Antibody-drug conjugates(ADCs)are commonly heterogeneous and require extensive assessment of exposure-efficacy and exposure-safety relationships in preclinical and clinical studies.In this study,we report the generation of a monoclonal antibody against monomethyl auristatin E(MMAE)and the development,validation,and application of sensitive and high-throughput enzyme-linked immunosor-bent assays(ELISA)to measure the concentrations of MMAE-conjugated ADCs and total antibodies(tAb,antibodies in ADC plus unconjugated antibodies)in cynomolgus monkey sera.These assays were suc-cessfully applied to in vitro plasma stability and pharmacokinetic(PK)studies of SMADC001,an MMAE-conjugated ADC against trophoblast cell surface antigen 2(TROP-2).The plasma stability of SMADC001 was better than that of similar ADCs coupled with PEG4-Val-Cit,Lys(m-dPEG24)-Cit,and Val-Cit linkers.The developed ELISA methods for the calibration standards of ADC and tAb revealed a correlation be-tween serum concentrations and the OD450 values,with R2 at 1.000,and the dynamic range was 0.3-35.0 ng/mL and 0.2-22.0 ng/mL,respectively;the intra-and inter-assay accuracy bias％ranged from-12.2％to-5.2％,precision ranged from-12.4％to-1.4％,and the relative standard deviation(RSD)was less than 6.6％and 8.7％,respectively.The total error was less than 20.4％.The development and validation steps of these two assays met the acceptance criteria for all addressed validation parameters,which suggested that these can be applied to quantify MMAE-conjugated ADCs,as well as in PK studies.Furthermore,these assays can be easily adopted for development of other similar immunoassays.

Objective To explore the role of nuclear translational factor homeobox A13(HOXA13)gene in epithelial - to - mesenchymal transition(EMT)induced by human serum albumin(HSA)overload in human renal tu-bular epithelial(HKC)cells. Methods HKC cells were treated with different concentrations of HSA(ranging from 0 - 30 g/ L)for 48 h or 20 g/ L HSA for different times(ranging from 0 - 72 h)in vitro. The protein expressions of cy-tokeratin(CK),Vimentin,and HOXA13 protein in HKC cells were detected by using Western blot respectively. Mean-while,liposome - mediated DNA transfection was used to transfect the HOXA13 gene into HKC cells before HSA treat-ment,and the expressions of CK,Vimentin and HOXA13 protein in HKC cells were also detected by using Western blot. Results (1)The protein expression of CK decreased but Vimentin increased after HKC cells were exposed to HSA,which was in a concentration - and time - dependent manner.(2)Expression of HOXA13 was down - regulated by HSA in a dose - and time - dependent manner,and the expressions of HOXA13 protein in HKC in 5 g/ L,10 g/ L, 20 g/ L,30 g/ L group were 58. 24%(P = 0. 005),44. 73%(P = 0. 003),38. 40%(P = 0. 033)and 24. 83%(P =0. 011)respectively as compared with 0 g/ L group. Likewise,the protein expressions of HOXA13 in 24 h,48 h,72 h group were 52. 00%(P = 0. 023),46. 83%(P = 0. 008)and 35. 10%(P = 0. 034)respectively as compared with 0 h group.(3)There was a positive correlation between the levels of HOXA13 protein expression and CK protein expression (r = 0. 86,P = 0. 005),while the relationship between the levels of HOXA13 protein expression and Vimentin protein expression was negative(r = - 0. 94,P = 0. 002).(4)Up - regulated expression of HOXA13 in HKC cells by lipo-fectamine transfection alleviated the degree of EMT induced by HSA significantly. The expression of Vimentin decreased by 35. 34%(P = 0. 005)while the expression of CK increased 360. 00% - fold(P = 0. 005),compared with that of untransfected HKC cells. Conclusion EMT induced by HSA in HKC cells may play a role through HOXA13.

Nitrogen removal techniques based on Anammox process are developing rapidly these years. The distribution and diversity of Anammox have become important research directions. A variety of Anammox have been detected till now, of which only Kuenenia and Brocadia are often detected in wastewater treatment systems. In addition, in a single niche there is only one type of Anammox bacteria. However, the distribution mechanism and transformation of Anammox bacteria in different niches are still ambiguous. Therefore, the distribution of Anammox in various conditions was summarized and analyzed in this article. And the key factors influencing the distribution of Anammox were concluded, including substrate concentration and the specific growth rate, sludge properties and microbial niche, the joint action and influence of multiple factors. The engineering significance research on the distribution and influencing factors of Anammox bacteria in the sewage system and proposed research prospects were expounded.
Ammonia ; chemistry ; Anaerobiosis ; Bacteria ; Nitrogen ; chemistry ; RNA, Ribosomal, 16S ; Sewage ; microbiology ; Waste Disposal, Fluid ; Waste Water