Objective To elucidate the expression diversity of IL-2R subunits in T helper(Th) cells under different activation condition and clarify its relationship with the response to IL-2 induced proliferation.Methods In vitro cultured Th1 cells were activated by plate bound anti-mouse CD3 McAb.In both activated and inactivated Th1 cells the expression of different IL-2R subunit was evaluated by real-time PCR and fluorescence staining,3H incorporation assay was adopt to measure the proliferation of the cells in response to IL-2 treatment,IL-2 affinity was determined via I125 labeled IL-2.IL-2Rα siRNA transfection was applied to knockdown CD25 expression in activated Th1 cells and its effect was confirmed by Western blot,IL-2 induced proliferation in IL-2Rα siRNA transfected Th1 cells were subsequently detected.CD4 cells were isolated from na(i)ve BALB/c mice and were also stimulated by plate bound anti-CD3 McAb.Cells were harvested at different days posterior to the stimulation,CD25 content and IL-2 induced proliferation were determined by flow cytometry and 3H incorporation assay respectively.Results In comparison with inactivated cells,only the expression of CD25but not other IL-2R subunits was significantly increased in activated Th1 cells.In accordance with elevated CD25,IL-2 affinity was also increased in activated Th1 cells,however,which resulted in decreased cell proliferation in response to IL-2 treatment.In activated Th1 cells,when CD25 expression was differently knockdown by different-dosed IL-2Rα siRNA transfection,the highest IL-2 response was observed in the cells with partially CD25 depression.Forin vitro activated na(i)ve CD4 cells the elevated CD25 expression gradually decreased and the highest proliferation response was detected at day 8 post stimulation upon IL-2 treatment.Conclusion Although CD25 is necessary for IL-2 induced proliferation,however,the excessively expressed CD25 lead to lower proliferation response.Not fully activated Thl or CD4 cells,but partially activated cells with lightly increased CD25 content possessed highest proliferation rate in response to IL-2 treatment.

BACKGROUND:Some studies have shown that the hounsfield units(HU)value based on lumbar CT can be used to screen osteoporosis.At present,the number of patients with pulmonary infection has increased;the number of patients with pulmonary infection and type 2 diabetes is also increasing,which increases the utilization rate of chest CT. OBJECTIVE:To investigate the role of lumbar 1 vertebral body HU value based on chest CT in the screening of type 2 diabetes mellitus osteoporosis. METHODS:The clinical data of 244 patients with type 2 diabetes mellitus treated in the First Affiliated Hospital of Chengdu Medical College from June 2020 to June 2022 were analyzed retrospectively.The bone mineral density was obtained by dual-energy X-ray absorptiometry.According to WHO's diagnostic criteria for osteoporosis,the subjects were divided into the non-osteoporosis group(n=120)and the osteoporosis group(n=124).The general condition,T value and HU value of lumbar 1 vertebra in chest CT were compared,and the relationship between the HU value and T value of each position was analyzed and the accuracy of type 2 diabetes mellitus osteoporosis was evaluated. RESULTS AND CONCLUSION:(1)There was no significant difference in sex,age,body mass index,glycosylated hemoglobin,mean blood glucose,calcium(Ca),phosphorus(P),time of type 2 diabetes mellitus,history of hypertension and history of hyperlipidemia between the two groups(P>0.05).(2)The HU value was positively correlated with the lowest T value of the hip(r=0.619,P<0.01);the HU value was positively correlated with the hip T value(r=0.584,P<0.01),and the HU value was positively correlated with the femoral neck T value(r=0.641,P<0.01).When the HU value was 98,the prediction of type 2 diabetes mellitus osteoporosis had good accuracy,and the sensitivity was 70.8%.(3)It is concluded that the HU value of the lumbar 1 vertebra based on chest CT examination is of good value for osteoporosis screening in patients with type 2 diabetes mellitus,and may be an opportunistic and cost-free supplementary screening method for type 2 diabetes mellitus osteoporosis.

Immunogenic cell death (ICD) plays a major role in cancer immunotherapy by stimulating specific T cell responses and restoring the antitumor immune system. However, effective type II ICD inducers without biotoxicity are still very limited. Herein, a tentative drug- or photosensitizer-free strategy was developed by employing enzymatic self-assembly of the peptide F-pY-T to induce mitochondrial oxidative stress in cancer cells. Upon dephosphorylation catalyzed by alkaline phosphatase overexpressed on cancer cells, the peptide F-pY-T self-assembled to form nanoparticles, which were subsequently internalized. These affected the morphology of mitochondria and induced serious reactive oxygen species production, causing the ICD characterized by the release of danger-associated molecular patterns (DAMPs). DAMPs enhanced specific immune responses by promoting the maturation of DCs and the intratumoral infiltration of tumor-specific T cells to eradicate tumor cells. The dramatic immunotherapeutic capacity could be enhanced further by combination therapy of F-pY-T and anti-PD-L1 agents without visible biotoxicity in the main organs. Thus, our results revealed an alternative strategy to induce efficient ICD by physically promoting mitochondrial oxidative stress.