AIM:To investigate the influence and mechanisms of human pancreatic cancer tumor microenvironments on T-cell immunoglobulin mucin-3 (TIM-3) expression and function of dendritic cells (DCs).METHODS:Tumor-infiltrating dendritic cells (TIDC) and para-carcinoma tissue DCs were isolated by Ficoll-Hypaque density centrifugation from trypsinized pancreatic carcinoma tissues, and the peripheral blood mononuclear cells were isolated from pancre-atic cancer patients or healthy people.The expression of TIM-3 on DCs was detected by flow cytometry.DCs isolated from healthy people peripheral blood mononuclear cells were induced by rhGM-CSF and IL-4.The expression of TIM-3 in the DCs treated with the culture supernatants of Capan-2, SW1990 and Panc-1 pancreatic cancer cells or human skin fibroblast (Hs27) cells for 48 h, and in the DCs treated with supernatants of Capan-2 cells, anti-VEGF-R2, anti-IL-10 and EP2 re-ceptor blocking peptide were evaluated by flow cytometry.The releases of IFN-βand IL-12 in the culture supernatants of DCs pretreated with monoclonal antibody ( mAb) to TIM-3 or DNase+RNase, followed by stimulation with apoptotic Ca-pan-2 cells, were detected by ELISA.RESULTS:DCs in tumor microenvironments had higher expression of TIM-3 than the DCs from para-carcinoma tissues and pancreatic cancer patient or healthy people peripheral blood ( P<0.01 ) .TIM-3 expression in the DCs treated with the culture supernatants of Capan-2, SW1990 and Panc-1 pancreatic cancer cells for 48 h was much higher than that in Hs27 cells (P<0.05).Treatment with a combination of anti-VEGF-R2, anti-IL-10 and EP2 receptor blocking peptide largely diminished the upregulation of TIM-3 on the DCs mediated by Capan-2 cell superna-tants (P<0.05).The concentrations of IFN-βand IL-12 in the DCs with high expression level of TIM-3 were lower than those in the DCs with low TIM-3 expression level.Treatment with mAb to TIM-3 resulted in much more IFN-βand IL-12 releases (P<0.01), but DNase+RNase made this effect disappear.CONCLUSION:TIM-3 serves as a negative regula-tor of DCs innate immune responses in the pancreatic cancer microenvironments.The secretion of soluble factors to tumor microenvironment by pancreatic cancer cells, including IL-10, VEGF and PGE2 , may contribute to the regulation of TIM-3 expression.

Objective To evaluate the protective effectiveness of intranasal immunizations with recombinated-pneumococcal autolysin(Re-LytA), which protects mice against local and systemic Streptococ- cus pneumoniae(Sp) infection. Methods Testing group (group A): CpG as an adjuvant, the mice were intranasally immunized with purified Re-LytA, obtained by affinity chromatograph. The negative control group(group B) were intranasally immunized with sterile saline. And the positive control group (group C) were received 23-valent polysaccharide commercial vaccine through intramuscular injection. All the samples were collected 2 weeks post the last immunization. The levels of antibody was determined by ELISA. Then the mice were challenged intraperitoneally and intranasally with Sp, respectively. The infection and coloniza- tion was followed by monitoring colony-forming units of Sp in the blood, homogenized lung, and nasopharyn- geal lavage fluid 4 days post intranasal immunization. The mice were observed daily to note the livability of each group. Results The level of the LytA antibody (IgG, IgA, slgA) in group A were higher than that in group B and C (P < 0.05). Neither the LytA nor polysaccharide antibody could be detected in group B. Polysaccharide antibody could be detected in group C. After challenged intraperitoneally there was no signifi- cant difference in survival rates between group A and group C (P > 0.05), which was significant higher than that in group B (P <0.05). After challenged intranasally, compared with the group A, the geometric mean colony-forming units washed from the nasopharyngeal lavage fluid of the group B and group C were signifi- cantly higher (P <0.05). Conclusion lntranasal immunizations with Re-LytA can protect mice against lo- cal and systemic pneumococcal infection, and the protective immunity may be related to sIgA.

To characterize the CD45RA+and CD45RO+T lymphocyte subsets in the peripheral blood of patients with cGVHD induced by allogeneic haematopoietic stem cell transplantation ( allo-HSCT ) and to explore their relations with the disease.Methods:The peripheral blood was collected from 64 patients after allo-HSCT,including 21 non-cGVHD patients,15 light grade cGVHD patients,18 mild grade cGVHD patients and 10 severe grade cGVHD patients,then CD4+CD45RA+,CD4+CD45RO+, CD8+CD45RA+and CD8+CD45RO+T lymphocyte subsets were detected by flow cytometry ( FCM).Results: Compared with the control,the percent of CD4+CD45RA+T lymphocyte in patients with light,mild and severe grade cGVHD decreased markedly (P<0.05),the percent of CD4+CD45RO+T lymphocyte increased markedly (P<0.05).But there were not obviously change in the patient with different grade cGVHD.The percent of CD8+CD45RA+,CD8+CD45RO+T lymphocyte did not change obviously.Conclusion:CD4+CD45RA+and CD4+CD45RO+may play an important role in the pathogenesis of cGVHD.