1.Role of IgG receptor FcγRⅡB in regulating neuronal damage and Th17/Treg immune balance in experimental autoimmune encephalomyelitis
Linting XIAO ; Shaolong ZHOU ; Hui ZHOU ; Yiqiu CAI ; Wei CHEN ; Peng LI
Chinese Journal of Immunology 2024;40(5):1030-1035,1041
Objective:To explore effect of IgG receptor FcγRⅡB on neuronal injury and imbalance of Th17/Treg in experi-mental autoimmune encephalomyelitis(EAE)model mice.Methods:C57BL/6 mice were randomly divided into control group,EAE group,FcγRⅡB group and EAE+FcγRⅡB group,with 15 mice in each group.EAE model was induced by subcutaneous injection of MOG35-55 peptide and treated with FcγRⅡB lentiviral solution.After modeling was established,body weight of mice was weighed every day,and neurological function was scored for 30 d;after 30 days,mice were sacrificed.HE staining was used to observe patho-logical changes of brain tissue,LFB staining was used to assess structural changes of spinal cord myelin,and immunofluorescence staining was used to detect spinal cord cerebral cortex neuron nuclear antigen(NeuN)and Caspase-3 expressions,TUNEL staining was used to detect apoptosis of neurons,ELISA was used to detect serum IL-6,IL-17,IL-10 and TGF-β levels,flow cytometry was used to analyze proportion of Th17 and Treg cells in spleen,Western blot was used to determine protein expressions of retinoic acid-related orphan receptor γt(RORγt)and Forkhead family transcription factor 3(Foxp3)in spinal cord tissue.Results:Compared with control group,mice in EAE group had decreased body weight,increased neurological function scores,obvious infiltration of inflamma-tory cells in brain tissue,and signs of demyelination in spinal cord,fluorescence expression intensity of NeuN was weakened and fluorescence expression intensity of Caspase-3 was enhanced,there were more TUNEL-positive stained cells,number of apoptotic cells was increased,levels of IL-6 and IL-17 in serum were increased,and levels of IL-10 and TGF-β were decreased,proportion of Th17 cells in spleen was increased,proportion of Treg was decreased,expression of RORγt protein in spinal cord tissue was up-regu-lated while relative expression of Foxp3 protein was down-regulated(P<0.05);compared with EAE group,weight of mice in EAE+FcγRⅡB group was increased,neurological function score was decreased,infiltration of inflammatory cells in brain tissue was reduced,demyelination of spinal cord was improved,fluorescence expression intensity of NeuN was enhanced,and fluorescence expression intensity of Caspase-3 was weakened,there were fewer TUNEL-positive stained cells,number of apoptotic cells was decreased,levels of IL-6 and IL-17 in serum were decreased,while levels of IL-10 and TGF-β were increased,at the same time,proportion of Th17 cells in spleen was decreased and proportion of Treg was increased,expression of RORγt protein in spinal cord tissue was down-regulated,while expression of Foxp3 protein was up-regulated(P<0.05).Conclusion:FcγRⅡB has neuroprotective effect on EAE mice,and can reduce infiltration of inflammatory cells and demyelination in brain tissue,whose mechanism may be related to regulation of cytokine levels and immune balance of Th17/Treg cells.
2.Effects of glucocorticoids on brain protection and cerebrospinal fluid immunoglobulin levels in rats with Streptococcus pneumoniae meningitis
Linting XIAO ; Shaolong ZHOU ; Hui ZHOU ; Yiqiu CAI ; Wei CHEN
Chinese Journal of Immunology 2024;40(6):1172-1177
Objective:To investigate the effect of glucocorticoids on brain injury in rats with Streptococcus pneumoniae(SP)meningitis,as well as the changes of cerebrospinal fluid immunoglobulin levels under this effect.Methods:A total of 40 SD rats were divided into control group,model group,low-dose methylprednisolone sodium succinate group(Low-MSS)and high-dose methylpred-nisolone sodium succinate group(High-MSS)according to random table method,with 10 rats in each group.Except for the control group,SP meningitis models were established in other groups.Rats in Low-MSS group and High-MSS group were injected with methyl-prednisolone sodium succinate by tail vein at doses of 5 mg/kg and 10 mg/kg,respectively,once a day for 21 days.Neurobehavioral scores of rats after modeling were performed by Loeffler method;contents of immunoglobulin IgA,IgM and IgG in cerebrospinal fluid of rats were detected by immunoturbidimetry;levels of inflammatory cytokines TNF-α,IL-6 and IFN-γ in supernatant of rats brain ho-mogenate were determined by ELISA;HE staining was used to detect pathological changes of rats brain tissue;Nissl staining was used to detect the number of neuronal cells in rats brain tissue;TUNEL staining was used to detect the number of apoptotic cells in rats brain tissue;immunofluorescence staining was used to detect expressions of GFAP and S-100b,the marker proteins of rat brain tissue injury.Results:Before SP injection,there was no difference in neurobehavioral scores between control group and model group(P>0.05),at 24 h,48 h and 72 h after SP injection,neurobehavioral scores in model group were significantly lower than those in control group(P<0.05).Compared with control group,contents of IgA,IgM and IgG in cerebrospinal fluid of rats in model group were in-creased,and contents of TNF-α,IL-6 and IFN-γ in supernatant of the brain homogenate were also increased,the tissue was obviously damaged,accompanied by a large number of inflammatory cells infiltration,the number of neuronal cells were decreased,the number of apoptotic cells were increased,and the fluorescence density values of S-100b and GFAP were increased(P<0.05);compared with model group,contents of IgA,IgM and IgG in cerebrospinal fluid of rats in Low-MSS group and High-MSS group were decreased,and contents of TNF-α,IL-6 and IFN-γ in brain homogenate supernatant were also decreased(P<0.05),brain tissue damage was alleviated,inflammatory cell infiltration was significantly reduced,neuronal cells were increased,the number of apoptotic cells were decreased,and the fluorescence density values of S-100b and GFAP were also decreased(P<0.05).In addition,the improvement effect of various indexes and brain tissue damage in High-MSS group was better than that in Low-MSS group,and the difference were statistically signifi-cant(P<0.05).Conclusion:Glucocorticoid methylprednisolone sodium succinate can effectively improve the brain tissue damage in SP meningitis rats,regulate the levels of immunoglobulin IgA,IgM and IgG,and has a protective effect on SP meningitis rats.
3.TRPC6 involves in endoplasmic reticulum stress induced apoptosis of glomerular mesangial cells
Linting WEI ; Pengbo GE ; Xiaoqin MA ; Jie GAO ; Dan LIU ; Peng ZHAO ; Shizhuo WEI ; Jing DONG ; Li WANG ; Rongguo FU
Journal of Xi'an Jiaotong University(Medical Sciences) 2023;44(6):898-903
【Objective】 To explore the role and mechanism of TRPC6 in apoptosis of glomerular mesangial cells (HBZY-1) induced by endoplasmic reticulum stress (ERS). 【Methods】 The experiment groups were classified as follows: normal control (NC), thapsigargin (TG), TG+SKF96365, and TG+TRPC6 siRNA groups. Transcription and protein expressions of TRPC6 and ERS related proteins (GRP78 and Caspase12) were detected by qRT-PCR and Western blotting. Additionally, cell apoptosis was measured by flow cytometry and Hoechst33258. Finally, Fluo-4 AM Ca2+ imaging technique was used to determine changes of intracellular calcium ( [Ca2+] i) by laser scanning confocal microscope. 【Results】 Morphological changes of apoptotic cells were characterized by nuclear enrichment or nuclear fragmentation, and the apoptosis rate was increased after TG stimulation. The expressions of TRPC6 and ERS related proteins (GRP78 and Caspase12) were elevated in TG group compared with NC group (P<0.05). Pre-incubation of HBZY-1 cells with SKF96365 and TRPC6 siRNA decreased cell apoptosis (P<0.05). The entry of [Ca2+] i also increased after TG stimulation (P<0.05). The expressions of TRPC6, GRP78 and Caspase12 were downregulated compared with TG group after treatment with SKF96365 and TRPC6 siRNA accompanied by decreased [Ca2+] i (P<0.05). 【Conclusion】 Taken together, this study suggests that inhibition of TRPC6 can alleviate TG-induced HBZY-1 cell apoptosis.
4.Mechanism of TRPC in promoting extracellular matrix deposition of glomerular mesangial cells
Linting WEI ; Pengbo GE ; Ke LI ; Yan LI ; Yinhong WANG ; Weihao ZHAO ; Chenkai CUI ; Jing DONG ; Jie GAO ; Li WANG ; Rongguo FU
Journal of Xi'an Jiaotong University(Medical Sciences) 2023;44(4):518-524
【Objective】 To explore the role and mechanism of TRPC in promoting extracellular matrix (ECM) deposition in rat glomerular mesangial cells (HBZY-1). Methods Immunofluorescence staining was performed to observe the distribution and expression of TRPC1 and TRPC6 in HBZY-1 cells. After AngⅡ stimulation, qRT-PCR and Western blotting were used to detect the mRNA and protein expressions of Gαq/PLCβ4/TRPC signaling pathway main proteins and ECM deposition indicators (α-SMA, collagenⅢ and fibronectin). By silencing the expressions of TRPC1 and TRPC6 by RNA interference, the expressions of ECM deposition indicators were detected. Changes in [Ca2+]i influx were determined through Fluo-4AM Ca2+ imaging. 【Results】 Both TRPC1 and TRPC6 were expressed in HBZY-1, and were mainly located in cell membrane and cytoplasm. After AngⅡ stimulation, Gαq/PLCβ4/TRPC signaling pathway was activated, and the mRNA and protein expressions of Gαq, PLCβ4, TRPC1 and TRPC6 were all increased (P<0.05). [Ca2+]i influx also increased (P<0.01), and the mRNA and protein expressions of ECM deposition indicators (α-SMA, ColⅢ and Fn) were upregulated (P<0.05). Silencing the expressions of TRPC1 and TRPC6 by RNA interference led to decreased [Ca2+]i influx (P<0.05), and downregulated mRNA and protein expressions of ECM deposition indicators in HBZY-1 cells (P<0.05). The results suggested that inhibition of TRPC expressions could inhibit AngⅡ induced ECM deposition in HBZY-1 cells, which might be associated with decreased [Ca2+]i influx. 【Conclusion】 TRPC may be a novel therapeutic target of renal fibrosis.
5.Diagnosis and treatment recommendations of dialysis patients with SARS-CoV-2 infection for primary care clinicians
Rongguo FU ; Zhao CHEN ; Lining JIA ; Li WANG ; Jin HAN ; Lifang TIAN ; Xianghui CHEN ; Linting WEI ; Fuqian LEI ; Jiamei LU ; Xiaoqin MA ; Li ZHAO ; Shizhuo WEI ; Jing LIU ; Zhaoyang DUAN ; Jie GAO
Journal of Xi'an Jiaotong University(Medical Sciences) 2023;44(3):353-360
End-stage renal disease (ESRD) patients undergoing outpatient hemodialysis (HD) and home peritoneal dialysis (PD) are high risk population of severe and critical types caused by SARS-CoV-2 infection. In order to improve the quality of diagnosis and treatment in dialysis patients with SARS-CoV-2 infection, we wrote this recommendation for primary care clinicians. During the epidemic period of SARS-CoV-2 infection, all patients should be instructed to strengthen self-management. Once the SARS-CoV-2 infection was found in dialysis patients, early stratified management should be carried out within 72 hours after the first positive nucleic acid or antigen test results, which includes early antiviral therapy, early recognition, and transferring severe patients from community or primary hospital to a referral hospital promptly. Guidance for dietary and sports rehabilitation after SARS-CoV-2 infection should also be started as soon as possible.