Objective To observe the role of human hepatocarcinoma HepG2 cell culture supernatant on T lymphocyte of the activation, proliferation, IL-2 secretion and inducing apoptosis in vitro. To explore the mechanism of immune escape in tumor.Methods Peripheral blood mononuclear cells (PBMC) were cultured with different concentration of tumor cell culture supernatant. Cell proliferation was examined with standard cytometry and MTT. The apoptotic rate and immune phenotype were analyzed by FACS. The level of IL-2 was determined with ELISA.Results Adding HepG2 supernatant, there was no significant influence in activation of lymphocyte, but the proliferation rat and the secretion of IL-2 were obviously decreased. The lymphocyte apoptosis rate was raised.Conclusion The tumor cell may produce a certain soluble protein, thus escape from the immune surveillance of tumor-bearing host.

0.05),but the proliferation rate(P

Objective To investigate the proliferative response of peripheral blood mononuclear cells(PBMC) and its depressant effect on small cell lung cancer(SCLC)cells(H446) in patients with paraneoplastic neurological syndrome(PNS).Methods PBMC of 7 patients with PNS and 6 patients with SCLC were cultured with interleukin(IL)-2 in vitro,then cultured separately or mixed with H446 respectively.The proliferation index(PI,the ratio of cellular score which had proliferated and that had not proliferated) of H446,PBMC,CD4+,CD8+ T cell and the ratio of CD4+,CD8+,CD4+/CD8+ were analyzed with flow cytometry and compared with normal control group.Results Compared with cultured separately,the PI of H446,PBMC,CD4+,CD8+T cell in PBMC of PNS and SCLC groups cultured with H446 were not significantly different.Stimulated by IL-2,the ratio of CD4+ T cell in PNS patients [(76.54 ? 3.96)%]was higher than that in normal control group[(51.75 ? 17.3)%](P

Objective:To explore the role of CD28 in the activation of human peripheral blood ?? +T cells by Mycobacterium tuberculosis (Mtb) low molecular peptide antigen in vitro Methods:Mtb antigen and anti CD28 monoclonal antibody (mAb) were used as signal 2 to stimulate the r? + T cell from PBMC the expression of CD28 molecule on ?? +T cells, proliferation rate of ?? +T cells and expression of CD69 molecule on activated ?? +T cells were analyzed by using flow cytometry Results:CD28 molecule was expressed on 50% of ?? +T cells Neither Anti CD28 nor Mtb antigen alone, but both presence, could stimulate ?? +T cells activation and proliferation CD69 molecule was expressed on activated ?? + T cells.Conclusion:The CD28 molecule could provide the costimulatory signal in the full activation of ?? +T cells by Mtb low molecular peptide antigen CD69 molecule was also an early activation marker of ?? +T cells

BACKGROUND:Previous study has observed that the calf acellular dermal membrane exhibits slow repair efficiency, fast degradability speed and other shortcomings in the repair of cartilage defects. OBJECTIVE:To investigate the repair effect of the col agen type Ⅱ-modified acel ular dermal membrane on cartilage defects in rabbits. METHODS:The fetal rabbit chondrocytes were seeded onto the col agen type Ⅱ-modified acel ular dermal membrane, and the composite was then observed under scanning electron microscope at 3, 7 and 14 days. Cartilage defect models were established on the bilateral femoral condyles of 24 New Zealand white rabbits, and these model rabbits were randomly allocated to three groups. The cartilage-acellular dermal membrane and cartilage-collagen type Ⅱ-modified acellular dermal membrane were implanted into the defect regions of control and experimental groups, respectively. Those received no intervention were as blank control group. Collagen type Ⅱ immunohistochemical staining and Wakitani scoring system were performed at 6 and 12 weeks postoperatively. RESULTS AND CONCLUSION:Chondrocytes grew and adhered well in the scaffold. The Wakitani scores in the experimental group were significantly lower than those in the control and blank control groups at postoperative 6 and 12 weeks (P<0.05). At 6 and 12 weeks postoperatively, collagen type Ⅱ immunohistochemical staining was the strongest in the experimental group, with yellow and brown particles in the cytoplasm;the control group was positive for collagen type Ⅱ immunohistochemical staining, while the blank control group was negative for the staining. Our findings suggest that the collagen type Ⅱ-modified acellular dermal membrane is beneficial for the repair of cartilage defects.

BACKGROUND:No method is ideal for treating traumatic avascular necrosis of talus up to now.Extracorporeal shock wave therapy(ESWT)is a micro-traumatic,simple,and effective method to treat musculoskeletal diseases;however,the therapeutic effect on necrosis of talus needs to be further studied.OBJECTIVE:To evaluate the therapeutic effect of liquid-electric extracorporeal shock wave on traumatic avascular necrosis of talus,and to explore new treatments of traumatic avascular necrosis of talus METHODS:A total of 34 patients with traumatic avascular necrosis of talus were selected from the Affiliated Hospital of Medical College of Chinese Armed Police Force from September 2004 to June 2009.The patients were randomly divided into ESWT and control groups,with 17 patients per group All patients were treated with pain point positioning combined with surface X-ray localization,theworking voltage of 8-10 kV,energyflowdensity of 0.12-0.16mJ/mm2,impact frequency of 40-50 times/min,and impact of 800-1000 times,once a week,for 3-5 cycles.Pain was evaluated with VAS before and after treatment,function of ankle was evaluated with AOFAS standards,and MRI of ankle was re-checked at 18 months after treatment to compare necrotic area before and after treatment.RESULTS AND CONCLUSION:VAS pain,function of ankle,and necrotic area of ankle in the ESWT group were significantly improved compared to those in the control group at 18 months after treatment(P<0.01).Activity of one case in the control group was limited by severe pain due to traumatic arthritis in the first 15 weeks after ankle arthrodesis surgery.This suggested that significant effect and fewer complications,for treating traumatic avascular necrosis of talus.

Objective:To observe the stimulating effect of C main Peptide purified from Mycobacterium tuberculosis peptide antigens(Mtb Ag) on human ??T cells, and the effect of C main peptide on the Mtb Ag activated ??T cells in vitro. Methods:C main peptide was used to stimulate fresh ??T cells of normal subjects in different doses for 10 d and the responded cells were phenotyped by flow cytometry. Furthermore,C main peptide was used to restimulate the activated ??T cells ,and then analyse the expression of early activation marker molecule CD69 in ??T cells by flow cytometry and the activity of proliferation of ??T cells by MTT assay. Results:C main peptide could stimulate the proliferation of fresh ??T cells predominantly, and it also could promote the expression of CD69 in activated ??T cells and enhance its activity of proliferation. Conclusion:C main peptide purified from Mtb Ag is a kind of specific stimulator of human ??T cell in vitro.

Objective:Some antigens of M.tb to culture with peripheral blood mononuclear cells ( PBMC) for assaying their proliferation and activation,so as to signify whether lipid antigens of M.tb have specific immune responses in host against M.tb infection or not.Methods:We treated PBMC with several lipid antigens of M.tb to explore the ability of these antigens to activate immunity in healthy individuals.We measured and analyzed cell proliferation by labeling cells with carboxyfluorescein succinimidyl amino ester (CFSE) and subjecting them to flow cytometry (FCM).The production of IFN-γ,TNF-αand IL-4 by T cell subsets (NKT,CD4+, CD8+,andγδT) from healthy donors was analyzed by FCM after stimulation with autologous immature dendritic cells pre-cultured with M.tb lipid antigens.The tested M.tb lipid antigens were the total lipid (TLIP),Acetone-Soluble Lipids (ASLIP),Purified Sulfolipid (PSLIP),Lipoarabinomannan (LAM) and Lipomannan (LM) levels.Medium free of lipid antigens(WCL,CFP,LPS,Mtb-HAg and blank) was used as a control.Results:We found the proportion of proliferative NKT and CD8+T cells significantly increased in all lipid groups (P<0.05).ASLIP,LAM and LM promoted non-proliferative CD4+T cells to secrete IL-4 and proliferative ones to secrete IFN-γ( P<0.05).All lipid antigens promoted both proliferativeγδT cells and CD8+T cells to secrete IFN-γand TNF-α,but the proportion of TNF-α-secreting cells in these populations decreased in the LM group ( P<0.05 ).Conclusion: Lipid antigens may affect the CD1-restricted T cells of the host to fight M.tb infection.

Objective:To understand whether there are drug resistant and disinfectant resistant Yersinia pestis strains in China, and to provide accurate information for clinical treatment of plague. Methods:A total of 2 753 Yersinia pestis strains isolated from 10 natural plague foci in China from 1943 to 2016 were collected. According to National Center for Biotechnology Information (NCBI) released sequences of aminoglycoside streptomycin resistant genes strA, strB, β-lactam antibiotics resistant genes TEM, SHV and CTX-M, sulfamilamide resistant genes sul1, sul2 and sul3, and disinfectant resistant gene qacE△1-sul1, a pair of primers of each gene was designed for above-mentioned genes. Genomic DNA of 2 753 strains of Yersinia pestis was extracted, and the 9 target genes of all DNA samples were amplified by PCR. Results:Negative and positive controls of PCR detection were established. No corresponding target bands of aminoglycoside streptomycin resistant genes strA, strB, β-lactam antibiotics resistant genes TEM, SHV and CTX-M, sulfamilamide resistant genes sul1, sul2 and sul3, and disinfectant resistant gene qacE△1-sul1 were found in the DNA samples of 2 753 strains of Yersinia pestis.Conclusion:The above-mentioned genes of drug resistance and disinfectant resistance have not been detected in Yersinia pestis of China, but the monitoring of drug resistance of Yersinia pestis still needs to be carried out continuously.

Objective To establishment a method for detection of multiple drug resistance gene of Yersina pestis using polymerase chain reaction(PCR), to provide a guidance for treatment of plague. Methods According to National Center for Biotechnology Information (NCBI) released sequences of aminoglycoside resistant genes of streptomycin resistant,strB,strA,beta lactam antibiotics resistant genes tem,shv,and ctx-m,sulfamilamide resistant genes sul1, sul2, and sul3, a pair of primers of each gene was designed. DNAs of 282 strains isolated from plague natural foci in Qinghai Province were amplified by PCR using every pair of primers. The products were separated using gel electrophoresis, and the results were visualized through a gel imaging system. The susceptibility of 282 Yersina pestis to streptomycin, sulfamethoxazole and ceftriaxone was tested by drug sensitivity test. Results The PCR amplification results of all samples were negative,and strains with streptomycin,sulfamilamide and beta lactam antimicrobial drug resistance genes were not found. Drug sensitivity test showed that 282 strains were highly sensitive to streptomycin,sulfamethoxazole and ceftriaxone sodium.The diameter of bacteriostasis ring>19,17,21 mm, respectively. Conclusions It is a feasible method to use PCR technology to detect the multiple drug resistance genes of Yersinia pestis. Using this method to systematically monitor the resistance gene of Yersinia pestis is an efficient, economical and practical experimental method, which can provide guidance for the treatment of plague disease.