Objective To study the research method of cell survival rate at the procedure of cryopreservation of tissue engineered tendons.Methods In the 4thgeneration of human fibroblasts, the dead cells were stained with propidium iodine (PI), while the living cells with Hoechst 33342(Ho). The living cells and dead cells emitted fluorescence of red and blue respectively after they were stimulated by suitable ultra-violet, then flow cytometry was applied to distinguishthem. The seeding cells were collected to make them to be the cell suspension of suitable concentration(6.0×105 cell/ml) before they were divided into two parts. We cryopreserved and defrosted one part three times to kill the cells and didnot cryopreserve the other part, then we made cell suspension at different ratios of cryopreserved cell to noncryopreserved cells. The fluorescence staining and flow cytometry were used to study the correlation between cell ratios of cryopreservedcell to non-cryopreserved cell and the cell survival rates. We compared the cll survival rates between immediate flow cytometry and that 2 hours after fluorescence staining. Results The results of flow cytometry showed that correlation between the ratio of cryopreservation and the cell survival rate was significant (r=0.970，Plt;0.05), image analysis study also showed the correlation was significant (r=0.982，Plt;0.05).The cell survival rate decreased by use of flow cytometry twohours after fluorescence staining, but there was no significant difference when compared with that of immediate flow cytometry (Pgt;0.05). We could also observe the cells on the tissue engineered tendons by fluorescence image directly.Conclusion Flow cytometry and fluorescence image afterPI and Ho staining is a good way in study cell survival rate at the procedure of cryopreservationof tissue engineered tendons.
Purpose
To investigate bax expression and induction of apoptosis in normal cultured retinal pigment epithelium (RPE) cells ．
Methods
Cultured human RPE cells were transfected by PMDNA3-hbax，which incoded the whole bax gene and may be induced by Zn2+ under the MTII promoter， through lepofectin mediated protocol．The tested RPE cells were divided into three groups of A，PMDNA3-hbax transfected ;B，PMDNA3 (nude vector) transfected and C ，normal RPE cells．After transfection， DNA gel electrophoreses were perform ed ，the tested RPE cell cycles were analyzed with flow cytometry (FCM)．
Results
The gel electrophoretogram showed DNA ladder phenomenon，FCM confirmed the apoptosis of RPE cells PMDNA3-hbaxtransfected ， consisting of significant apoptotic peak sited before the G 1 phase and the apoptotic rate was 36%．
Conclusion
The foreign bax gene can be effectively conducted in to the RPE cell through lepofectinmediated protocol and induced expression ． The foreign bax overexpression may induce the cultured human RPE cell susceptibi lity to apoptosis．
(Chin J Ocul Fundus Dis, 2001,17:132-134)
Objective
To examine the influence of retinal pigment epithelium(RPE) cells on antigen-specific activatedlymphocytes in vitro,and to explore the role of RPE cells in the immune privilege of the eye.
Methods
Co-culture systems of RPE cells with antigen-specific T lymphocyte lines and resting T lymphocytes were established in vitro．Induction of apoptosis was detected by genomic DNA electrophoresis,DNA in situ end-labelling and flow cytometry.
Results
RPE cells induced apoptosis in antigen-specific activated T lymphocytes. 24 hours after culture,the signs of apoptosis appeared in lymphocytes co-incubated with RPE cells．As time of co-culture went on,the number of apoptosic cells increased．Quantitative analysis of apoptosic cells showed that apoptosic cells accounted for 5.95% after 24 hours, 9.38% after 48 hours,and 17.95% after 72 hours．In contrast,RPE cells induced few apoptosis in resting T lymphocytes.
Conclusions
These results suggest that RPE cells possess the ability to induce the apoptosis of invading lymphocytes. This phenomenon serves as a restrain mechanism of immune response and may be of vital importance in the maintenance of immune privilege in posterior segment of eye and in the protection of eye from the damage of immunogenic inflammation.
(Chin J Ocul Fundus Dis, 1999, 15: 241-244)
Human SW480 colonic cancer cell line was evaluated for its growth response to pentagastrin, gastrin receptor antagonist proglumide (PGL) in vitro by MTT assay and flow cytometry. The results showed that gastrin possessed a proliferative effect on SW480 cell, PGL alone had no obvious effect on SW480 cell, but it inhibited gastrin-induced growth of SW480 cell with dosage dependent when it was used with gastrin, its inhibitive effect did not steadly increase at a dose＞32μg/ml. This suggests that effect of gastrin is achieved via gastrin receptor. Gastrin promoted the sythesis of DNA, protein and triggered the cancer cell shifting from phase G0/G1 to phase S, G2M. PLG inhibited the effect of gastrin, it suggests that gastrin possessed a proliferation on SW480 cell at post receptor is achieved by the effect of gastrin on cell cycle.
Objective To observe the proportion changes of CD4+CD25+FOXP3+ T cells in peripheral blood of patients with VogtKoyanagiHarada disease (VKH) before and after one month of treatment. Methods he peripheral blood samples from 15 patients with VKH disease before and after one month of treatment by glucocorticoid, and from 15 healthy volunteers were collected，and lymphocytes were separated from them. CD4+CD25+ regulatory T cells were labeled by antibodies of cell surface marker CD4、CD25 and transcription factor FOXP3. The proportion of CD4+CD25+FOXP3+ T cells were detected by flow cytometry. Results Before the treatment, the percentage of CD4+CD25+FOXP3+ T cells in periphery blood was（0.30plusmn;0.19）% of CD4+ cell in VKH patients, and（1.41plusmn;0.52）% in control group, the difference was statistically significant（t=7.665,Plt;0.01）; after one month of treatment, the VKH patients group was（1.28plusmn;0.54）% which close to the control group. However there were two patients whose CD4+CD25+ T cells increased extraordinarily after one month of treatment. Conclusions The proportion of CD4+CD25+ FOCP3+ T cells in periphery blood in VKH patients were lower than control group obviously before treatment, but were close to control group after treatment. Those results indicated that VKH diseases may be associated with the decreased proportion of CD4+CD25+ regulatory T cells.
Objective
To clarify the relationship between inhibition of proliferation and cxpression of Ki-67 in cultured human retinal pigment epithelial(RPE) cells.
Methods
The cultured human RPE cells were treated with daunoblastina at a dose of 180 mu;g/L for 12h.Twenty-four hours later,DNA inhibiting rate was studied by using tritium-labelled thymidine deoxyribose(3H-TdR)incorporation assay.The expression of Ki-67 was evaluated by immunocytochemical staining technique and image analysis system.Flow cytometry was used to analyse cell cycle.
Results
DNA inhibiting rate was directly proportional to the dosage of daunoblastina.The proportion of the cells positive staining to Ki-67 in the control and the daunoblastina-treated group were 89.3% and 45.6%(Plt;0. 01),and the integral optical density values for expression of Ki-67 in the two groups were 68.1plusmn;6.2 and 27.3plusmn;5.5(Plt;0.01),respectively.The percen tage of cells in G2 phase of cell cycle increased from 8.9% to 29.5%.
Conclusion
G2 block was induced and poliferation was inhibited by daunoblastina in cultured human RPE cells.There is a relatively good correlation between Ki-67 immunostaining and inhibition of RPE cell proliferation.
(Chin J Ocul Fundus Dis，2000，16：1-70)
Objective To investigate the changes of CD4 + CD25 + Foxp3 + regulatory T cells( Treg) in peripheral blood of patients with acute exacerbation of COPD( AECOPD) , and analyze the relationship of CD4 + CD25 + Foxp3 + Treg with insulin resistance. Methods A total of 79 patients with AECOPD were divided into four groups according to disease severity( 11 cases in stage Ⅰ,31 cases in stage Ⅱ,28 cases in stage Ⅲ, an 9 cases in stage Ⅳ) .42 healthy volunteers were recruited as control. Fast blood glucose( FBG) and fast insulin( FINS) were measured for calculating the insulin resistance index. The CD4 + CD25 + Foxp3 + Treg were detected by flow cytometry. The relationship between the proportion and number of CD4 + CD25 + Foxp3 + Treg with insulin resistance was statistically analyzed. Results Compared with the healthy control group, the levels of FBG, FINS, and insulin resistance index in the AECOPD patients were significantly higher ( P lt; 0. 01, P lt; 0. 05) . The proportion and number of CD4 + CD25 + Foxp3 + Treg in peripheral blood decreased significantly( P lt; 0. 01, P lt; 0. 05) . The insulin resistance index increased with the severity of AECOPD while the proportion and number of CD4 + CD25 + Foxp3 + Treg in peripheral blood decreased. The insulin resistance index in the AECOPD patients of stage Ⅲ and Ⅳ were higher than those of stage Ⅰ and Ⅱ. The proportion and number of CD4 + CD25 + Foxp3 + Treg in the AECOPD patients of stage Ⅲ and Ⅳ were significantly lower than those of stage Ⅰ and Ⅱ. Both the proportion and number of CD4 + CD25 + Foxp3 + Treg were negatively correlated with insulin resistance ( r = - 0. 633, - 0. 871, P lt; 0. 01) . Conclusions CD4 + CD25 + Foxp3 + Treg cells might may play important role in modulating insulin resistance in AECOPD. The more serious the disease, the lower the CD4 + CD25 + Foxp3 + Treg and the worse insulin resistance.
Objective To investigate the detection of peritoneal free cancer cells and its clinical significance. Methods The peritoneal free cancer cells, the positive rates of CK20 protein and CK20 mRNA expressions of peritoneal lavage fluid were detected by peritoneal lavage cytology (PLC), flow cytometry (FCM) and real-time fluorescent quantitative RT-PCR in 50 cases of gastric cancer patients, respectively. The sensitivity of three kinds of detection method to peritoneal free cancer cells was compared. Results The positive rates of peritoneal free cancer cells, CK20 protein and mRNA expression of peritoneal lavage fluid were 20.0% (10/50), 36.0% (18/50) and 58.0% (29/50), respectively. The positive rate of CK20 mRNA expression detected by real-time fluorescencequantitative RT-PCR in peritoneal lavage fluid was significantly higher than those of the CK20 protein expression detected by FCM and peritoneal free cancer cells detected by PLC (Plt;0.05 or Plt;0.001). The difference of positive rate of CK20 protein expression and peritoneal free cancer cells was not significant (Pgt;0.05). The positive rate of CK20 mRNA expression of peritoneal lavage fluid was related to the tumor invasion depth, differentiation degree, TNM stage, and lymph node metastasis (Plt;0.05). Conclusion Real-time fluorescence quantitative RT-PCR is an effective method for the detection of peritoneal free cancer cells.
Human SW480 colonic cancer cell line was evaluated for its growth response to Octa peptide somatostatin (SMS 201·995, SMS) in vitro by MTT assay and flow cytometry. The results showed that SMS possessed an inhibitive effect on SW480 cell at dose 1.563－200ng/ml, the maximal effective dose was 50ng/ml. Inhibitive effect of SMS did not steadily increase at a dose ＞50ng/ml. It suggests that effect of SMS is achieved via somatotatin receptor. SMS obviously inhibited the synthesis of DNA and protein, and prohibited the SW480 cell shifting from phase G0/G1 in phase S, G2M, which suggests that somatostatin (SS) possessed an inhibitive effect on large intestinal at cancer cell, it is achieved at receptor by inhibiting the synthesis of DNA and protein and prohibiting cell cycle of cancer.
Objective To investigate the value of a 4-color and 10-antibody flow cytometry immunophenotyping panel using 10 antibodies including CD45, CD38, CD19, CD56, CD20, CD5, CD10, human leukocyte antigen-DR (HLA-DR), κ antibody and λ antibody marked by four kinds of fluorescein including R-phycoerythrin (PE), fluorescein isothiocyanate (FITC), peridinin chlorophy Ⅱ protein (PerCP) and allophycocyanin (APC) in the diagnosis of multiple myeloma (MM). Methods A 4-color and 10-antibody flow cytometry immunophenotyping panel which used CD45dim/-/CD38high as gating strategy supplemented by CD19, CD56, CD20, CD10, CD5, HLA-DR, κ antibody and λ antibody was used to test the bone marrow (BM) specimens of 45 MM patients treated between December 2013 and March 2015. Then by morphological examination, we analyzed the quantitative results and characteristics of myeloma cells. Results In all the 45 MM patients, the myeloma cell detection rate was 100% by flow cytometry. The proportion range of myeloma cells in BM was between 1.17% and 72.31%, which showed a good consistency with the results of 7.5%-90.0% detected by morphological examination. The positive expression rates of antigen on myeloma cells were: 100.00% for CD38, 11.11% for CD45, 2.22% for CD19, 73.33% for CD56, 17.78% for CD20, 42.22% for HLA-DR, and 0% for CD10 and CD5. About 64.44% of the MM patients were restricted cytoplasmic λ light chain typing, and 35.56% were restricted cytoplasmic κ light chain typing. There was no obvious phenotype difference among the 3 Durie-Salmon stages of MM (P>0.05). The expression of CD56 was different among different immunoglobulin types of MM, and the types of immunoglobulin with an expression from high to low were non-secretory, IgA, IgG, and light chain (P<0.05). Conclusion The 4-color and 10-antibody flow cytometry immunophenotyping panel using 10 antibodies including CD45, CD38, CD19, CD56, CD20, CD5, CD10, HLA-DR, κ antibody and λ antibody marked by four kinds of fluorescein including PE, FITC, PerCP and APC has a good diagnostic value for MM.
