0.01）. Compared with the model group， the 50 and 200 mg·L^-1 LBP groups could promote the mRNA expression levels of JNK and ERK2 in RAW264.7 macrophages （P<0.05， P<0.01）. ConclusionLBP can regulate the activation of RAW264.7 macrophages and participate in the immune response through the TLR2/TLR4/MGL pathway.