The international standard method for the determination of trypsin inhibitor activity (TIA) in soya products, ISO 14902, was compared with the American Association of Cereal Chemists’ standard AACC 22‐40.01 as modified by Hamerstrand in 1981 (AACC‐based method), using soybean meals as matrices. TIA, expressed as milligram of inhibited trypsin per gram of sample, was determined by both methods in each of 30 samples of soybean meal. TIA values according to ISO 14902 were significantly lower (P < 0.001) than those afforded by the AACC‐based method. This difference, which means that AACC‐based method and ISO 14902 TIA values are not directly comparable, is attributable to between methods differences, in decreasing order of influence: particle size (P < 0.01), trypsin inhibitor extraction method (P < 0.05), and trypsin substrate (P < 0.01). N‐benzoyl‐l‐arginine‐4‐nitroanilide hydrochloride, the ISO 14902 trypsin substrate, affords TIA values 6.4 % higher than the racemic mixture used by the AACC method, but it seems unlikely that in most contexts this advantage would outweigh the disadvantage of its greater cost.
The protein-free medium TurboDoma HP.1 (THP.1) was used to produce the CB.Hep-1 monoclonal antibody (mAb) in a CP-1000 hollow fiber bioreactor (HFB). This mAb is used for the immunopurification of recombinant hepatitis B surface antigen (rHBsAg), which is included in a vaccine preparation against the Hepatitis B Virus. By using the experimental conditions tested in this work we were able to generate more than 433 mg of IgG in 43 days. The maximum antibody concentration obtained was about 2.4 mg ml(-1)and the IgG production per day was approximately 11 mg of monoclonal antibody, which constitutes a good concentration value in comparison to the results obtained in ascitic fluid, where concentration for this hybridoma was around 3 mg ml(-1). We used different analytical methods to control the quality of mAbs, obtained from the in vitro system. They included affinity constant determination, analysis of N-glycan structures, immunoaffinity chromatography and antigen binding properties. The results obtained suggest that no significant changes occurred in the mean characteristics of the mAb harvested from the bioreactor during the 43 days of cultivation.
The protein-free medium TurboDoma HP.1 (THP.1) was used to produce the CB.Hep-1 monoclonal antibody (mAb) in a CP-1000 hollow fiber bioreactor (HFB). This mAb is used for the immunopurification of recombinant hepatitis B surface antigen (rHBsAg), which is included in a vaccine preparation against the Hepatitis B Virus. By using the experimental conditions tested in this work we were able to generate more than 433 mg of IgG in 43 days. The maximum antibody concentration obtained was about 2.4 mg ml −1 and the IgG production per day was approximately 11 mg of monoclonal antibody, which constitutes a good concentration value in comparison to the results obtained in ascitic fluid, where concentration for this hybridoma was around 3 mg ml −1. We used different analytical methods to control the quality of mAbs, obtained from the in vitro system. They included affinity constant determination, analysis of N-glycan structures, immunoaffinity chromatography and antigen binding properties. The results obtained suggest that no significant changes occurred in the mean characteristics of the mAb harvested from the bioreactor during the 43 days of cultivation.
Soluble major histocompatibility complex class I molecules (sHLA) present in human serum can be resolved by gel filtration into two different peaks with an apparent molecular mass of about 200 kDa (30% of the total) and 50-60 kDa (60%-70%). The serological analysis of the peaks shows that A or B specificities can only be detected in the 200 kDa peak while both are recognized by the monomorphic W6/32 monoclonal antibody (mAb) and anti-beta 2-microglobulin mAb. Such sHLA (non HLA-A or -B) molecules are released from human spleen membranes upon incubation at 37 degrees C and have been purified by affinity chromatography with mAb W6/32 bound to Sepharose. The molecular mass analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the sHLA (non HLA-A or -B) and of the classical HLA-A or -B antigens still bound to the membranes and purified from the same membranes after detergent solubilization does not show a significant difference, indicating that sHLA do not represent proteolytic fragments of the classical HLA-A or -B antigens. The presence of sHLA (non HLA-A or -B) has also been detected in the supernatants of lymphocyte cultures and increases dramatically upon stimulation by mitogens. The effect of pokeweed mitogen, phytohemagglutinin, Staphylococcus aureus Cowan strain and phorbol 12-myristate 13-acetate on the secretion of sHLA has been studied. The molecular mass of the secreted sHLA (detected using [14C]leucine) is compared with the classical transmembrane proteins.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.