The process of multi-parametric flow cytometry data analysis is complicate and time-consuming, which requires well-trained professionals to operate on. To overcome this limitation, a method for multi-parameter flow cytometry data processing based on kernel principal component analysis (KPCA) was proposed in this paper. The dimensionality of the data was reduced by nonlinear transform. After the new characteristic variables were obtained, automatical clustering can be achieved using improvedK-means algorithm. Experimental data of peripheral blood lymphocyte were processed using the principal component analysis (PCA)-based method and KPCA-based method and then the influence of different feature parameter selections was explored. The results indicate that the KPCA can be successfully applied in the multi-parameter flow cytometry data analysis for efficient and accurate cell clustering, which can improve the efficiency of flow cytometry in clinical diagnosis analysis.
Objective The aim is to sort CD90+ subpopulation cells in human liver cancer cell lines and investigate efficiency of magnetic cell sorting (MACS) on sorting the liver cancer stem cells. Methods ①Expressions of CD90. Immunohistochemical method was used to determine the expressions of CD90 in normal liver tissues in 8 cases, liver cancer and adjacent liver cancer tissues in 58 cases. ②Screened the cell lines. Huh-7, MHCC97-H, Bel-7402, and SMMC-7721 cell lines were divided into blank control group and experimental group (5.5×105 cells per hole, 1 hole), cells of the experimental group were added with 5 μL CD90–PE while cells of the blank control group were treated with 5 μL CD90–PE non fluorescent antibody. Determined the proportion of CD90+ cells in the 2 groups by flow cytometry (FCM). ③MACS. Huh-7 and MHCC97-H cell lines were labeled with magnetic beads respectively and sorted by MACS, 1 mL cell suspensionsorted by magnetic sorting (MS) was collected as CD90– group, and 1 mL PBS after MS wash was collected as CD90+ group, as well as blank control group and experimental group. Determined the proportion of CD90+ cells in 4 groups by FCM. Two times of MACS were performed in Huh-7 cells. ④Serum free culture and serum culture. Huh-7 cells were divided into serum-free culture group and serum culture group (1 hole), and proportions of CD90+ cells were determined by FCM at 1 week after culture. Results ①The positive rate of CD90 was 0 (0/8), 65.5% (38/58), and 20.7% (12/58) in normal liver tissues, liver cancer tissues, and adjacent liver cancer tissues respectively, and the positive rate of CD90 was higher in liver cancer tissues than those of normal liver tissues (χ2=6.78, P<0.05) and adjacent liver cancer tissues (χ2=20.83, P<0.05). ②For Huh-7, MHCC97-H, SMMC-7721, and Bel7402 cell lines, the proportions of CD90+ cells in the experimental group was 0.851%, 1.090%, 2.710%, and 4.050% respectively, the proportions of CD90+ cells in the blank control group was 0.241%, 0.688%, 1.890%, and 2.080% respectively, so we chose Huh-7 and MHCC97-H cell lines to perform MACS. ③Results of MACS for Huh-7 cell line. For the first MACS, the proportions of CD90+ cells in the blank control group, experimental group, CD90– group, and CD90+ group was 0.241%, 0.851%, 0.574%, and 1.100% respectively. For the second MACS, the proportions of CD90+ cells in the blank control group, experimental group, CD90– group, and CD90+ group was 0.032%, 0.961%, 0.426%, and 9.700% respectively. Conclusions The normal liver tissues do not express the CD90, but the liver cancer tissues express CD90 highly. There is a few CD90+ cells in Huh-7 and MHCC97-H liver cancer cell lines. The MACS has a certain effect on improving the proportion of CD90+ cells in the cell lines. The serum-free suspension culture has no effect on enriching CD90+ cells.
Objective To explore the clinical significance of the platelet glycoproteins CD62p and CD63 in septic patients.Methods The expressions of CD62p and CD63 in peripheral platelet were measured in 40 septic patients within 24 hours after onset by flow cytometry.The expression levels of CD62p and CD63 in mild and severe sepsis and normal subjects were compared.Meanwhile the correlation of CD62p and CD63 with APACHE Ⅱ score was analyzed.Results Significant differences in the CD62p and CD63 levels were found in the septic patients when compared with the normal subjects [CD62p：（2.56±1.51）% vs （1.48±0.40）%；CD63：（2.15±0.50）% vs （1.29±0.35）%；all Plt;0.01].The expressions of CD62p and CD63 in the severe septic patients were significantly higher than those in the mild septic patients [CD62p：（3.31±1.94）% vs （2.05±0.87）%；CD63：（2.37±0.36）% vs （2.00±0.53）%；all Plt;0.05].The positive correlations of CD62p and CD63 with APACHE Ⅱ score were also found（CD62p：r=0.377，P=0.016；CD63：r=0.452，P=0.003）.Conclusion Platelets were significantly activated in septic patients at early stage which was correlated with the severity of sepsis.
Purpose To study inhibition effects of retinal pigment epithelial (RPE) cells by hyaluronic acid-stimulating activity(HASA)． Methods The cultured human RPE cells added with a series of HASA was measured with cell counting,tetrazolium(MTT)colorimetric assay and tritium labelled thymidine deoxyribosｅ(3H-TdR)incorporation assay.Flow cytometry(FCM)analysis was used to examine RPE cells cycles. Results HASA at concentrations of 12.5～200 mu;g/ml and within 48 hours inhibited RPE cells proliferation with a dose-dependant and time dependant manners.The maximal inhibition rate of RPE cells by HASF was about 48.0%.FCM revealed that the cells in G1 phase increased 7.2% and cells in S phase decreased 9.7%,compared to controls. Conclusion HASA at a certain dose range and period can inhibit RPE cells proliferation. (Chin J Ocul Fundus Dis,1999,15:72-74)
Objective To investigate the effect of peritoneal exudative cells as feeder cells on growth state of primary culture of adult rat retinal Muuml;ller cells. Methods Peritoneal exudative cells were gained from adult rats, which were identified with specifically biological marker of macrophage (CD68). The phagocytosis was evaluated by the ink particles experiment. Retinal Muuml;ller cells of adult rats were cultured by enzyme digestion method, and identified by GFAP and vimentin immunocytochemically. As the feeder cells, peritoneal exudative cells were cocultured with Muuml;ller cells. The proliferation cycle of Muuml;ller cells was assayed by flow cytometry. One-step TUNEL staining was employed to detect the apoptotic Muuml;ller cells. Results Over ninety-five percent of rat peritoneal exudative cells were macrophage, which have a favourable phagocytic ability for the ink particles. The primary cultured Muuml;ller cells adhered to the wall of flask and grew fast, with large applanate cell bodies. The third-generation cells grew slowly. After cocultured with feeder cells, the Muuml;ller cells showed more rapid growth rate with more cells in S and G2/M phase(S phase, t=4.172, Plt;0.001; G2/M phase, t=3.562, Plt;0.01） and less apoptotic rate (t=3.804, Plt;0.01). The growing cycle was cut down from 25-30 days to 1822 days for the firstgeneration cells, from 10-15 days to 7-10 days for the second-generation cells. Conclusion It is an effective method to use the peritoneal exudative cells as feeder cells cocultured with primary culture of retinal Muuml;ller cells, which can shorten the culture period of Muuml;ller cells in adult rats.
ObjectiveTo explore the effect of the serum high mobility group box-1 (HMGB1) on oncosis of pancreatic acinar cells in the rat with severe acute pancreatitis (SAP). MethodsThirty-two healthy SD rats were randomly divided into 2 groups:sham operation group (SO group, n=8) and SAP group (n=24). Rats of SO group were only flipped the intestinal canal after laparotomy, but rats of SAP group were induced by retrograde injection of 3% sodium taurocholate into bilio-pancreatic duct in addition. Rats of SO group were sacrificed at 6 hours after operation, and rats of SAP group were sacrificed at 6 (SAP-6 hour group, n=8), 12 (SAP-12 hour group, n=8), and 24 hours (SAP-24 hour group, n=8) after operation respectively. Pancreatic tissues were stained by HE to observe pathological changes. Serum HMGB1 was measured by ELISA, and the oncosis percentage of pancreatic acinar cells was examined by flowcytometry. ResultsPathological results showed that structural integrity was observed in pancreatic acinar, and occasionally a single inflammatory cell infiltration was observed in rats of SO group. Swelling, interstitial edema, and inflammatory cell infiltration were observed in rats of SAP-6 hour group. Some necrosis of pancreatic acinar cell, stromal vascular congestion, and focal necrosis were observed in rats of SAP-12 hour group and SAP-24 hour group, which the pathological damage were worse over time. Levels of serum HMGB1 and oncosis percentages of pancreatic acinar cells in rats of 3 SAP subgroups were all higher than those of SO group (P < 0.01), and the 2 kinds of indexes both increased over time (P < 0.05). There was positive correlation between concentration of serum HMGB1 and oncosis percentages of pancreatic acinar cells in SAP rat during 24 hours after operation (r=0.846, P < 0.01). ConclusionsHMGB1 seems to play an important role in SAP by inducing oncosis of pancreatic acinar cells when inducing inflammatory reaction in rat with SAP.
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)
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)
PURPOSE:To evaluate the value of the apoptosis-suppressing oncogene bcl-2 protein expression in the development and progression of uveal and conjunctival melanomas. METHODS:Using flow cytometry and immunofluorescence methods to detect the bcl-2 protein expression in 40 cases of uveal malignant melanomas (UMM), 5 cases of conjunctival nevi (CN) and 7 cases of conjunctival malignant melanomas (CMM). RESULTS :The expression content of bcl-2 protein in CMM was significantly higher than that in CN (P＜0.05);the bcl-2 protein positive expression percentages in CMM and UMM were 85.71% and 72.50% respectively. The expression content of bcl-2 protein in UMM was not related to pathological classfication, scleral invasion,ciliary body involvement,and tumor dimensions (P＞0.05). CONCLUSIONS: The over-expression of bcl-2 protein and apoptosis suppressing might be related to the pathogenesis of CMM and UMM;bcl-2 protein expression might be helpful in discriminating CN from CMM, but unavailable in evaluating the patholgical malignancy of UMM. （Chin J Ocul Fundus Dis,1997,13: 73-74 ）