[Efficacy analysis of surgical combined with postoperative adjuvant therapy for T3 gallbladder carcinoma: a multicenter retrospective study]

Objective: To explore the clinical value of adjuvant therapy in patients with T3 gallbladder cancer (GBC) who have undergone R0 resection. Methods: Clinical and pathological data from 415 patients with T3 GBC who underwent surgical treatment in 7 tertiary centers in China from January 2013 to December 2018 were collected,including 251 males and 164 females,aged (61±11)years (range: 26 to 88 years). Depending on whether to receive adjuvant therapy after radical resection,the patients were divided into the radical resection group alone (group A,n=358) and the radical resection combined with the postoperative adjuvant therapy group (group B,n=57). The general data of the two groups were matched 1∶1 by propensity score matching method,and the caliper value was 0.02.Clinicopathological characteristics,overall survival and disease-free survival of the two groups were compared.The Cox regression model was used for multivariate analysis,and patients with at least one or more independent risk factors were classified as high-risk clinicopathological subtypes. Subgroup analysis was performed to assess the clinical value of adjuvant therapy after radical resection in patients with high-risk clinicopathological subtypes. Results: After the matching,there were 42 patients in each of the two groups. The incidence of gallbladder cancer and the number of dissected lymph nodes in group B after cholecystectomy were higher than those in group A (χ2=9.224,2.570,both P<0.05). There were no significant differences in overall survival rate and disease-free survival rate between the two groups before and after matching (all P>0.05). The results of the univariate and multivariate analysis showed that CA19-9>39 U/ml,nerve invasion,tumor location (liver side or bilateral),TNM stage ⅢB to ⅣB ,poorly differentiated tumor were independent prognostic factors of overall survival and disease-free survival of patients with T3 stage gallbladder cancer (all P<0.05).Three hundred and twenty-nine patients(79.3%) had high-risk clinicopathological subtypes,and the median survival time after curative resection with and without adjuvant therapy was 17 months and 34 months respectively,and the 3-year and 5-year overall survival rates were respectively 40.0%,21.3% and 46.0%,46.0% (χ2=4.042,P=0.044);the median disease-free survival time was 9 months and 13 months,and the 3-year and 5-year disease-free survival rates were 23.4%,13.6% and 30.2%,18.2% (χ2=0.992,P=0.319). Conclusions: Postoperative adjuvant therapy following radical surgery did not yield significant improvements in the overall survival and disease-free survival rates of patients diagnosed with T3 gallbladder cancer. However, it demonstrated a significant extension in the overall survival rate for patients presenting high-risk clinicopathological subtypes.

[Survival analysis of patients with intrahepatic cholangiocarcinoma treated with adjuvant chemotherapy after radical resection based on CoxPH model and deep learning algorithm]

Objective: To establish a predictive model for survival benefit of patients with intrahepatic cholangiocarcinoma (ICC) who received adjuvant chemotherapy after radical resection. Methods: The clinical and pathological data of 249 patients with ICC who underwent radical resection and adjuvant chemotherapy at 8 hospitals in China from January 2010 to December 2018 were retrospectively collected. There were 121 males and 128 females,with 88 cases>60 years old and 161 cases≤60 years old. Feature selection was performed by univariate and multivariate Cox regression analysis. Overall survival time and survival status were used as outcome indicators,then target clinical features were selected. Patients were stratified into high-risk group and low-risk group,survival differences between the two groups were analyzed. Using the selected clinical features, the traditional CoxPH model and deep learning DeepSurv survival prediction model were constructed, and the performance of the models were evaluated according to concordance index(C-index). Results: Portal vein invasion, carcinoembryonic antigen>5 μg/L,abnormal lymphocyte count, low grade tumor pathological differentiation and positive lymph nodes>0 were independent adverse prognostic factors for overall survival in 249 patients with adjuvant chemotherapy after radical resection (all P<0.05). The survival benefit of adjuvant chemotherapy in the high-risk group was significantly lower than that in the low-risk group (P<0.05). Using the above five features, the traditional CoxPH model and the deep learning DeepSurv survival prediction model were constructed. The C-index values of the training set were 0.687 and 0.770, and the C-index values of the test set were 0.606 and 0.763,respectively. Conclusion: Compared with the traditional Cox model, the DeepSurv model can more accurately predict the survival probability of patients with ICC undergoing adjuvant chemotherapy at a certain time point, and more accurately judge the survival benefit of adjuvant chemotherapy.

[A nomogram for preoperative prediction of lymph node metastasis in patients with intrahepatic cholangiocarcinoma based on inflammation-related markers]

Objectives: To construct a nomogram for prediction of intrahepatic cholangiocarcinoma (ICC) lymph node metastasis based on inflammation-related markers,and to conduct its clinical verification. Methods: Clinical and pathological data of 858 ICC patients who underwent radical resection were retrospectively collected at 10 domestic tertiary hospitals in China from January 2010 to December 2018. Among the 508 patients who underwent lymph node dissection,207 cases had complete variable clinical data for constructing the nomogram,including 84 males,123 females,109 patients≥60 years old,98 patients<60 years old and 69 patients were pathologically diagnosed with positive lymph nodes after surgery. Receiver operating characteristic curve was drawn to calculate the accuracy of preoperative imaging examinations to determine lymph node status,and the difference in overall survival time was compared by Log-rank test. Partial regression squares and statistically significant preoperative variables were screened by backward stepwise regression analysis. R software was applied to construct a nomogram,clinical decision curve and clinical influence curve,and Bootstrap method was used for internal verification. Moreover,retrospectively collecting clinical information of 107 ICC patients with intraoperative lymph node dissection admitted to 9 tertiary hospitals in China from January 2019 to June 2021 was for external verification to verify the accuracy of the nomogram. 80 patients with complete clinical data but without lymph node dissection were divided into lymph node metastasis high-risk group and low-risk group according to the score of the nomogram among the 858 patients. Log-rank test was used to compare the overall survival of patients with or without lymph node metastasis diagnosed by pathology. Results: The area under the curve of preoperative imaging examinations for lymph node status assessment of 440 patients was 0.615,with a false negative rate of 62.8% (113/180) and a false positive rate of 14.2% (37/260). The median survival time of 207 patients used to construct a nomogram with positive or negative postoperative pathological lymph node metastases was 18.5 months and 27.1 months,respectively (P<0.05). Five variables related to lymph node metastasis were screened out by backward stepwise regression analysis,which were combined calculi,neutrophil/lymphocyte ratio,albumin,liver capsule invasion and systemic immune inflammation index,according to which a nomogram was constructed with concordance index(C-index) of 0.737 (95%CI: 0.667 to 0.806). The C-index of external verification was 0.674 (95%CI:0.569 to 0.779). The calibration prediction curve was in good agreement with the reference curve. The results of the clinical decision curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set to about 0.32,the maximum net benefit could be obtained by 0.11,and the cost/benefit ratio was 1∶2. The results of clinical influence curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set to about 0.6,the probability of correctly predicting lymph node metastasis could reach more than 90%. There was no significant difference in overall survival time between patients with high/low risk of lymph node metastasis assessed by the nomogram and those with pathologically confirmed lymph node metastasis or without lymph node metastasis (Log-rank test:P=0.082 and 0.510,respectively). Conclusion: The prediction accuracy of preoperative nomogram for ICC lymph node metastasis based on inflammation-related markers is satisfactory,which can be used as a supplementary method for preoperative diagnosis of lymph node metastasis and is helpful for clinicians to make personalized decision of lymph node dissection for patients with ICC.

[Impact of adjuvant chemotherapy on prognosis in intrahepatic cholangiocarcinoma patients underwent radical resection]

Objectives: To investigate the clinical value of adjuvant chemotherapy(ACT) in patients with intrahepatic cholangiocarcinoma(ICC) who underwent radical resection and to explore the optimal population that can benefit from ACT. Methods: A retrospective cohort study method was adopted. The clinical and pathological data of 685 patients with ICC who underwent curative intent resection in 10 Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected;There were 355 males and 330 females. The age(M(IQR)) was 58(14) years (range: 22 to 83 years). Propensity score matching(PSM) was applied to balance the differences between the adjuvant and non-adjuvant chemotherapy groups. Log-rank test was used to compare the prognosis of the two groups of patients. A Bayesian network recurrence-free survival(RFS) prediction model was constructed using the median RFS time (14 months) as the target variable, and the importance of the relevant prognostic factors was ranked according to the multistate Birnbaum importance calculation. A survival prognostic prediction table was established to analyze the population benefiting from adjuvant chemotherapy. Results: Among 685 patients,214 received ACT and 471 did not receive ACT. A total of 124 pairs of patients were included after PSM, and patients in the ACT group had better overall survival (OS) and RFS than those in the non-ACT group(OS: 32.2 months vs. 18.0 months,P=0.003;RFS:18.0 months vs. 10.0 months,P=0.001). The area under the curve of the Bayesian network RFS prediction model was 0.7124. The results of the prognostic factors in order of importance were microvascular invasion (0.158 2),perineural invasion (0.158 2),N stage (0.155 8),T stage (0.120 9), hepatic envelope invasion (0.090 3),adjuvant chemotherapy (0.072 1), tumor location (0.057 5), age (0.042 3), pathological differentiation (0.034 0), sex (0.029 3), alpha-fetoprotein (0.028 9) and preoperative jaundice (0.008 5). A survival prediction table based on the variables with importance greater than 0.1 (microvascular invasion,perineural invasion,N stage,T staging) and ACT showed that all patients benefited from ACT (increase in the probability of RFS≥14 months from 2.21% to 7.68%), with a more significant increase in the probability of RFS≥14 months after ACT in early-stage patients. Conclusion: ACT after radical resection in patients with ICC significantly prolongs the OS and RFS of patients, and the benefit of ACT is greater in early patients.

[A prognostic model of intrahepatic cholangiocarcinoma after curative intent resection based on Bayesian network]

Objective: To examine a survival prognostic model applicable for patients with intrahepatic cholangiocarcinoma (ICC) based on Bayesian network. Methods: The clinical and pathological data of ICC patients who underwent curative intent resection in ten Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected.A total of 516 patients were included in the study.There were 266 males and 250 females.The median age(M(QR)) was 58(14) years.One hundred and sixteen cases (22.5%) with intrahepatic bile duct stones,and 143 cases (27.7%) with chronic viral hepatitis.The Kaplan-Meier method was used for survival analysis.The univariate and multivariate analysis were implemented respectively using the Log-rank test and Cox proportional hazard model.One-year survival prediction models based on tree augmented naive Bayesian (TAN) and naïve Bayesian algorithm were established by Bayesialab software according to different variables,a nomogram model was also developed based on the independent predictors.The receiver operating characteristic curve and the area under curve (AUC) were used to evaluate the prediction effect of the models. Results: The overall median survival time was 25.0 months,and the 1-,3-and 5-year cumulative survival rates was 76.6%,37.9%,and 21.0%,respectively.Univariate analysis showed that gender,preoperative jaundice,pathological differentiation,vascular invasion,microvascular invasion,liver capsule invasion,T staging,N staging,margin,intrahepatic bile duct stones,carcinoembryonic antigen,and CA19-9 affected the prognosis(χ2=5.858-54.974, all P<0.05).The Cox multivariate model showed that gender,pathological differentiation,liver capsule invasion,T stage,N stage,intrahepatic bile duct stones,and CA19-9 were the independent predictive factors(all P<0.05). The AUC of the TAN model based on all 19 clinicopathological factors was 74.5%,and the AUC of the TAN model based on the 12 prognostic factors derived from univariate analysis was 74.0%,the AUC of the naïve Bayesian model based on 7 independent prognostic risk factors was 79.5%,the AUC and C-index of the nomogram survival prediction model based on 7 independent prognostic risk factors were 78.8% and 0.73,respectively. Conclusion: The Bayesian network model may provide a relatively accurate prognostic prediction for ICC patients after curative intent resection and performed superior to the nomogram model.

Loss of H3K27 methylation identifies poor outcomes in adult-onset acute leukemia

Background

Acute leukemia is an epigenetically heterogeneous disease. The intensity of treatment is currently guided by cytogenetic and molecular genetic risk classifications; however these incompletely predict outcomes, requiring additional information for more accurate outcome predictions. We aimed to identify potential prognostic implications of epigenetic modification of histone proteins, with a focus on H3K4 and H3K27 methylation marks in relation to mutations in chromatin, splicing and transcriptional regulators in adult-onset acute lymphoblastic and myeloid leukemia.

Results

Histone 3 lysine 4 di- and trimethylation (H3K4me2, H3K4me3) and lysine 27 trimethylation (H3K27me3) mark expression was evaluated in 241 acute myeloid leukemia (AML), 114 B-cell acute lymphoblastic leukemia (B-ALL) and 14T-cell ALL (T-ALL) patient samples at time of diagnosis using reverse phase protein array. Expression levels of the marks were significantly lower in AML than in B and T-ALL in both bone marrow and peripheral blood, as well as compared to normal CD34+ cells. In AML, greater loss of H3K27me3 was associated with increased proliferative potential and shorter overall survival in the whole patient population, as well as in subsets with DNA methylation mutations. To study the prognostic impact of H3K27me3 in the context of cytogenetic aberrations and mutations, multivariate analysis was performed and identified lower H3K27me3 level as an independent unfavorable prognostic factor in all, as well as in TP53 mutated patients. AML with decreased H3K27me3 demonstrated an upregulated anti-apoptotic phenotype. In ALL, the relative quantity of histone methylation expression correlated with response to tyrosine kinase inhibitor in patients who carried the Philadelphia cytogenetic aberration and prior smoking behavior.

Conclusion

This study shows that proteomic profiling of epigenetic modifications has clinical implications in acute leukemia and supports the idea that epigenetic patterns contribute to a more accurate picture of the leukemic state that complements cytogenetic and molecular genetic subgrouping. A combination of these variables may offer more accurate outcome prediction and we suggest that histone methylation mark measurement at time of diagnosis might be a suitable method to improve patient outcome prediction and subsequent treatment intensity stratification in selected subgroups.

[Clinical value of extended radical resection for pT3 stage gallbladder cancer]

Objective: To investigate the clinical value of extended radical resection for stage pT3 gallbladder cancer (GBC). Methods: The clinical and pathological data of 323 patients with stage pT3 GBC who received regional radical resection or extended radical resection in 7 domestic hepatobiliary centers in China from January 2013 to December 2018 were retrospectively analyzed. The propensity score matching method was used to select 36 cases in each of the regional radical resection group (group A1) and the extended radical resection group (group B1). The surgical indicators and overall survival rates of the two groups were compared, and prognostic factors were analyzed. Results: The number of positive lymph nodes [2(0,3)] and the total number of lymph nodes removed [3(1,4)] in group B1 were both higher than those in group A1 [1(0,1), 4(2,7)] (all P<0.05). There was no significant difference in other clinical and pathological factors between the two groups (all P>0.05). The 1, 3, and 5-year survival rates of group A1 were 75%, 44%, and 29%, respectively, which were significantly higher than those of group B1 of 50%, 15%, and 11% (χ(2)=11.311, all P<0.001). Extensive radical resection (HR=2.161, 95%CI: 1.222-3.821), hepatic parenchymal invasion (HR=2.324, 95%CI: 1.305-4.139), positive lymph node rate ≥1/3 (HR=2.927, 95%CI: 1.641-5.220), and ⅢB/ⅣB staging (HR=3.325, 95%CI: 1.750-6.320) are risk factors for the prognosis of GBC patients (all P<0.05), of which extended radical resection (HR=1.969, 95%CI: 1.083-3.581) was an independent risk factor for prognosis (P<0.05). When the ratio of positive lymph nodes was<1/3 and the tumor invaded the hepatic parenchyma, the overall survival rate of group B1 was significantly lower than that of group A1 (all P<0.05). Conclusions: The overall survival rate in patients with stage pT3 GBC whose lymph node positive rate<1/3 and/or hepatic parenchymal invaded cannot be improved by extended radical resection. Extended radical resection is an independent risk factor for patient prognosis.

A novel monoclonal antibody against human B7-1 protects against chronic graft-vs.-host disease in a murine lupus nephritis model

Lupus nephritis (LN) is the most common complication that causes mortality in patients with systemic lupus erythematosus. The B7-1/B7-2 and CD28/cytotoxic T-lymphocyte associated protein 4 co-stimulatory pathway serves a key role in autoimmune disease and organ transplantation. The aim of the present study was to generate and characterize a monoclonal antibody (mAb; clone 4E5) against human B7-1 and to investigate its potential use for the treatment of LN. The results demonstrated that the 4E5 mAb was successfully generated and able to recognize both human and mouse B7-1. After injection of this mAb into a mouse model with chronic graft-vs.-host disease (cGVHD)-induced lupus-like disease, the expression of CD21, CD23, CD80 and CD86 on B220⁺ B-cells in the spleen, and the concentrations of serum autoantibodies and urine protein, were decreased. Direct immunofluorescence analysis of the kidneys revealed that immunofluorescence of immune complex deposits was weaker in the 4E5-treated mice and electron microscopy analyses of renal tissues indicated that pathological injury of the kidneys of 4E5-treated mice was decreased compared with that in the model control mice. The results of the present study demonstrated that inhibition of the B7-1/CD28 co-stimulatory signaling pathway with the 4E5 mAb may represent a promising strategy to decelerate the progression of LN that is induced by cGVHD with potential for use in the treatment of other autoimmune diseases.

[Application value of different lymph node staging system in predicting prognosis of patients with intrahepatic cholangiocarcinoma]

Objective: To examine the value of number of metastatic lymph nodes(NMLN), lymph node ratio(LNR) and log odds of metastatic lymph nodes(LODDS) in assessing the prognosis of patients with intrahepatic cholangiocarcinoma(ICC). Methods: The clinical and pathological data of 440 ICC patients who underwent curative-intent resection in 10 of Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected, and the deadline of follow-up was April 30th, 2019. Among them, 205 were males and 235 were females, with age of (57.0±9.9) years (range:23-83 years).Eighty-five cases (19.3%) had intrahepatic bile duct stones, and 98 cases (22.3%) had chronic viral hepatitis.The Kaplan-Meier method was used for survival analysis. The univariate and multivariate analysis were implemented respectively using the Log-rank test and Cox proportional hazard model. Results: A total of 440 patients underwent curative-intent resection and lymphadenectomy.R0 resection were achieved in 424 cases (96.4%) and R1 resection were in 16 cases (3.6%). The results of postoperative pathological examination showed that high, moderate and poor differentiation was 4.2%(18/426), 60.6%(258/426) and 35.2%(150/426), respectively.Adenocarcinoma was seen in 90.2%(397/440) and non-adenocarcinoma was seen in 9.8%(43/440), respectively. T stage: 2 cases (0.5%) with Tis, 83 cases(18.9%) with T1a, 97 cases(22.0%) with T1b, 95 cases(21.6%) with T2, 122 cases (27.7%) with T3 and 41 cases(9.3%) with T4.The overall median survival time was 24.0 months, and the 1-,3-, and 5-year survival rate was 74.3%, 37.7% and 18.3%, respectively. Lymphatic metastasis occurred in 175 patients(39.8%), the median total number of TNLE(M(Q(R))) was 6(5), the median number of NMLN was 0(1), the median number of LNR was 0 (0.33) and the median number of LODDS was -0.70(-0.92). Rerults of univariate analysis showed that combined stones, pathological differentiation, vascular invasion, LODDS, margin and T staging affected the prognosis (all P<0.05). Rerults of multivariate analysis showed that pathological differentiation, LODDS, margin, and T staging were independent risk factors affecting the prognosis of ICC patients (all P<0.05). Conclusion: LODDS could be used as an optimal prognostic lymph node staging index for ICC, and it is also an independent risk factor for survival after curative intent resection.

[Analysis of the relationship between the number of lymph nodes examined and prognosis for curatively resected gallbladder carcinoma: a multi-institutional study]

Objective: To examine the role of the number of lymph nodes examined(NLNE) on the prognosis of patients with curatively resected gallbladder carcinoma(GBC). Methods: The clinicopathological data and prognosis of 401 patients with GBC who underwent radical surgery from six institutions of China from January 2013 to December 2017 were analyzed retrospectively. There were 153 males(38.2%) and 248 females(61.8%), with age of (62.0±10.5) years (range: 30-88 years). Fifty-three patients(22.2%) were accompanied by jaundice. All patients underwent radical resection+regional lymphadenectomy.R0 or R1 resection was confirmed by postoperative pathological examination.The different cut-off values of NLNE were determined by the X-tile software, the optimal cut-off values were identified by analyzing the relationship between different cut-off values of NLNE with survival rate. Kaplan-Meier method was used for survival analysis. Univariate and multivariate analysis were implemented respectively using the Log-rank test and Cox proportional hazard model. Results: Among the 401 patients enrolled, 135 cases (33.6%) had lymphatic metastasis, of which 98 cases were in N1 stage(24.4%) and 37 cases were in N2 stage(9.2%).A total of 2 794 NLNE were retrieved, with a median count of 6 (5).The median positive lymph nodes count was 0 (1), and the median positive lymph nodes ratio was 0 (IQR, 0-0.2). Since the 12 and 15 were determined as the cut-off values by X-tile, all patients were divided into three groups of 1-11, 12-15 and ≥16.The 3-year survival rate of the three groups was 45.2%, 74.5%, 12.0% respectively, with statistically significant difference between three groups (χ(2)=10.94, P<0.01). The results of multivariate analysis showed that NLNE was an independent prognostic factor for overall survival (P<0.05). Further analysis was performed specifically for subgroup of T stages. For T1b patients, the prognosis of the NLNE with 1-7 group was significantly better than that of the ≥8 group(χ(2)=4.610, P<0.05). For T2 patients, the prognosis of the TLNE ≥7 group was significantly better than that of 1 -6 group (χ(2)=4.287, P<0.05). For T3 and T4 patients, the prognosis of the TLNE with 12 - 15 group was significantly better than that of 1 -11 group (χ(2)=5.007, P<0.01) and ≥16 group (χ(2)=10.158, P<0.01). Conclusions: The NLNE is an independent factor affecting the prognosis of patients with GBC.For patients with stage T1b,8 lymph nodes should be retrieved; for patients with stage T2,extensive dissection of more than 6 lymph nodes can significantly improve the prognosis.For advanced patients (stages T3 and T4), extensive dissection with 12-15 lymph nodes is recommended. However, it fails to get more survival benefits by dissecting more than 16 lymph nodes.

[Discussion on pT3 staging in TNM staging of AJCC 8(th) edition gallbladder carcinoma]

Objective: To discuss the rationality of stage pT3 in the AJCC 8(th) TNM criteria of gallbladder carcinoma. Methods: A retrospective study was performed to analyze the clinical and pathological data of 88 patients with pT3 gallbladder carcinoma admitted to Department of Second Biliary Surgery of Eastern Hepatobiliary Surgery Hospital, affiliated to Naval Medical University from May 2013 to September 2018.pT3 stage tumors were divided into two groups: (1) pT3a stage: tumors had penetrated serosa but not directly invaded liver and/or an adjacent organ or structure; (2) pT3b stage: tumor penetrating serosa and directly invaded liver and/or an adjacent organ or structure. There were 45 patients with pT3a stage, including 15 males and 30 females, aged 36 to 80 years, with a median age of 59 years; 43 patients with pT3b, including 24 males and 19 females, aged 41 to 78 years old, median aged 63 years old.Patients with pT3a and pT3b were further divided into two groups respectively: radical resection group and extended radical resection group according to surgical radicalization. Independent sample t-test was used for comparison between two groups with normal distribution measurement data. Wilcoxon rank sum test was used between groups of non-normally distributed measurement data.The comparison of the count data was performed by χ(2) test or Fisher exact probability method. Survival analysis was performed using Kaplan-Meier method, and survival rate was compared using Log-rank test. Results: (1)Serum total bilirubin(15.6(90.3)mmol/L), albumin(40.2(4.8)mmol/L), and CA19-9(132.90(455.78)U/ml) levels in pT3b patients were higher than that in pT3a patients(10.2(6.8)mmol/L, 41.8(4.9)mmol/L, 14.35(36.27)U/ml), respectively(Z=-3.816, -1.966, -3.739, all P<0.05),postoperative complication rate in pT3b patients(24.4%) was higher than that in pT3a patients(8.9%)(P<0.05),postoperative hospital stay(12(7)days) and overall hospital stay((26±17)days) of pT3b patients were longer than that of pT3a patients((10±5) days and (19±7)days) (P<0.05). (2) The 1-, 3-, 5-year survival rates of pT3b and pT3a patients were 53%,22%,22% and 69%, 46%,38%,and the median survival time was 13 months and 26 months, respectively. The difference in survival rates between the two groups was statistically significant(χ(2)=5.117, P=0.024). (3)The 1-, 3-year survival rates of extended radical resection group(n=19) and radical resection group(n=24) in the pT3b stage were 73%, 36% and 28%, 7%, respectively.The survival time was 20 months and 9 months,respectively,and the difference in survival rates between the two groups was statistically significant(χ(2)=4.976, P=0.026). Conclusions: pT3 gallbladder carcinoma could be further subdivided into pT3a stage and pT3b stage based on the TNM criteria of AJCC 8(th) gallbladder carcinoma. Extended radical resection for pT3b gallbladder carcinoma should be further considered after comprehensive assessment of the patient's basic condition and surgical tolerance.

[Applicational value of modified pancreaticojejunostomy and risk factors of pancreatic fistula following pancreaticoduodenectomy]

Objective: To compare the efficacy of modified pancreaticojejunostomy with traditional pancreaticojejunostomy following pancreaticoduodenectomy, and to investigate the risk factors of postoperative pancreatic fistula. Methods: Clinical data of 68 patients who underwent pancreaticoduodenectomy between October 2017 and October 2018 at the Second Department of Biliary Tract Surgery, Eastern Hepatobiliary Surgery Hospital was retrospectively collected and analyzed.According to the method of pancreaticojejunostomy, the patients were divided into two groups: modified pancreaticojejunostomy group (34 patients) and traditional pancreaticojejunostomy group (34 patients). There were 18 males and 16 females, aged (60.4±9.6) years of modified pancreaticojejunostomy groups; there were 17 males and 18 females, aged (58.9±10.9) years of traditional pancreaticojejunostomy group. The major postoperative complications such as pancreatic fistula were compared between the two groups, and the risk factors of postoperative pancreatic fistula were analyzed by univariate and multivariate analyses. Results: All of the 68 operations were successfully completed. The overall incidence of postoperative complications was 51.5% (35/68). The incidence of postoperative pancreatic fistula was 13.2% (9/68), of which all were cases of grade B.There were 16 patients (23.5%) occurred with abdominal infection, and 11 patients (16.2%) occurred with delayed gastric emptying, including 1 case of grade A, 1 case of grade B and 9 cases of grade C.And 9 patients (13.2%) occurred with postoperative bleeding was, including 2 cases of mild bleeding, 5 cases of moderate bleeding, and 2 cases of severe bleeding.Biliary leakage occurred in one patient (1.5%) and chylous leakage occurred in two patients (2.9%). The modified pancreaticojejunostomy could significantly reduce the incidence of postoperative bleeding compared with control group (χ(2)=4.610, P=0.032). And there were no significant differences for other postoperative complications between the two groups (all P>0.05). According to the results of univariate analysis: age, intraoperative bleeding and diameter of pancreatic tube were related factors affecting postoperative pancreatic fistula (P=0.025, 0.019, 0.017, respectively). The results of multivariate analysis showed that intraoperative bleeding>400 ml and diameter of pancreatic tube <3 mm were independent risk factors of pancreatic fistula following pancreaticoduodenectomy (P=0.025, 0.008, respectively). Conclusion: The modified pancreaticojejunostomy is feasible with advantages of reducing postoperative bleeding following pancreaticoduodenectomy.

[Pilot study of the relationship between clinical classification of gallbladder cancer and prognosis: a retrospective multicenter clinical study]

Objectives: To propose a novel clinical classification system of gallbladder cancer, and to investigate the differences of clinicopathological characteristics and prognosis based on patients who underwent radical resection with different types of gallbladder cancer. Methods: The clinical data of 1 059 patients with gallbladder cancer underwent radical resection in 12 institutions in China from January 2013 to December 2017 were retrospectively collected and analyzed.There were 389 males and 670 females, aged (62.0±10.5)years(range:22-88 years).According to the location of tumor and the mode of invasion,the tumors were divided into peritoneal type, hepatic type, hepatic hilum type and mixed type, the surgical procedures were divided into regional radical resection and extended radical resection.The correlation between different types and T stage, N stage, vascular invasion, neural invasion, median survival time and surgical procedures were analyzed.Rates were compared by χ(2) test, survival analysis was carried by Kaplan-Meier and Log-rank test. Results: Regional radical resection was performed in 940 cases,including 81 cases in T1 stage,859 cases in T2-T4 stage,119 cases underwent extended radical resection;R0 resection was achieved in 990 cases(93.5%).The overall median survival time was 28 months.There were 81 patients in Tis-T1 stage and 978 patients in T2-T4 stage.The classification of gallbladder cancer in patients with T2-T4 stage: 345 cases(35.3%)of peritoneal type, 331 cases(33.8%) of hepatic type, 122 cases(12.5%) of hepatic hilum type and 180 cases(18.4%) of mixed type.T stage(χ(2)=288.60,P<0.01),N stage(χ(2)=68.10, P<0.01), vascular invasion(χ(2)=128.70, P<0.01)and neural invasion(χ(2)=54.30, P<0.01)were significantly correlated with the classification.The median survival time of peritoneal type,hepatic type,hepatic hilum type and mixed type was 48 months,21 months,16 months and 11 months,respectively(χ(2)=80.60,P<0.01).There was no significant difference in median survival time between regional radical resection and extended radical resection in the peritoneal type,hepatic type,hepatic hilum type and mixed type(all P>0.05). Conclusion: With application of new clinical classification, different types of gallbladder cancer are proved to be correlated with TNM stage, malignant biological behavior and prognosis, which will facilitate us in preoperative evaluation,surgical planning and prognosis evaluation.

[Effects of 3-methyladenine on airway inflammation, airway hyperresponsiveness and mucus secretion in asthmatic mice]

Objective: To investigate the effects of 3-methyladenine on airway inflammation, airway hyperresponsiveness and mucus secretion in asthmatic mice, and to explore its mechanism. Methods: C57BL/6J female mice were randomly divided into normal control group (PBS), OVA group(OVA), OVA with 3-methyladenine group (OVA+3-MA), and OVA with 4-phenylbutyrate group (OVA+4-PBA). OVA group, OVA+3-MA group and OVA+4-PBA groups were all sensitized and challenged with OVA to establish asthmatic models, while PBS group was given PBS as a control. At 2 h before challenge, OVA+3-MA group was intraperitoneally injected with 3-methyladenine, and OVA+4-PBA group was intraperitoneally injected with 4-phenylbutyrate. Airway hyperresponsiveness, eosinophils, and pathological changes of pulmonary tissue (hematoxylin-eosin, HE staining) were measured to confirm the establishment of asthmatic models. Sections of pulmonary tissue were also stained with Masson and PAS. The expression level of LC3B was measured by immunofluorescence and Western blot. The Beclin1, Muc5ac, Atf6, Chop and Bip proteins in lung tissues were detected by Western blot. Results: The Penh value, and eosinophils in BALF in OVA group was significantly increased compared with PBS group (P<0.05). The Penh value in OVA+3-MA group and OVA+4-PBA group were significantly decreased compared with the OVA group at the concentration of 6.25 g/L, 12.50 g/L, 25.00 g/L, and 50.00 g/L of methacholine (all the P<0.05), and the eosinophils were also significantly decreased compared with the OVA group (P<0.05). Pulmonary histology revealed that OVA group showed high levels of inflammatory cell infiltration of bronchi and lung vessels, alveolar septal thickening, structural destruction, smooth muscle thickening, collagen deposition, and goblet cell hyperplasia. The levels of inflammatory cell infiltration of bronchi and lung vessels, alveolar septal thickening, structural destruction, smooth muscle thickening, collagen deposition, and goblet cell hyperplasia in OVA+3-MA group and OVA+4-PBA group were significantly lower than the OVA group, while the PBS group was normal. Compared with PBS group, the expression of LC3 Ⅱ/Ⅰ, Beclin1, Muc5ac, Atf6, Chop and Bip proteins in lung tissues in the OVA group were significantly increased (1.09±0.04 vs 0.34±0.09, P<0.05; 0.18±0.01 vs 0.06±0.01, P<0.05; 1.90±0.38 vs 0.46±0.11, P<0.05; 1.67±0.18 vs 0.41±0.08, P<0.05; 2.96±0.45 vs 1.11±0.10, P<0.05; 2.07±0.34 vs 0.49±0.17, P<0.05, respectively). Compared with the OVA group the expression of LC3 Ⅱ/Ⅰ, Beclin1, Muc5ac, Atf6, Chop and Bip proteins in lung tissues in the OVA+3-MA group and OVA+4-PBA group were significantly decreased (0.46±0.07 vs 1.09±0.04, 0.63±0.03 vs 1.09±0.04, both P<0.05; 0.11±0.02 vs 0.18±0.01, 0.12±0.02 vs 0.18±0.01, both P<0.05; 0.72±0.22 vs 1.90±0.38, 0.57±0.13 vs 1.90±0.38, both P<0.05; 1.06±0.12 vs 1.67±0.18, 1.02±0.12 vs 1.67±0.18, both P<0.05; 1.67±0.21 vs 2.96±0.45, 1.10±0.15 vs 2.96±0.45, both P<0.05; 1.03±0.11 vs 2.07±0.34, 0.97±0.10 vs 2.07±0.34, both P<0.05). Conclusion: 3-MA was shown to inhibit airway inflammation, airway hyperresponsiveness and mucus secretion in mice with bronchial asthma, and the mechanism may be related to inhibiting autophagy, and then inhibiting endoplasmic reticulum stress.

[A multicenter retrospective study for the prognosis of T1b stage gallbladder carcinoma underwent different surgical procedure]

Objective: To explore the prognosis of patients with T1b stage gallbladder carcinoma underwent different surgical procedure. Methods: The clinicopathological data of 97 patients with T1b stage gallbladder carcinoma came from 8 clinical centers from January 2010 to December 2016 and 794 patients who were admitted to the SEER database of USA from January 1973 to December 2014 were analyzed.There were 891 patients including 254 males and 637 females (1.0∶2.5) with age of (69.5±12.0)years. There were 380 patients who were less than 70 years old, 511 patients who were more than 70 years old. And there were 213 patients with the diameter of tumor less than 20 mm, 270 patients with the diameter of tumor more than 20 mm, 408 patients were unclear. There were 196 patients with well differentiation, 407 patients with moderately differentiation, 173 patients with poorly differentiation, 8 patients with undifferentiated, 107 patients were unclear. In the 891 patients with T1b stage gallbladder carcinoma, there were 562 cases accepted the simple cholecystectomy, 231 cases with simple cholecystectomy plus lymphadenectomy, and 98 cases with radical cholecystectomy. The time of follow-up were until June 2017. χ(2) test was used to analyze the enumeration data, rank-sum test was used to analyze the measurement data, the analyses of prognostic factors were used Cox proportional hazards model, the survival analysis was performed using Kaplan-Meier method. Results: The results of Cox proportional hazards model indicated, age, differentiation, surgical procedure were the risk factors of prognostic(1.929(1.594-2.336), P<0.01; 1.842(1.404-2.416), P<0.01; 1.216(0.962-1.538), P<0.01). The results of Kaplan Meier test indicated, the overall survival of T1b stage gallbladder carcinoma were (85.5±3.8)months, the overall survival of patients with simple cholecystectomy were (71.3±4.4)months, the overall survival of patients with cholecystectomy plus lymphadenectomy were(87.6±5.8)months, and the overall survival of patients with radical cholecystectomy were(101.7±9.3)months. The overall survival of patients with cholecystectomy plus lymphadenectomy and radical cholecystectomy were more than simple cholecystectomy(P<0.05). There were 329 patients with Lymph nodes examined in and after operations(231 patients with cholecystectomy plus lymphadenectomy, 98 patients with radical cholecystectomy). There were 265 patients with negative lymph node metastasis, the overall survival were(98.3±4.2)months. There were 64 patients with positive lymph node metastasis, the overall survival were(75.5±3.1)months. The overall survival of 38 patients with cholecystectomy plus lymphadenectomy were(62.7±2.6) months, and 26 patients with radical cholecystectomy were (82.2±3.7)months. The overall survival of patients with radical cholecystectomy were more than cholecystectomy plus lymphadenectomy(P<0.05). Conclusions: The T1b stage gallbladder carcinoma patients with cholecystectomy plus lymphadenectomy or radical cholecystectomy has improved the prognosis comparing with simple cholecystectomy, significantly. When lymph node metastasis occurs, radical cholecystectomy has improved the prognosis comparing with cholecystectomy plus lymphadenectomy.

[The survival prediction model of advanced gallbladder cancer based on Bayesian network: a multi-institutional study]

Objective: To investigate the clinical value of Bayesian network in predicting survival of patients with advanced gallbladder cancer(GBC)who underwent curative intent surgery. Methods: The clinical data of patients with advanced GBC who underwent curative intent surgery in 9 institutions from January 2010 to December 2015 were analyzed retrospectively.A median survival time model based on a tree augmented naïve Bayes algorithm was established by Bayesia Lab software.The survival time, number of metastatic lymph nodes(NMLN), T stage, pathological grade, margin, jaundice, liver invasion, age, sex and tumor morphology were included in this model.Confusion matrix, the receiver operating characteristic curve and area under the curve were used to evaluate the accuracy of the model.A priori statistical analysis of these 10 variables and a posterior analysis(survival time as the target variable, the remaining factors as the attribute variables)was performed.The importance rankings of each variable was calculated with the polymorphic Birnbaum importance calculation based on the posterior analysis results.The survival probability forecast table was constructed based on the top 4 prognosis factors. The survival curve was drawn by the Kaplan-Meier method, and differences in survival curves were compared using the Log-rank test. Results: A total of 316 patients were enrolled, including 109 males and 207 females.The ratio of male to female was 1.0∶1.9, the age was (62.0±10.8)years.There was 298 cases(94.3%) R0 resection and 18 cases(5.7%) R1 resection.T staging: 287 cases(90.8%) T3 and 29 cases(9.2%) T4.The median survival time(MST) was 23.77 months, and the 1, 3, 5-year survival rates were 67.4%, 40.8%, 32.0%, respectively.For the Bayesian model, the number of correctly predicted cases was 121(≤23.77 months) and 115(>23.77 months) respectively, leading to a 74.86% accuracy of this model.The prior probability of survival time was 0.503 2(≤23.77 months) and 0.496 8(>23.77 months), the importance ranking showed that NMLN(0.366 6), margin(0.350 1), T stage(0.319 2) and pathological grade(0.258 9) were the top 4 prognosis factors influencing the postoperative MST.These four factors were taken as observation variables to get the probability of patients in different survival periods.Basing on these results, a survival prediction score system including NMLN, margin, T stage and pathological grade was designed, the median survival time(month) of 4-9 points were 66.8, 42.4, 26.0, 9.0, 7.5 and 2.3, respectively, there was a statistically significant difference in the different points(P<0.01). Conclusions: The survival prediction model of GBC based on Bayesian network has high accuracy.NMLN, margin, T staging and pathological grade are the top 4 risk factors affecting the survival of patients with advanced GBC who underwent curative resection.The survival prediction score system based on these four factors could be used to predict the survival and to guide the decision making of patients with advanced GBC.

[Preparation of mouse monoclonal antibody against human B7-1 (CD80) and its inhibitory effect on tumor cells in vitro]

Objective To prepare a mouse anti-human B7-1 monoclonal antibody (mAb) and study its effect on growth and migration of tumor cells naturally expressing human B7-1 (CD80) molecular in vitro. Methods BALB/c mice were immunized with L929-B7-1 cells transfected with human B7-1 gene and mAbs were prepared by B lymphocyte hybridoma technology. Then, the recognition ability of mAb to tumor cells expressing membrane B7-1 was detected by flow cytometry. Different concentrations of mAbs (5, 10, 20, 40 μg/mL) were added into Daudi, Raji, and 8266 cells to investigate the anti-proliferation effect by MTT assay. Transwell^TM assay was used to analyze the effect of mAb on tumor cell migration in vitro, and flow cytometry was used to analyze the induction effect of mAb on apoptosis of tumor cells. Results A hybridoma cell stably secreting mouse anti-human B7-1 mAb was successfully obtained and named 5G10. The binding rates to tumor cells Daudi, Raji, 8266, U266, Bel-7402 and MCF-7 were (96.3±2.12)%, (95.7±1.79)%, (96.8±2.48)%, (23.2±2.35)%, (1.68±0.35)%, (0.55±0.04)%, respectively. Compared with control group, 20 μg/mL 5G10 mAb significantly inhibited the proliferation of Daudi, Raji and 8266 cells, reduced their migration, and increased cell apoptosis rates remarkably. Conclusion The 5G10 mAb can specifically recognize and bind to membrane B7-1, inhibit the proliferation, migration and promotes apoptosis of tumor cells in vitro.

High expression of VRK1 is related to poor prognosis in glioma

Vaccinia-related kinase 1 (VRK1) is a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases, which phosphorylates several transcription factors and has been postulated to be involved in regulation of cell proliferation. However, it remains unclear whether aberrant expression of VRK1 is related to the development of glioma. In this study, we aimed to investigate the clinical significance of VRK1 expression in human glioma and its biological function in glioma cells. Western blot and immunohistochemical analysis revealed that VRK1 was highly expressed in glioma tissues and cell lines. In addition, the expression level of VRK1 was positively correlated with glioma pathological grade, as well as Ki-67 expression. Kaplan-Meier analysis revealed that patients with high VRK1 expression was associated with a poorer prognosis. To determine whether VRK1 could regulate the proliferation of glioma cells, we transfected glioma cells with interfering RNA target VRK1, then investigated cell proliferation with cell counting kit (CCK) -8, flow cytometry assays and colony formation analyses. Our results indicated that knockdown of VRK1 would inhibit the proliferation of glioma cells. Besides, reduced expression of VRK1 could induce the apoptosis of glioma cells. On the basis of these findings, we suggested that VRK1 might be a promising prognostic biomarker of glioma.

A monoclonal antibody against CD86 and its protection in a murine lupus nephritis model of chronic graft-versus-host disease

CONTEXT

Lupus nephritis is the most common complication that causes the death of systemic lupus erythematosus patients. CD28/CTLA4 and their ligands CD80 or CD86 costimulatory pathway play a pivotal role in autoimmune disease and organ transplantation.

OBJECTIVES

We generated a monoclonal antibody (clone 1D1) against human CD86 (1D1) that could recognize both human and mouse CD86, and blocked the CD86/CD28 costimulatory pathway with our mAb on a murine lupus nephritis model induced with chronic graft-versus-host disease (cGVHD).

MATERIALS AND METHODS

Experimental lupus nephritis mice were induced with cGVHD, and splenocyte population were analyzed by flow cytometry. Autoantibodies and proteinuria were detected to evaluate the severity of lupus nephritis. The change of histopathology was observed by microscopy, fluorescence microscopy and electron microscopy.

RESULTS

we successfully generated a monoclonal antibody against human CD86(1D1). 1D1 mAb could recognize not only human CD86, but also mouse CD86. 1D1 was applied to the cGVHD-induced experimental lupus nephritis model, and our study found the production of ANA and anti-dsDNA in the 1D1-treated group was lower than those in IgG-treated group after four weeks. The pathological injure of kidney in the 1D1-treated group was lighten than that in IgG-treated group.

DISCUSSION AND CONCLUSIONS

Our data showed that blockade of CD86/CD28 with 1D1 induced a significant remission of proteinuria, production of autoantibodies, immune complex deposition and renal parenchyma lesions in experimental mice. Anti-CD86 Abs might be a potential method for immune therapy in autoimmune diseases and transplantation.

Characterization of a PRISTANE-induced lupus-associated model in the non-human primate cynomolgus monkey

BACKGROUND

Lupus is an autoimmune disease with complex syndrome. Rodent models have limitations for recapitulating the spectrum of the disease. A more powerful translational model is desirable.

METHOD

Lupus-associated model in cynomolgus monkeys was induced by two intraperitoneal injections of 2, 6, 10, 14-tetramethylpentadecane (PRISTANE). Lupus-specific biomarkers and manifestations over a 246-day period were observed at multilevel. To visualize and quantify kidney function in real time, contrast-enhanced ultrasound was used.

RESULTS

The indicative biomarkers and manifestations fulfilled major diagnosis criteria according to the "Criteria of Lupus" of the American College of Rheumatology. Significant changes in time-intensity curve parameters were observed, indicating impaired renal function and the method as a feasible, non-invasive diagnostic method in primate model.

CONCLUSIONS

We successfully induced lupus-associated model with systemic lupus syndrome. This primate model can be a valuable translational model for further pathogenesis and symptomology studies and for exploring therapeutic candidates.

[CXCR3 monoclonal antibody inhibits the proliferation and migration of MCF-7 cells and HepG2 cells in vitro]

OBJECTIVE

To study the effects of chemokine (C-X-C motif) receptor 3 (CXCR3) monoclonal antibody (mAb) on the proliferation and migration of MCF-7 and HepG2 cells in vitro.

METHODS

Ascites of CXCR3 mAb was prepared at first. MCF-7 and HepG2 cells with high expressions of CXCR3 were screened by flow cytometry. MTT assay was used to detect the effects of CXCR3 mAb on the proliferation of MCF-7 and HepG2 cells in vitro in the absence/presence of interferon-inducible T-cell alpha chemoattractant (I-TAC). Transwell™ assay was performed to investigate the effects of CXCR3 mAb on the migration of MCF-7 and HepG2 cells in vitro in the absence/presence of I-TAC.

RESULTS

The expression rate of CXCR3 on MCF-7 and HepG2 cells were 83.5% and 96.2%, respectively. 50 mg/mL CXCR3 mAb significantly inhibited the proliferation and migration of MCF-7 and HepG2 cells, and also inhibited the promoting effect of I-TAC on the proliferation and migration of MCF-7 and HepG2 cells in vitro.

CONCLUSION

CXCR3 mAb can significantly inhibit the proliferation and migration of the tumor cells highly expressing CXCR3 in vitro.

[Gene cloning, expression and binding activity of anti-CD86 scFv]

OBJECTIVE

To construct and express the single chain variable fragment (scFv) against human CD86 in CHO cells, and observe its biological functions of binding with antigen.

METHODS

The V(H); and V(L); genes were cloned by RT-PCR from a murine hybridoma cell line 1D1, which produced the monoclonal antibody (mAb) against human CD86. The CD86-scFv gene was integrated into eukaryotic expression vector to construct pIREST2-EGFP/scFv. CHO cells were transfected by pIREST2-EGFP/scFv plasmid with Lipofectamine(TM); 2000 and then were selected by G418. We used IMAC affinity chromatography to purify CD86-scFv and quantified its concentration by BCA method. Then the identification of CD86-scFv binding to membrane CD86 was performed through competitive inhibition assay. In addition, the growth inhibition effect of CD86-scFv on Raji cells was detected via MTT assay.

RESULTS

One cell line stably expressing CD86-scFv was obtained. The CD86-scFv could identify CD86 molecules on L929-CD86, Raji and Daudi cells, and the positive rates were 67.0%, 72.3% and 80.5%, respectively. CD86-scFv showed the competitive binding to murine parent antibody 1D1. Moreover, CD86-scFv inhibited the growth of Raji cells and the inhibition rate was 28.3% 72 h after 20 μg/mL CD86-scFv was added into Raji cells.

CONCLUSION

CD86-scFv has been successfully expressed in CHO cells (named SA-IV) and the antibody shows a good biological function of recognizing CD86 and inhibiting the growth of Raji cells.

[Construction of 3D model of CD28 chimeric antibody with its antigen docked]

AIM

To construct a 3D model of the chimeric antibodies (AntiCD28: ch-2F5) with corresponding antigen molecule docked to theoretically verify the rationality of the binding of antibody with its antigen and to provide a method of 3D identification between antigen and antibody and spatial structure analysis.

METHODS

We analyzed the sequence by submitting it to http://www.ncbi.nlm.nih.gov/ and made a comparison using integratly the 3 databases of GenBank, Protein data bank and GENO-3D. The 3D model was constructed by Swiss-model homology modeling server and molecular docking online was performed by GRAMM-X Protein Docking Web Server. Chimeric heavy chain, light chain, heavy-light chain complex, heavy-light chain and antigen complex were displayed and photographed by the Chimera Software. Meanwhile, the spatial structures of heavy, light chains, variable region, constant region, CDR and frame area were marked by different colours respectively to exhibit the 3D structure on every side.

RESULTS

The 3D structure of the heavy-light chain and antigen complex we constructed was consistent well with the theory of antigen binding to antibody molecules.

CONCLUSION

The structure of the chimeric antibody we constructed with the bioinformatic method was in accordance with the general structure of antibody, and its antigen binding site was also consistent with the molecular theory. Thus, the model helps to analyze the 3D structure of antibody and antigen-antibody interaction.

[Expression and antigen binding activity of anti-human CD86 diabody]

AIM

To construct a recombinant eukaryotic expression vector of anti-human CD86 diabody gene and express anti-CD86 diabody through Chinese hamster ovary (CHO) cells, then analyze the capability of the diabody to recognize the tumor cells expressing CD86 and its biological effect.

METHODS

The antibody heavy and light chain viable region gene (V(H); and V(L);) were cloned from hybridoma cell 1D1 which secreted anti-human CD86 monoclonal antibody. Anti-human CD86 diabody gene V(H);-(GGGGS)-V(L); was constructed by SOE-PCR. Then we inserted it into eukaryotic expression vector to construct a recombinant vector pIRES2-EGFP/CD86-diabody. The recombinant vector was transfected into CHO cells with Lipofectamine(TM); 2000, and the cell clones secreting CD86 diabody were screened by G418. We used IMAC to purify CD86 diabody and quantified its concentration by BCA method. The capability of the diabody to recognize the CD86 expressed on Raji and Daudi was analyzed through flow cytometry. After Raji cells were treated with CD86 diabody for 72 h, its proliferation inhibiting effect was investigated by MTT assay.

RESULTS

We have obtained one CHO cell line that stably secreted CD86 diabody. The concentration of CD86 diabody after purification was 5.24 mg/L. The positive rates of CD86 diabody to recognize Raji and Daudi were 77.2% and 70.6%, respectively. After CD86 diabody treatment for 72 h, the inhibition rate of Raji cells was 37%.

CONCLUSION

The anti-human CD86 diabody which we obtained successfully could recognize CD86 expressed on tumor cells specifically, and inhibit the proliferation of these tumor cells effectively.

[Effect of CD80-scFv on recognition of CD80 molecule and proliferation of different tumor cells in vitro]

AIM

To prepare CD80-scFv in CHO cells and investigate its effect on the recognition and proliferation of different tumor cells.

METHODS

The CD80-scFv was purified from culture supernatant without fetal calf serum (FCS) by IMAC affinity chromatography, and then bound to CD80 molecule on the Daudi, U251, A375 and 8266 cells detected by flow cytometry. Different concentrations of CD80-scFv were added in the training system of different tumor cells, and we analyzed the influence on the proliferation of these cells by MTT assay. With 8266 cells which expressed CD80 highly and were treated by mitomycin firstly as the APC, and human PBMC as the effect cells, we analyzed the influence of the CD80-scFv on the proliferation of PBMC by blocking the co-stimulatory signal.

RESULTS

The concentration of CD80-scFv purified from FCS was about 6.67 mg/L and the binding rate of CD80-scFv with Daudi, U251, A375, 8266 and U266 were 96.8%, 39.6%, 20.5%, 99.9% and 3.8%, respectively. CD80-scFv suppressed the proliferation of Daudi and 8266 cells which expressed CD80 highly, and the inhibition rate of Daudi and 8266 cells cultured with CD80-scFv (the final concentration was 25 μg/mL) was 24.04% and 24.16%, respectively. Additionally, the antibody suppressed the proliferation of PBMC by blocking the co-stimulatory signal mediated by CD80-CD28.

CONCLUSION

CD80-scFv can recognize CD80 molecule and suppress the proliferation of tumor cells which express CD80 highly.

4-1BB-mediated signals confer protection against folic acid-induced nephrotoxicity

BACKGROUND

The role of co-stimulatory molecules in renal diseases has been previously examined, however, little is known about the role of 4-1BB in the context of renal diseases resulting from nonimmune-mediated tubulointerstitial fibrosis. Folic acid induced Nephrotoxicity (FAN) in mice was used to explore the role of 4-1BB in this setting.

METHODS

CD1 mice were treated with folic acid and kidneys subsequently examined using histochemistry, in addition to defining T cell profiles and evaluating renal function. Increased CD3+ and CD4+ T lymphocytes present in blood and spleen at day 3 suggested immunopathological reactions during the early stages of FAN and decreased CD3+ and CD4+ T lymphocytes on day 14 were characteristic of an immunocompromised state observed during the late stages of FAN.

RESULTS

After 14 days of co-treatment with agonistic anti-4-1BB monoclonal antibodies, renal tubulointerstitial lesions were reduced. Renal function was improved, with Bun scores decreasing (p<0.01) and sCr levels decreasing (p<0.01). CD3+ and CD4+ T lymphocytes levels were increased during the early stages of disease in FA treated mice and reduced to the normal level in the 4-1BB-treated mice. CD3+ and CD4+ T lymphocytes levels were decreased in FA treated mice and returned to baseline in the 4-1BB-treated mice during later stages.

CONCLUSIONS

Data presented in this report demonstrated that 4-1BB signals had immunoregulatory effects that attenuated early immune-mediated pathology and reversed the immunocompromised state observed during the later stages of disease.

[Changes in the expression of T lymphocyte subsets in ageing mice induced by D-galactose]

AIM

To explore the changes and significance of spleen T cell subsets in ageing mice induced by D-galactose.

METHODS

Ageing mice model was successfully established by 100 g/L D-galactose. The content of IFN-γ and IL-4 in serum was measured by ELISA. T cell subsets were detected by Immunofluorescence technique and flow cytometry.

RESULTS

The content of IFN-γ and IL-4 in the serum was decreased of model group (P<0.01). The naive T cell related molecule, CD45RA was decreased(P<0.05). T cell activation-related molecule, CD25 was decreased(P<0.05). The Foxp3 in CD4(+);CD25(+); T cell was increased(P<0.01).

CONCLUSION

In spleen of the ageing mice, the percentage of naive and active T cell are decreased, but The percentage of CD4(+); Tr subset is increased.

[The changes of spleen B cells of D-galactose-induced aging mice]

AIM

This paper is to analyze the changes of important membrane type molecules of the spleen B cells and their significance on the basis of biology identification by establishing subacute aging mice model with D-galactose.

METHODS

Health Kunming mice are injected with 100 ng/L D-galactose, 0.25 mL/20 g, once per day, for 42 days consecutively, into their back necks. The animals' living conditions and biological behaviors are observed everyday and the dynamic changes of their weight are measured regularly. The biology identification of aging model mice is conducted by means of measuring the SOD viability and malondialdehyde (MDA) concentration in serum; the analysis of the activation- and memory-related important membrane type molecules of spleen cells is carried out with immune fluorescence and flow cytometry; the analysis of the concentration of IL-4 in serum is conducted by ELISA.

RESULTS

Building a successful subactue aging mice model.The results of immune fluorescence and flow cytometry showed that CD20(+); was 56.8%, CD40(+); was 43.6%, CD20(+);CD45RA(+);B was 14.04%, CD40(+);CD45RA(+);B was 35.4%, CD20(+);CD86(+);B was 2.25%, CD40(+);CD86(+);B was 4.38%, CD20(+);CD196(+);B was 10.68%, and CD40(+);CD196(+);B was 10.98%. The results of ELISA showed that the average level of IL-4 in serum was 7.93 ng/L. The statistical analysis showed that the expressions of CD20, CD40, CD45RA, and CD86 of the spleen cells of the model control group and the average level of IL-4 in serum were lower than the normal control group(P<0.05)while CD196 was higher than the normal control group(P<0.01).

CONCLUSION

In the body's aging process, the expressions of the activation- and memory-related important membrane type molecules of spleen cells change, activated cells reduce, memory cells increase, and the expression of IL-4 in serum drop, resulting in the immune system function disorder.

[Changes and effects of significant membrane molecules on thymic T cell of aging mice induced by D-galactose]

AIM

To establish subacute aging mice model by D-galactose and to explore the changes and effects of significant membrane molecules on thymic T cell.

METHODS

Female Kunming mice of 8 weeks old were injected with D-galactose of 12.5 mL/(kg.d) by subcutaneous in scruff for 42 days. The animals' living conditions and biological behaviors were observed everyday.SOD activities and MDA content of serum were measured to determine whether the aging model was successfully established.On the basis of successfully establishing aging model, detect the significant membrane molecules of thymic T cell by Immunofluorescence technique and Flow Cytometer.

RESULTS

During the 42 days, gradually, the model mice showed bending body, loose skin, slow action and so on.The activities of SOD in the serum were significantly decreased(P<0.01), and the content of MDA in the serum was significantly increased(P<0.01). The thymic naive T cell significant molecule, CD45RA was decreased(P<0.05). T cell activation-related molecules, CD28 and CD25 were both decreased(P<0.05), and PD-1 was significantly increased(P<0.01). The memory T cell significant molecule, CD196 was increased, but was not significantly compared to the control mice.

CONCLUSION

The D-galactose subacute aging mice model was successfully established.The naive and active T cell were decreased and the memory T cell was increased in the thymic of the aging.

[Mouse anti-human CXCR3 mAb preparation and its biological function]

AIM

Obtain hybridoma cell line with continuing expression of mouse anti-human CXCR3 mAb, investigate expression characteristics of human CXCR3 and how CXCR3 signal transduction function on L929-huCXCR3 and colon carcinoma cell lines transfer and growth.

METHODS

Taking L929-huCXCR3 cell with high expression of human CXCR3 membrane molecule as immunogen to immunize BALB/c mouse, we fused immunized mouse spleen cell with myeloma cell Sp2/0 of its same germ line, then used L929-huCXCR3 as screening cell and empty vector transfected cell L929-mock as negative control. Obtained hybridoma cell line with continuing secretion of anti-human CXCR3 mAb through flow cytometry. We used Ig subclass type rapid qualitation indicator paper method and indirect immunofluorescence to identify obtained hybridoma cell line and mAb, indirect immunofluorescence to analyze CXCR3 expression on tumor cell surface, Transwell isolation cabin to assess effect on L929-huCXCR3 and colon carcinoma cell line Colo205, HCT116 and HT29 migration by mAb, MTT method to analyze how mAb function on colon carcinoma cell line Colo205 proliferation.

RESULTS

Obtained a hybridoma cell line with continuing secretion of mouse anti-human CXCR3 mAb, named 9B5. According to rapid qualitation test paper analysis, light chain of the mAb was chain and heavy chain is IgG1 subclass. Indirect immunofluorescence and flow cytometry results show that the mAb can recognize CXCR3 molecules on the surface of activated T lymphocyte and colon carcinoma cell line Colo205, HCT116 and HT29 cell. mAb 9B5 can inhibit oriented migration of L929-huCXCR3 cells, colon carcinoma cell line Colo205, HCT116 and HT29 cell, it can also inhibit Colo205 growth promotion effect by IP-10.

CONCLUSION

Successfully obtain a hybridoma cell line with continuing secretion of mouse anti-human CXCR3 mAb, which has laid material foundation on investigation of CXCR3 expression characteristics and CXCR3 signal transduction function on tumor growth and migration. It is prospective to create a new way and a new drug for treatment of tumor metastasis.

[Construction of human CXCR3B gene transfected cell line, identification and study of its biological function]

AIM

To construct recombinant human CXCR3B gene expression vector and obtain L929-CXCR3B gene transfected cell line for stably expressing human CXCR3B.

METHODS

Human CXCR3B gene of full length was amplified by PCR from the plasmid pMD19-T/huCXCR3A. Then, it was inserted into eukaryotic expression vector pIRES2-EGFP to construct recombinant vector pIRES2-EGFP/huCXCR3B. The recombinant vector was transfected into L929 cells with Lipofectamine(TM); 2000, and cell clones stably expressing human CXCR3B molecule were screened by G418.We used FCM and RT-PCR to verify expression of CXCR3B from protein level and gene level. The ability of proliferation of L929-huCXCR3B under the circumstance of CXCR3B ligand called Mig was analyzed via MTT methods.

RESULTS

We have constructed recombinant human CXCR3B gene expression vector and obtained L929-huCXCR3B gene transfected cell line which can stably express human CXCR3B molecule. The positive expression rate of CXCR3B on L929-huCXCR3B cells was 93&. The result of MTT assay showed that the proliferation of L929-huCXCR3B cells were inhibited when the cells were cocultured with Mig after 24 h, 48 h and 72 h, and the inhibition ratio were 41.44&, 44.01& and 24.80& respectively.

CONCLUSION

Construction of L929-huCXCR3B cell line has laid a good foundation on research of the CXCR3B signal pathway and preparation of the CXCR3B monoclonal antibody.

Role of HLA-G and NCR in protection of umbilical cord blood haematopoietic stem cells from NK cell mediated cytotoxicity

Allogeneic umbilical cord blood haematopoietic stem cells (UCB-HSCs) can be transplanted into a host with the intact innate immunity with limited immuno-reaction, although the mechanisms remain unclear. The present studies aimed at investigating potential mechanisms of allogeneic UCB-HSCs escape from the cytolysis of natural killer (NK) cells. We compared UCB-HSCs ability to protect from NK-mediated cytotoxicity with peripheral blood or bone marrow haematopoietic stem cells (PB-HSCs and BM-HSCs). HSCs expressed lower levels of natural cytotoxicity receptor ligands including NKp30L, NKp44L and NKp46L than monocytes. Blocking these ligands respectively or in combination could increase the resistance of HSCs against NK cell mediated cytotoxicity. High expression of HLA-G was noticed on UCB-HSCs, rather than PB-HSCs or BM-HSCs, whereas blockade of HLA-G significantly elevated NK cell mediated cytolysis to UCB-HSCs. Thus, we conclude that natural cytotoxicity receptors and HLA-G on HSCs may contribute to the escape from NK cells, and activate and inhibitory NK cell receptors and their ligands can be novel therapeutic targets in cell transplantation.

Synergistic effects of beta-aescin and 5-fluorouracil in human hepatocellular carcinoma SMMC-7721 cells

The effects and mechanisms of action of beta-aescin and 5-fluorouracil (5-FU), alone and in combination, were studied in human hepatocellular carcinoma SMMC-7721 cells. Growth inhibition, cell cycle distribution, apoptosis, Bcl-2 expression and caspase activity were assessed. The Isobole-method/interaction-index analysis was applied to evaluate the synergy, additivity or antagonism of these agents. The results indicate that mixtures of beta-aescin and 5-FU showed a synergistic effect on the 50% inhibitory effect when their ratio was 4:1 when compared with either agent alone. The mechanism of action could be through the synergistic arrest of the cell cycle, induction of apoptosis, activation of caspases-3, 8 and 9, and down-regulation Bcl-2 expression. The results suggest that mixtures of these two agents had a synergistic inhibitory effect on SMMC-7721 cells, an observation which might be useful for the further development of anti-cancer drugs.

[Construction of murine CXCR3 gene transfected cell line, identifiction and study of its biological function]

AIM

To construct recombinant murine CXCR3 gene retroviral vector and obtain L929-mCXCR3 gene transfected cell line for stably expressing murine CXCR3. We further study on L929-mCXCR3 migration effect resulted from interaction by CXCR3 and its ligand IP-10.

METHODS

One female BALB/c mouse (7 weeks) was injected with 0.5 mg Con A intravenously (i.v.) via a tail vein. Twelve hours later the mouse was sacrificed and the spleen was removed.The spleen was pressed through a 150 microm stainless steel mesh. The isolated splenocytes were cultured in RPMI1640 supplemented with 50 U/mL human IL-2 for 3 days.Total RNA was extracted with TRIzol. Murine CXCR3 gene of full length was amplified by RT-PCR, then, it was inserted into retrovirus vector pEGZ-term. The recombinant vector together with its helper virus vector were co-transfected into package cell 293T with Lipofectamine(TM); 2000.The supernatant of 293T was collected for infecting L929 cells (repeated three times), and cell clones stably expressing murine CXCR3 molecule were screened by zeocin(500 mg/L). We used FCM and RT-PCR to verify expression of CXCR3 from protein level and gene level, respectively. Studied migration ability of L929-mCXCR3 interacted with its ligand IP-10 by transwell system.

RESULTS

We have constructed recombinant murine CXCR3 gene retroviral vector and obtained L929-mCXCR3 gene transfected cell line which can stably expressing murine CXCR3 molecule. Positive expression rate of membrane is 97.0%, and it can directly migrate induced by IP-10, the chemotatic index is 4.356%.

CONCLUSION

Construction of L929-mCXCR3 cell line has laid a good foundation on research of biologic characteristics of CXCR3 signal path , establishment of tumor metastasis model and preparation of anti-murineCXCR3 monoclonal antibody.

Therapeutic effect of MIP-1alpha-recruited dendritic cells on preestablished solid and metastatic tumors

We previously found that dendritic cell (DC) precursors could be recruited into the peripheral blood of B6 mice by administration of macrophage inflammatory protein (MIP)-1alpha. These MIP-1alpha-recruited DCs could induce anti-tumor protective immunity when pulsed with tumor cell lysate. In this study, MIP-1alpha-recruited DCs could not effectively suppress preestablished tumor when pulsed with B16 tumor cell lysate. However, inoculation with these DCs expressing MAGE-1 induced an anti-tumor immunity against preestablished solid and metastatic tumor from B16-MAGE-1 cells. These MIP-1alpha-recruited DCs expressed higher level of CCR7 and displayed a more significant chemotactic response toward secondary lymphoid tissue. Therefore, they are superior in the induction of cytotoxic T lymphocytes and the inhibition of tumor development and metastasis than bone marrow-derived DCs. This study established a novel approach to the treatment of preestablished solid and metastatic tumors using MIP-1alpha-recruited DCs transduced with tumor antigen gene.

A novel approach to induce human DCs from monocytes by triggering 4-1BBL reverse signaling

Dendritic cells (DCs) are responsible for the initiation of immune responses. Our study demonstrates a new pathway for generating a large quantity of stimulatory monocyte-derived DCs (Mo-DCs) from human monocytes using anti-4-1BB ligand (4-1BBL) mAb to trigger reverse signaling. The anti-4-1BBL-driven Mo-DCs (DCs(alpha-4-1BBL)) not only express higher levels of CD86, CD83 and HLA-DR, when compared with the Mo-DCs matured by tumor necrosis factor alpha, but also exhibit a unique phenotype that expresses lower levels of PD-L1. High levels of GM-CSF, M-CSF and Flt3 ligand (FL) were found in the anti-4-1BBL-differentiation culture. Neutralizing M-CSF, GM-CSF and FL inhibited Mo-DC proliferation stimulated by anti-4-1BBL mAb, suggesting that M-CSF, GM-CSF and FL are involved in cell proliferation stimulated by anti-4-1BBL. Further analysis of the DCs(alpha-4-1BBL) showed increased secretion of T(h)1-type cytokines IL-12 and IFN-gamma and decreased secretion of IL-10. DCs(alpha-4-1BBL) induced much stronger proliferative responses in the mixed lymphocyte reaction assay when compared with DCs derived by GM-CSF. Moreover, DCs(alpha-4-1BBL) preferentially induced T(h)1 responses. We have further demonstrated that anti-4-1BBL antibody stimulated nuclear translocation of NF-kappaB from the cytoplasm in monocytes, suggesting that reverse signaling by 4-1BBL is likely responsible for mediating DC differentiation. Collectively, we have found that reverse signaling of 4-1BBL promotes the differentiation of potent T(h)1-inducing DCs from human monocytes.

Cloning, purification and bioactivity assay of human CD28 single-chain antibody in Escherichia coli

Engineered single chain antibodies have become a powerful source of immunotherapy against a wide range of diseases. Here, we present the generation of human CD28 single-chain antibody gene (CD28-ScFv), which contained variable fragments of heavy chain and light chain (VH and VL) of the anti-CD28 antibody, and a linking peptide (Gly4Ser)3 inserted in the middle of VH and VL. The fused gene CD28-ScFv was successfully expressed in BL21 (DE3) cells and confirmed by western blotting assay. The molecular weight of CD28-ScFv was 43 kDa and the major fraction was expressed as an insoluble body. By dissolving the insoluble bodies, renaturing in vitro and purifying with a Ni-NTA affinity column, highly purified expression products of CD28-ScFv were obtained. This product could recognize and bind to CD28+ positive T cells. The proliferation capacity of peripheral blood T cells was increased by purified CD28-ScFv. In this study, we improved orthodox renaturing techniques by combining the dilution renaturation with phase gradient dialysis. With this new method, highly purified CD28-ScFv products were developed and biological activity of the products was similar to that of the mouse monoclonal anti-human CD28 antibody.

[Inhibitory and lethal effects of human-mouse chimeric antibody against CD80 on the growth of B lymphoma cell lines Raji and Daudi]

AIM

To study the inhibitory and lethal effects of human-mouse chimeric antibody against CD80 (named ch-4E5) on the growth of B lymphoma cell lines Daudi and Raji.

METHODS

Immunofluorescence and flow cytometry were used to analyze the detection of membrane CD80 in Raji and Daudi by ch-4E5. After the co-culture of ch-4E5 with Raji and Daudi, respectively, at the final concentration of 10 mg/L, the expression of Fas and FasL was observated to be at the 0 h, 4 h, 10 h, 16 h, 24 h and 48 h by direct immunofluorescence and flow cytometry, and the blocking effect on cell growth of ch-4E5 was determined at 72 h by MTT assay. MTT assay was also used to study the ADCC effect with PBMC as effector cells and Raji and Daudi as target cells. The efficiency target ratio was 20:1.

RESULTS

The combination rate between ch-4E5 and Raji and Daudi was 98.6% and 96.4%, respectively. After the co-culture of ch-4E5 with Raji and Daudi cells for 4 hs, the expression of FasL in Raji began to up-regulate. It reached the peak at 16 h and its positive rate was 16.8%. Compared with human IgG1 control group, it was increased obviously (P<0.01). The expression of Fas increased at 10 h, and then reached the top at 24 h. The combination rate was 15.6%. There was significant deviation compared with human IgG1 control group (P<0.01). Moreover, the expression of FasL and Fas on Daudi was also altered. The trend was similar to these on Raji, and the highest expression was 15.9% and 13.7%, respectively. The inhibitory rate was 34.60% and 32.64% respectively when ch-4E5 with Raji and Daudi had been co-cultured for 72 h (P<0.01). Furthermore, ch-4E5 could mediate the ADCC effect and the maximum killing rate was 55.61% and 54.42%, respectively(P<0.01).

CONCLUSION

The human-mouse chimeric antibody against CD80 can inhibit the proliferation of B lymphoma cell lines Daudi and Raji cells through Fab and Fc sections in vitro.

[Preparation of two mouse anti-human PD-1 monoclonal antibodies and identification of their biological characteristics]

AIM

To prepare mouse anti-human PD-1 monoclonal antibodies (mAbs) and identify their biological characteristics.

METHODS

The BALB/c mice were immunized with the transfected cell line PD-1/L929. The cells were fused with Sp2/0 using monoclonal antibody techniques and the positive clones were screened by FCS with PD-1/L929. The secreted anti-PD-1 mAbs were identified through rapid isotyping analysis, karyotype analysis, Western blot, competitive inhibition test, indirect immunofluorescence assay, and tumor cell lines detection.

RESULTS

Two mouse anti-human PD-1 hybridomas were obtained and their secreted mAbs were named (1F2 and 5F10). Their biological characteristics suggested that they could recognize a protein with approximate molecular weight 55 000 on PD-1/L929 cell lines and different epitopes. 1F2 could recognize PD-1 molecules expressed on SKHep-1 and 7721 while 5F10 could recognize Raji cells.

CONCLUSION

Two mouse anti-human PD-1 hybridoma cell lines and their secreted monoclonal antibodies have been successfully obtained and identified.

Therapeutic effects of anti-B7-1 antibody in an ovalbumin-induced mouse asthma model

Allergic asthma is a chronic inflammatory disorder of airways, which is characterized by attacks provoked by exposure to so-called asthma triggers, such as pet dander, second-hand tobacco smoke, dust mites, and mold spores. B7-1 (CD80), perhaps one of the most studied co-stimulatory molecules involved in asthma, plays a key role in regulating allergen-induced T cell activation in asthma, probably through T cell recruitment and Th cell differentiation upon allergen provocation. The present study was designed to test the hypothesis that anti-B7-1 antibody has therapeutic effects in asthma by blocking B7-1/CD28 pathway. The asthma model was established by ovalbumin (OVA) sensitization and challenging in female Balb/c mice. One hour after the last induction, mice were sacrificed and whole lung lavage was conducted. Cell numbers in bronchoalveolar lavage fluid (BALF) were determined and the expression levels of IFN-gamma and IL-4 in supernatant were measured by an enzyme-linked immunosorbent assay method. Sedimental cells smears were stained with Wright's-Gimsa mixed coloring method. The B7-1 expression was detected by immunohistochemistry method with frozen tissue sections. The anti-B7-1 antibody treatment could alleviate asthmatic syndromes induced by OVA. The number of recoverable eosinophils in BALF in the anti-B7-1 antibody treated group was significantly lower than that in the control group (P<0.01) and the eosinophils peribronchial infiltration was remarkably reduced in anti-B7-1 treated asthmatic mice, based on histological evaluation. The treatment with the anti-B7-1 antibody induced IFN-gamma expression and decreased IL-4 expression, compared with the asthmatic control group (P<0.01). In conclusion, the anti-B7-1 antibody approach may provide a novel therapy for allergic asthma.

[Expression of human-mouse chimeric antibody against CD40 in CHO cell line and characterization of its function]

AIM

To investigate the stable expression of a chimeric antibody against CD40 moleculeèch-5C11éin CHO and its biological activity.

METHODS

Human-mouse chimeric antibody against CD40 recombinant plasmid and mock plasmid were transfected into CHO cell line through lipofectamine mediation. Human kappa chain and Fc fragment of ch-5C11 were characterized by FACS and Western blot. The concentration of ch-5C11 in cell supernatants was detected by Lowry assay and the inhibitory effect of ch-5C11 on the proliferation of Daudi cells was detected by MTT assay.

RESULTS

RT-PCR showed that target CHO cells integrated chimeric heavy chain and chimeric light chain gene. FACS and Western blot showed that ch-5C11 in cell supernatants maintained the binding activity and specificity to human CD40 molecule, and contained human kappa chain and Fc fragment. Cell supernatants were purified using protein G affinity chromatography. The concentration of human-mouse chimeric antibody against CD40 in cell supernatants was 0.535 mg/L. When co-cultured with B lymphoma cell line Daudi, ch-5C11 induced proliferation arrest of Daudi cells.

CONCLUSION

The human-mouse chimeric antibody against CD40 can be expressed in CHO stably and effectively, which inhibits proliferation of Daudi.

Recombination of CXCR4, VEGF, and MMP-9 predicting lymph node metastasis in human breast cancer

We investigated the expression of CXC chemokine receptor 4 (CXCR4), vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)-9 to elucidate whether these markers could predict lymph node metastasis in human breast cancer. Higher rates of CXCR4 (61%), VEGF (68%), and MMP-9 (63%) expression were found in breast cancer tissues than in normal and atypical hyperplasia tissues. The expression of these markers was significantly associated with primary tumor progression, histological grade, and lymph node status. We found there were significant correlations between the expressions of any two of the three markers (P<0.001). Furthermore, our studies indicated that concomitant expression of CXCR4/VEGF (P=0.007), CXCR4/MMP-9 (P<0.001) or VEGF/MMP-9 (P=0.003) had stronger correlation with lymph node metastasis than did each alone and that combined expression of all three makers strongly correlated with lymph node metastasis (P<0.001). Thus, simultaneously examining the expression of CXCR4, VEGF, and MMP-9 in cancer tissues of breast cancer will provide valuable prognostic diagnosis of lymph node metastasis.

Blocking tumor necrosis factor-α inhibits folic acid-induced acute renal failure

Systemic administration of mice with folic acid (FA) has been used for studying the pathogenesis of acute renal failure. However, the molecular mechanisms by which FA induces acute renal failure remain poorly understood. We found that CD-1 mice treated with FA developed acute renal failure characterized by increased blood urea nitrogen, necrosis, and apoptosis of tubular epithelial cells. Compared to control mice, tumor necrosis factor-alpha (TNF-alpha) was markedly elevated in blood and kidneys of these FA-treated mice, accompanied by markedly reduced expression of anti-apoptotic protein BclxL in their kidneys. In vivo administration of FA-treated CD-1 mice with neutralizing anti-TNF-alpha antibody restored the expression of BclxL in kidneys and inhibited the necrosis and apoptosis of renal tubular epithelial cells, leading to the amelioration of acute renal failure. In ex vivo cultures, we found that FA enhanced production of TNF-alpha, decreased expression of BclxL protein, and induced apoptosis of mouse cortical tubule (MCT) cells. Addition of neutralizing anti-TNF-alpha antibody, but not control IgG, in the cultures markedly blocked the apoptotic death of FA-treated MCT cells and restored expression of BclxL to the same levels as those MCT cells cultured in the absence of FA. All these results suggest that TNF-alpha is a critical inflammatory cytokine responsible for FA-mediated acute renal failure. Furthermore, in vivo administration of anti-TNF-alpha antibody may be proved as an effective approach for acute renal failure prevention and treatment.

Comparative analysis of the effects of sample source and test methodology on the assessment of protein expression in acute myelogenous leukemia

Numerous studies have analyzed the expression and prognostic importance of various proteins in acute myelogenous leukemia (AML). We sought to determine whether the sample source and methodology used to measure protein expression affect the results obtained. To determine the importance of sample source, we used Western blotting to compare the expression of eight proteins and phosphoproteins in the leukemia blast-enriched fraction of 118 blood- and 108 marrow-derived samples, including 37 paired samples. To determine the importance of methodology, the expression of five proteins was measured in 20 paired samples by Western blotting, laser scanning cytometry (LSC), and flow cytometry. The mean expression and range of expression in blood- and marrow-derived samples were statistically identical for all eight proteins. Expression measurements for the 37 paired blood and marrow samples also had very high statistical correlation. The LSC and flow cytometry data had the highest concordance when compared using Kolmogorov-Smirnoff D-stats (range of R values, 0.8-1.0). High concordance was also observed between the LSC and flow cytometry results when the percentage of cells positive for expression was dichotomized into positive or negative expression. However, there was less correlation between LSC and flow cytometry when the actual percentages of positive cells were compared. The majority of discordant situations involved samples that were positive by flow cytometry but negative by LSC. The correlation between Western blotting signal intensity and the percentage of expression-positive cells measured by LSC or flow cytometry varied by protein but was limited when there was little heterogeneity in expression by either method. In conclusion, provided that leukemia blast-enriched fractions were analyzed, the blood- and marrow-derived samples had identical protein expression. There was good concordance of results between flow cytometry and LSC, which share similar technology, but more limited correlation between these methods and Western blotting.

Apoptosis of multiple myeloma cells induced by agonist monoclonal antibody against human CD28

CD28 is expressed abnormally on human multiple myeloma (MM) cells but the significance had not been identified until now. In this paper, we are suggesting that abnormal expression of CD28 might be a marker of tumour progression. We therefore took the approach of generating a hybridoma cell line capable of secreting agonist monoclonal antibody directed against human CD28 (agonist anti-CD28 mAb) and then determined the expression of CD28 molecules on the MM cell lines U266 and XG1. The biological effects of agonist anti-CD28 mAb on cell growth and proliferation of U266 and XG1 cell lines were then analysed. Our results showed that the expression of CD28 on U266 and XG1 was significantly higher than that of PBTC or Jurkat cells. We found that by adding the agonist anti-CD28 mAb to cultures of U266 and XG1 cells their rate of growth and proliferation was obviously inhibited. Further morphological and molecular analyses found that U266 and XG1 incubated with agonist anti-CD28 mAb showed signs of nuclear condensation, chromatin marginal changes, cells membrane breaking, and cytoplasmic shrinkage. Vacuoles and apoptotic bodies were also observed using a transmission electron microscope and the development of typical DNA laddering patterns were found by the use of electrophoresis assays, suggesting that U266 and XG1 cells were undergoing apoptosis induced by agonist anti-CD28 mAb in vitro.

Effect of acetylcholine on in vitro IL-2 production and NK cell cytotoxicity of rats

In the present study, we explored the effect of acetylcholine (ACh) on lymphocyte function and the receptor mechanisms mediating the effect. Concanavalin A (Con A)-induced interleukin-2 (IL-2) production and natural killer (NK) cell cytotoxicity were used to assess function of the T lymphocytes and the NK cells from rat spleens. Muscarinic ACh receptors (mA ChRs) agonist pilocarpine and antagonist atropine, as well as nicotinic ACh receptors (nAChRs) agonist nicotine and antagonist tubocurarine were used to determine the action pathways of ACh on T and NK cells. ACh at the concentrations of 10(-10) to 10(-8) M exerted an enhancing effect on Con A-induced IL-2 production and an inhibitory effect on NK cell cytotoxicity. Both pilocarpine and nicotine at the same doses as ACh could mimic these effects of ACh. The enhancing effect of ACh on IL-2 production could be blocked by either atropine or tubocurarine. But the inhibitory effect of ACh on NK cell cytotoxicity was abolished only by atropine, not by tubocurarine. These results suggest that ACh, which is a neurotransmitter of peripheral parasympathetic nervous system, can regulate function of T and NK cells, and the different regulatory effects of ACh on the two types of lymphocytes may be mediated by the different receptor mechanisms.

Uptake of the neutral amino acids glutamine, leucine, and serine by Pneumocystis carinii

Experiments to elucidate the mechanism by which Pneumocystis carinii transports glutamine, leucine, and serine were performed in this study. Uptake of all three radiolabeled amino acids exhibited first-order, saturation kinetics as extracellular substrate concentrations were increased, thus ruling out simple diffusion and indicating carrier-mediated transport. Kinetic analyses of amino acid uptake and the results of competitive inhibition experiments suggested that leucine, serine, and glutamine were taken up via a common transporter system. The uptake of serine was examined in greater detail to characterize the nature of the carrier. Serine uptake was not affected by N, N'-dicyclohexylcarbodiimide, carbonyl cyanide m-chlorophenyl hydrazone, ouabain, gramicidin, valinomycin, sodium azide, salicylhydroxamine acid (SHAM), iodoacetate, iodoacetate plus SHAM, KCN, and azide. Thus serine uptake did not require sodium or energy from ATP, an electrochemical proton gradient or a membrane potential across the cell surface (i.e., proton-motive force). Serine uptake was dependent on glucose in the extracellular compartment. In the presence of glucose, serine uptake was inhibited by chloramphenicol but not cycloheximide. The results from these experiments are most consistent with facilitated diffusion as the mechanism. After 30 min of incubation, most of the radioactivity was in the cellular soluble fraction. In most cases, incorporation into the extractable total lipids and the remaining particulate cellular components were detectable after this incubation period.