Apolipoprotein C1 promotes prostate cancer cell proliferation in vitro.

Here, we aimed to investigate the carcinogenic effects of apolipoprotein C1 (APOC1) in prostate cancer (PCa). APOC1 expression was evaluated in PCa and normal prostate specimens, and lentivirus-mediated RNA interference was used to knockdown APOC1 in DU145 cells. The effects of APOC1 silencing on cell proliferation, cell cycle arrest, and apoptosis were assessed. APOC1 expression was much higher in PCa tissues than in normal tissues. Moreover, APOC1 silencing inhibited cell proliferation and colony formation, arrested cell cycle progression, and enhanced apoptosis in DU145 cells. Additionally, APOC1 silencing decreased survivin, phospho-Rb, and p21 levels and increased cleaved caspase-3 expression. These data supported the procarcinogenic effects of APOC1 in the pathogenesis of PCa and suggested that targeting APOC1 may have applications in the treatment of PCa.

Characterization of a water-soluble polysaccharide from Boletus edulis and its antitumor and immunomodulatory activities on renal cancer in mice.

A polysaccharide (BEP, Mw=113,432Da) was purified from Boletus edulis, which had a backbone consisting of (1→6)-linked-α-d-glucopyranosyl, (1→2,6)-linked-α-d-galactopyranosyl, (1→6)-linked-α-d-galactopyranosyl, and (1→3)-linked-α-d-rhamnopyranosyl residues, which were branched at O-2 position of (1→2,6)-linked-α-d-galactopyranosyl residue with a single terminal (1→)-linked-α-l-arabinofuranosyl residue. After 32 days' BEP administration to Renca tumor bearing mice, the tumor mass of Renca transplanted in mice was significantly repressed. Furthermore, BEP could significantly increase the spleen and thymus indices, stimulate splenocytes proliferation, augment NK cell and CTL activities in spleen, and promote the secretion of the cytokines IL-2 and TNF-α in Renca tumor bearing mice. Meanwhile oral administration of BEP (100 and 400mg/kg) restored all the altered hematological and biochemical parameters of tumor-bearing mice to normal levels. Thus, these data demonstrate that BEP possesses potential immunomodulatory activity and might be employed as effective therapeutic agents for the prevention of renal caner.

Prognostic factors for renal allograft survival in patients with immunoglobulin A nephropathy: a case control study.

The renal allograft survival rates of patients with immunoglobulin A nephropathy (IgAN), and patients with or without other glomerular diseases, have yet to be fully elucidated. In this study, the clinicopathological factors associated with long-term allograft survival for the prognosis of renal allograft recipients with IgAN were examined. All patients enrolled in this study were diagnosed with IgAN following clinical and pathological examinations. Patients underwent renal graft biopsy and were hospitalized at the Fuzhou General Hospital between June, 2004 and December, 2010. Common demographic and clinical indicators were recorded in patients who had graft loss and in those who had functional renal grafts. Forty-two of the 202 biopsy specimens (20.8%) met the diagnostic criteria for IgAN and were divided into two groups, the graft loss group (n=17) and the functional graft group (n=25). Patients were followed up for 1-257 months after kidney transplantation. The mean patient age was 40.6 ± 9.3 years at the time of renal graft biopsy. Examination results indicated concomitant proteinuria and hematuria in 25 patients (59.5%) and proteinuria alone in six patients (14.3%). Graft loss occurred in 17 patients during the follow-up period. Comparison of the graft loss and the functional graft groups indicated that patients in the graft loss group were more likely to have proteinuria (P=0.047), high creatinine levels at the time of biopsy (P=0.009), low glomerular filtration rates (P=0.013), low serum total protein (P=0.01), a high Banff score (P=0.001), extensive glomerulosclerosis (P=0.002), a greater likelihood of crescent formation (P=0.01), severe tubular atrophy (P=0.013) and more extensive interstitial fibrosis (P=0.033). However, the two groups showed no significant differences in blood pressure, hematuria, BUN, UA, Hb, TG and CHO levels. The allograft survival rate of patients with IgAN was identified to be similar to that of patients with and without other glomerular diseases.

Suppression of SCIN inhibits human prostate cancer cell proliferation and induces G0/G1 phase arrest.

SCIN is a calcium regulated actin severing and capping protein. Its homologue in zebrafish is found to be related with cell death. In the present study, we found that SCIN is highly expressed in human prostate cancer specimens. However, the functions of SCIN in human prostate carcinoma cells are largely unknown. To address the function of SCIN in prostate carcinoma cells, we used lentivirus-mediated RNAi to knock down SCIN expression in PC3 cells, a prostate carcinoma cell line. We found that in vitro silencing of SCIN could inhibit the proliferation and colony formation ability of PC3 cells. Furthermore, cell cycle analysis showed that reduced SCIN expression lead to G0/G1 cell cycle arrest through the regulation of cell cycle-related genes, such as p21Waf1/Cip1, cyclin-dependent kinase inhibitor 2A (CDKN2A, p16Ink4A) and cyclin A2. These results suggest that SCIN plays an important role in the proliferation of prostate cancer cells and lentivirus-mediated inhibition of SCIN expression may be a potential therapeutic method for the treatment of prostate cancer.

BMSCs reduce rat granulosa cell apoptosis induced by cisplatin and perimenopause.

BACKGROUND: The objective of this study was to evaluate the effect of bone marrow mesenchymal stem cells (BMSCs) on the apoptosis of granulosa cells (GCs) in rats. RESULTS: Cisplatin increased GC apoptosis from 0.59% to 13.04% in the control and cisplatin treatment groups, respectively, which was significantly reduced upon co-culture with BMSCs to 4.84%. Cisplatin treatment increased p21 and bax and decreased c-myc mRNA expression, which was reversed upon co-culture with BMSCs. As compared to young rats, increased apoptosis was observed in the perimenopausal rats (P < 0.001). After 3 months, the apoptosis rate in the BMSC group was significantly lower than that of the control group (P = 0.007). CONCLUSIONS: BMSC therapy may protect against GC apoptosis induced by cisplatin and perimenopause. Further studies are necessary to evaluate therapeutic efficacy of BMSCs.

[Use of limited sampling strategy for estimating area under concentration-versus-time curve of mycophenolate sodium in renal allograft recipients].

OBJECTIVE: To establish a formula for estimating area under the concentration-versus-time curve (AUC) of mycophenolate sodium in Chinese renal allograft recipients with a limited sampling model. METHODS: A total of 35 renal allograft recipients were recruited from 2010 to 2013 to receive enteric-coated mycophenolate sodium (EC-MPS), calcineurin (CNI) and prednisone as immunosuppressive triple therapy. The serum concentration of mycophenolic acid (MPA) was assayed by enzyme multiplied immunoassay technique (EMIT) at pre-dose (C0), 0.5 (C0.5), 1.0 (C1), 1.5 (C1.5), 2.0 (C2), 3.0 (C3), 4.0 (C4), 6.0 (C6), 8.0 (C8) and 12.0 (C12) h post-dose respectively. Pharmacokinetic parameters of MPA (C0, C12, Cmax, Tmax, AUC0-12 h) were calculated by software WINNOLIN. Simplified formulae for estimation of MPA-AUC in tacrolimus (Tac) group or cyclosporin A (CsA) group were established by multiple stepwise regression analysis. RESULTS: There were variable MPA AUC0-12 h levels between 14 and 67 mg×h/L (mean: 37 ± 14). The MPA trough level (C0) had no correlations with MPA AUC0-12 h (r(2) = 0.090) . The simplified MPA AUC formula for Tac group was AUC = 5.678+1.718×C4+2.853×C6+1.812×C8+3.413×C12 with four sampling points (C4, C6, C8, C12). Estimated AUC with the formula had correlations with AUC0-12 h (r(2) = 0.890). The mean absolute predict error (APE) was 3.45% (0.41%-24.71%) and the proportion of APE above 15% stood at 11.1% (2/18) . In CsA group, the simplified MPA AUC formula was AUC = 7.072+1.525×C3+1.558×C4+ 1.573×C6+2.285×C8. The correlation was r(2) = 0.952, mean APE was 6.50% (0.02%-12.91%) and proportion of APE above 15% stood at 0. The above formulae were observed to have agreement with AUC0-12 h by Bland-Altman analysis. CONCLUSION: The simplified MPA AUC formulae with 4-point sampling provide an effective approach for estimating full MPA AUC0-12 h in Chinese renal recipients on EC-MPS plus tacrolimus or cyclosporin A.

[Effect of CYP3A4*18B, CYP3A5*3 gene polymorphism on dosage and concentration of tacrolimus in renal transplant patients].

The effect of CYP3A4*18B and CYP3A5*3 on concentration/dosage x body surface area ratios (C/D'), adverse effects and acute rejection of tacrolimus in renal transplant patients were investigated. The CYP3A4*18B genotypes of 227 renal transplant patients were determined by PCR-RFLP method. The differences of C/D' ratios, adverse reactions and acute rejection were compared among all of the genotype groups treated with tacrolimus. The frequencies of CYP3A4*18 and CYP3A5*3 alleles in renal transplant patients were 30.8% and 74.2%, respectively. No significant association was found between the C/D's of tacrolimus and CYP3A4*18B genotypes when they were classified by two CYP3A5 genotypes (P > 0.05). While after the effects of CYP3A4*18B genotype were eliminated, the C/D' ratio of tacrolimus in patients with CYP3A5*1/*1 and *1/*3 genotype group was significantly lower than those with CYP3A5*3/*3 genotype groups (P < 0.01). There is no significant difference in adverse effects and acute rejection among different genotypes (P > 0.05).

Alemtuzumab induction therapy in highly sensitized kidney transplant recipients.

BACKGROUND: Immunosuppression for immunologically high-risk kidney transplant patients usually involves antithymocyte globulin induction with triple drug maintenance therapy. Alemtuzumab, a humanized anti-CD52 antibody, was expected to be a promising induction therapy agent for kidney transplantation. However, currently no consensus is available about its efficacy and safety. This study aimed to evaluate the efficacy and safety of alemtuzumab as immune induction therapy in highly sensitized kidney transplant recipients. METHODS: In this prospective, open-label, randomized, controlled trial, we enrolled 23 highly immunological risk patients (panel reactive antibody > 20%). They were divided into two groups: alemtuzumab group (trial group) and anti-thymocyte globulin (ATG) group (control group). Patients in the alemtuzumab group received intravenous alemtuzumab (15 mg) as a single dose before reperfusion. At the 24th hour post-operation, another dosage of alemtuzumab (15 mg) was given. The control group received a bolus of rabbit ATG (9 mg/kg), which was given 2 hours before kidney transplantation and lasted until the removal of vascular clamps when the anastomoses were completed. Maintenance immunosuppression in both groups comprised standard triple therapy consisting of tacrolimus, prednisone, and mycophenolate mofetil (MMF). Acute rejection (AR) and infection episodes were recorded, and kidney function was monitored during a 2-year follow-up. χ(2) test, t test and Kaplan-Meier analysis were performed with SPSS17.0 software. RESULTS: Median follow-up was 338 days. In both the alemtuzumab group and ATG group, creatinine and blood urea nitrogen values in surviving recipients were similar (P > 0.05). White blood cell counts were significantly reduced in the alemtuzumab group for the most time points up to 6 months (P < 0.05). One patient receiving alemtuzumab died for acute myocardial infarction at the 65th day post-operation. Two ATG patients died for severe pulmonary infection or cardiac and pulmonary failure. Cumulative 2-year graft survival rate was 90.9% in the alemtuzumab group and 81.8% in ATG group (P > 0.05) respectively. There was one graft failure in the alemtuzumab group and two graft failures in ATG group, with all graft failures at tributed to rejection episodes. The alemtuzumab group had a 2-year cumulative freedom from rejection rate of 81.8%, compared with 72.7% for the ATG group (P > 0.05). CONCLUSION: Alemtuzumab induction therapy for highly sensitized kidney transplant recipients is an effective and safe protocol yielding an acceptable acute rejection rate.

[Effects of delta1 gene transfection on biological behaviors of rat dendritic cells].

AIM: To explore the effects of Delta1 gene on rat bone marrow-derived dendritic cells (DCs). METHODS: pcDNA3.1/delta1 plasmid was transfected into Rat DCs with lipofectamine gene transfection method. The expression of activation markers(Iad, CD80 and CD86) were examined by flow cytometry, the release of cytokines IL-12 were examined by ELISA and the stimulatory capacity of the resulting DCs in vitro were examined by mixed lymphocyte reaction(MLR). RESULTS: The biological character of DCs in experimental group, empty vector group and control group were examined by electron microscope, flow cytometry and cell growth rate counting. There were no differences of cell cycles, ultrastructure and cell growth rate among these three group cells (P>0.05). It stated that delta1 gene had no effect on the growth of DCs. Even at the stimulation of LPS, In the delta1 transfected DCs, we observed no significant effects on the expression of activation markers(Iad, CD80 or CD86). The release of IL-12 in DCs/delta1 was reduced compared with control DCs(P<0.05). The levels of IFN-gamma and IL-2 of the DCs/delta1 were significantly lower than those of the DCs(P<0.05), and the levels of IL-4 and IL-10 were significantly higher than that in control DCs(P<0.05). CONCLUSION: Our data demonstrates that the delta1 gene transfection does not interfere with the differentiation or maturation of DCs, but reduce the ability to stimulating T cells, and the mechanism may be related to the decrease of Th1 /Th2 ratio by impairing the production of DCs-derived IL-12.

Pre-transplant soluble CD30 level as a predictor of not only acute rejection and graft loss but pneumonia in renal transplant recipients.

Pre-transplant sera of 586 renal graft recipients were tested to investigate whether soluble CD30 (sCD30) is a useful predictor of some severe clinical episodes post-transplant. Correlation analysis showed sCD30 level was significantly correlated with acute rejection (AR) (r=0.242, P<0.001), graft loss (r=0.162, P<0.001), and pneumonia (r=-0.147, P<0.001). Higher sCD30 levels were observed in patients with AR than the others (180.0+/-89.1 vs. 135.3+/-72.7U/ml, P<0.001). And patients with pneumonia had significantly lower pre-transplant sCD30 level than the others (123.2+/-75.5 vs. 150.7+/-79.6U/ml, P=0.003). Based on statistical results, 120 and 240U/ml were selected as the optimal couple of cut-off value to divide patients into three groups: Group High (H), Group Intermedial (I) and Group Low (L). The lowest AR rate of 17.4% was observed in Group L (P<0.001). Significant difference of AR rate was also observed between Group I (29.2%) and H (42.9%) (P<0.001). There were much more patients suffering pneumonia in Group L (P=0.001). Significantly lower 5-year patient survival rate (79.4%) was observed in Group H (P=0.016). These data showed that elevated pre-transplant sCD30 level of renal allograft recipients may reflect an immune state detrimental for renal allograft survival. But sCD30 level lower than <120U/ml may be associated with a high risk of pneumonia. Pre-transplant sCD30 level is an independent predictor of acute rejection, lung infection, even graft survival. Suitable immunosuppression protocol should be selected according to pre-transplant sCD30 level in an attempt to promote patient and graft survival.

Factors influencing second renal allograft survival: a single center experience in China.

Second renal transplants are historically associated with a poor prognosis. The aim of the present study was to assess long-term survival of second renal grafts from deceased donors performed at our center and to analyze risk factors associated with long-term graft outcome. Sixty-five second renal grafts were enrolled into this study, and compared to primary ones performed during the same period. Kaplan-Meier curve showed a graft survival rate of 89.2% at 1 year, 80% at 3 years, and 63.1% at 5 years, which were similar to that of primary graft. Univariate analysis showed that time to first graft loss, cold ischaemia time, HLA mismatch, primary maintenance immunosuppressant, acute rejection episodes, and serum creatinine at 1 year were significantly associated with regraft survival. Cox regression demonstrated the dominant effect of acute rejection episodes, primary maintenance immunosuppressant, serum creatinine at 1 year, and time to first graft loss as predictor of second graft outcome. However, when long-term survival of second graft was examined on the basis of Kaplan-Meier estimates, HLA mismatch was found to be significant. The second graft had more benefits of improved pre-transplant screening and post-transplant management, and its survival rate was satisfactory and similar to that of primary one. Immunologic factors such as acute rejection and primary immunosuppressant are the main determinants of long-term renal transplantation outcome.

The long-term outcomes of pediatric kidney transplantation: a single-centre experience in China.

To explore the long-term outcomes of paediatric kidney transplantation and the effects of renal allograft on growth, education, employment, marriage and procreation. Twenty-seven children with ESRD received the renal allograft from 1985 to 2001. The patient and kidney survival rate, renal function, growth and employment, etc., were reviewed retrospectively. The average follow-up period was 10.3 +/- 4.4 yr. The one-, three-, five- and 10-yr graft survival rates were 96.3%, 88.9%, 81.5% and 66.7%, respectively, and the corresponding patient survival rates were 100%, 92.6%, 85.2% and 68.8%. The body weight gain was 4-10 kg in one-yr post-operative and the height increased 0-2 cm for girls and 2-5 cm for boys. A total of 44.4% of the recipients accomplished their education above junior high school. The employment rate was 46.2% in males, and 57.2% in females. Twelve patients were married. Non-adherence occurred in 30% of the recipients. Forty percent of the surviving recipients developed complications. Seven patients died. More attention should be paid to non-adherence of medications and more supports from the society are required to improve the life quality of paediatric recipients, especially in employment and education.

Comparison of single bolus ATG and Basiliximab as induction therapy in presensitized renal allograft recipients receiving tacrolimus-based immunosuppressive regimen.

Presensitized renal allograft recipients require special management to improve their outcome, and there is no consensus on the optimal immunosuppressive strategy. We retrospectively analyzed clinical data of 82 patients, who were PRA positive pre-transplant (above 10%) and received single bolus ATG and basiliximab as induction therapy, and assessed safety and efficacy of two kinds of induction therapies. Patients of ATG group (n=40) received single bolus ATG (Fresenius, 9 mg/kg preoperatively) and those of basiliximab group (n=42) were given two doses of basiliximab (Simulect, Novartis, 20 mg) on days 0 and 4 post-transplant. All patients received standard triple immunosuppressive therapy with tacrolimus (FK-506), mycophenolate mofetil (MMF), and steroids. The follow-up time was 12 months. There was no hyperacute rejection in two groups, and delayed graft function occurred in two patients of ATG group and three of basiliximab group. After 12-month follow-up, more acute rejection (AR) episodes were observed in basiliximab group than ATG group (35.7% vs. 15%, P=0.032). Although highly significant differences were observed between ATG group and basiliximab group with respect to the incidence of thrombocytopenia (P=0.001), single bolus ATG was well tolerated. Incidences of other adverse events and infection episodes did not differ between two groups (P>0.05). One-year patient and graft survival was 95%, 92.5% and 95.2%, 88.1% in ATG and basiliximab group respectively (P>0.05). Both single bolus ATG and basiliximab induction therapy achieved similar one-year graft/patient survival. However, single bolus ATG yielded much lower AR rate than basiliximab without increase in infection episodes and severe adverse events.

Pre- and post-transplant monitoring of soluble CD30 levels as predictor of acute renal allograft rejection.

Identification of renal graft candidates at high risk of impending acute rejection (AR) and graft loss may be helpful for patient-tailored immunosuppressive regimens and renal graft survival. To investigate the feasibility with soluble CD30 (sCD30) as predictor of AR, sCD30 levels of 70 patients were detected on day 0 pre-transplant and day 1, 3, 5, 7, 10, 14, 21, and 30 post-transplant. AR episodes in 6 months were recorded and then patients were divided into Group AR (n=11) and Group UC (n=59). Results showed that the patients had higher pre-transplant sCD30 levels than healthy people. A significant decrease of sCD30 was observed on the first day post-transplant and continued until day 14 post-transplant. Soluble CD30 presented a stable level from day 14 to 30 post-transplant. Pre-transplant sCD30 levels of Group AR were much higher than those of Group UC (P<0.001). Patients of Group AR also had higher sCD30 levels than those of Group UC on day 1, 3, 5, 7, 10 and 14 (P<0.001). The sCD30 level presented a significantly delayed decrease in the patients of Group AR. Statistical results showed that the highest value of area under ROC curve (0.95) was obtained on day 5 post-transplant, suggesting that sCD30 levels on day 5 are of high predictive value. Therefore, sCD30 level may be a good marker of increased alloreactivity and of significant predictive value. It's necessary to monitor the variation of sCD30 in the early period post-transplant.

[Comparison of biologic activity of two anti-PSA/anti-CD3 bispecific single-chain antibodies].

OBJECTIVE: To study and compare the biologic activity of two anti-PSA/anti-CD3 bispecific single-chain antibodies. METHODS: Flow cytometry (FCM) was used to detect the binding activity of two antibodies to CD3-positive cell line Jurkat and prostate carcinoma cell line LNCaP. The effect of the two antibodies in mediating tumor cell lysis in vitro was determined by using the 51Cr-release test. For in vivo evaluation of the two antibodies activity, a nude mouse model was used. The mice were inoculated with LNCaP prostate cancer cells. RESULTS: FCM showed that both the antibodies could bind Jurkat and LNCaP cells with high specificity. The percentages of the cells bond by the bispecific single-chain antibodies were 56.3% and 55.4%, and those by the multivalent antibodies were 74.0% and 83.0% respectively. Both the antibodies mediated a specific lysis of LNCaP cells in vitro, with activated CTLs as effector cells, and significantly reduced tumor growth of nude mice in vivo as compared with the untreated controls and the group treated with CTLs only (P <0.05). The experiment also showed that the multivalent antibody had a better activity than the bispecific antibody in binding antigens, mediating lysis of LNCaP cells and reducing tumor growth (P < 0.05). CONCLUSION: Both the anti-PSA/anti-CD3 bispecific single-chain antibody and multivalent antibody have good biologic activity, and the formation of the tetramerization of single-chain antibody can improve its biologic activity.

Preoperative single-bolus high-dose antithymocyte globulin as induction therapy in sensitized renal transplant recipients.

BACKGROUND: Immunological sensitization remains a major problem following renal transplantation. There is no consensus for the management of sensitized renal allograft recipients. The patients become tethered to dialysis while waiting for compatible donors. This study was designed to evaluate the efficacy and safety of preoperative single-bolus high-dose antithymocyte globulin (ATG) as induction therapy in sensitized renal transplant recipients. METHODS: A total of 56 patients were divided into two groups according to the level of panel reactive antibody (PRA): non-sensitized group (PRA < 10%, n = 30) and sensitized group (PRA > or = 10%, n = 26). The characteristics of the recipients and donors were comparable between the two groups. Mycophenolate mofetil (MMF, 1 g) or ATG (iv. 9 mg/kg) were given preoperatively in the two groups as induction therapy. After the transplantation, the patients were treated with standard triple therapy regimen consisting of tacrolimus (FK-506) or cyclosporine A, MMF, and prednisolone. Acute rejection (AR) and infection episodes were recorded and renal function was monitored during a 12-month follow-up. Chi(2) test and t test were used to analyze the data. RESULTS: During the follow-up, 6 patients (20.0%) suffered AR episodes in the non-sensitized group and 4 (15.4%) in the sensitized group (P = 0.737); 8 patients (26.7%) experienced 11 infection episodes (average, 1.4 episodes per infected patient) in the non-sensitized group, and 6 (23.1%) experienced 10 infection episodes (average, 1.7 episodes per infected patient) in the sensitized group (P = 0.757, 0.890). The safety of the drugs, which was assessed by the occurrence of side effects, was comparable between the two groups. The hospital stay was 13 - 25 days (mean, 16.7 +/- 3.3) in the non-sensitized group and 14 - 29 days (mean, 16.2 +/- 3.1) in the sensitized group, respectively (P = 0.563). No delayed graft function (DGF) was observed in all the patients. Both the 12-month actuarial patient and graft survival rates were 100% in the two groups. CONCLUSION: Preoperative single-bolus high-dose ATG is an effective and safe induction therapy yielding acceptable acute rejection rate in sensitized renal transplant recipients.

[Biologic activity of bispecific single chain antibody against human gamma-seminoprotein and CD3 molecule].

AIM: To construct a recombinant vector which expresses bispecific single chain antibody (BsscFv) against human gamma-seminoprotein and CD3 molecule and evaluate its biologic activity. METHODS: The BsscFv gene was constructed by the splicing overlap extensive (SOE) PCR and then a flexible peptide linker was inserted between anti-human gamma-seminoprotein single chain Fv gene and anti-CD3 single chain Fv gene. The fusion gene was subcloned into the pSectag2-B plasmid and was expressed in HeLa cell lines. After being analyzed by SDS-PAGE and Western blot, the expressed product was purified through a Ni(2+)-NTA superflow affinity chromatography column. Flow cytometry (FCM) was used to detect the binding activity of BsscFv to CD3(+) cell line Jurkat cells and prostate carcinoma cells LNCaP. In vitro killing effect on target cells (LNCaP) mediated by BsscFv was determined by chromium(51)-release test. The effect of CTLs mediated by BsscFv on inhibiting tumor growth was observed by utilizing nude mice bearing prostate cancer cells. RESULTS: DNA sequencing indicated that BsscFv gene consisted of 1,500 bp, encoding 500 amino acids. SDS-PAGE and Western blot analysis showed that the expressed product with relative molecular mass of 61,000 existed in culture supernatant of Hela cells. Flow cytometry analysis demonstrated that the binding rate of BsscFv to LNCaP cells and Jurkat cells was 54.1% and 53.7%, respectively. In vitro, BsscFv mediated cytotoxicity of CTLs to LNCaP cells as confirmed by chromium(51)-release assay. In prostate cancer nude mouse model, BsscFv inhibited tumor's growth as compared with control group. CONCLUSION: The BsscFv against human gamma-seminoprotein and CD3 molecule possesses certain biologic activity, and in vitro and in vivo it can mediate cytotoxicity of CTLs to prostate cancer cells.

[Prolongation of survival time of allogenous skin graft after transfection of Molluscum contagiosum virus 148 gene in rats].

OBJECTIVE: To explore the immunosuppressive effect of local transfection of Molluscum contagiosum virus 148 (MC148) gene to allogenous skin graft against rejection. METHODS: MC148 gene was cloned from molluscum contagiosum virus (MCV), and was employed to construct recombinant adenovirus vector (Ad-MC148). The recombinant Ad-MC148 was then locally transfected into a part of the tail skin of eight Lewis rats, which served as skin donors for grafting. The wounds (1 cm x 1 cm) were produced on the tails of 16 Wistar rats, and they were then randomly divided into control (C, n=8, with grafting of skin from donor rats without transfection), and transfection (T, n=8, with grafting of skin from donor rats with transfection of the recombinant Ad-MC148) groups. The expression of MC148 mRNA gene in T group was detected on 6 post operation hour( POH) and 2, 3, 7 and 10 post operation day (POD), and the results were expressed by the ratio of absorption value (A) between MC148 gene and beta-actin. The survival time of skin grafts in both groups was compared. Gross examination of grafted skin was carried out from 7 POD on in both groups, and the pathomorphological changes were examined in both groups on 7 POD. RESULTS: The MC148 gene expression in rat skin of T group could be identified in 6 POH, and it reached the peak on 3 POD (A(MC148 mRNA) / A(beta_actin) = 0.86), and then subsided thereafter, but it maintained for 10 days. The survival time of the grafts in T group was (15.0 +/- 2.0) days, and it was significantly longer than that in C group (8.5 +/- 3.4) days, (P < 0.01). Gross and microscopic examination showed that the tail skin of T group appeared ruddy on 7 POD, with little leukocytic infiltration in subcutaneous tissue; it began to turn black after 12 to 20 PODs. On the other hand, the tail skin of C group began to turn black and to shed off on 7 POD, with evident leukocytic infiltration in subcutaneous tissue and dermis. CONCLUSION: Local transfection of MC148 gene may promote immunosuppression by inhibiting leukocytic infiltration after allogenous skin transplantation.

[Construction and expression of anti-CD3/anti-prostate-cancer bispecific single-chain antibody].

OBJECTIVE: To construct a recombinant vector that expresses anti-CD 3/anti-prostate-cancer bispecific single-chain antibody (BsAb), and study its biological activities and clinical significance. METHODS: An anti-CD 3/anti-prostate-cancer BsAb was constructed by PCR and molecular biological technique of DNA cloning. The fusion gene, confirmed by sequencing, was subcloned into the pSectag2-B plasmid from the pUC18 vector by digestion with EcoR I and Hind III restriction endonucleases, whose sites exist in both the vectors. Then the recombinant plasmid was transfected into HeLa cells. The expression products in the supernatant were analyzed by both SDS-PAGE and Western blot technique, then were purified with Ni(2+)-NTA superflow affinity chromatography. Its biological activities were examined by flow cytometry (FCM). RESULTS: A fragment of 1.5 kb was inserted into the pUC18 vector, which was sequenced and verified to be identical with that designed. The expression of anti-CD 3 x anti-prostate-cancer BsAb yielded a soluble protein with an apparent molecular mass of 61 KD. The purification rate of the expressed BsAb was up to 90.537% and the yield of purified BsAb from this procedure was 0.09 mg/ml. The positive binding rates of BsAb to PBMC and to PC-3 cell were 54.1% and 53.7% respectively. CONCLUSION: The anti-CD 3 x anti-prostate-cancer BsAb thus constructed exhibits beneficial biological activities and may play an important role in the treatment of prostate cancer.