Production and Characterization of F(Ab') Fragments Obtained by Enzymatic Digestion from Murine Anti-MRSA PBP2a Monoclonal Antibodies.

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are a worldwide health problem. In a previous study, a murine monoclonal antibody (mMAB), capable of binding to PBP2a within MRSA strains, was generated. F(ab') antibody fragments are widely described in the literature as immunochemical tools and reagents for diagnostics and therapeutics, particularly because of their low immunogenicity and rapid pharmacokinetics.

Effects of passage number on growth and productivity of hybridoma secreting MRSA anti-PBP2a monoclonal antibodies.

Monoclonal antibodies (mAb) are high added value glycoproteins recommended for immunotherapy, diagnosis, and also for the treatment of bacterial infections resistant to multiple drugs such as Methicillin Resistant Staphylococcus aureus (MRSA). In addition to environmental conditions related to cell cultures, the intrinsic characteristics of hybridoma cells, like the secretion stability of monoclonal antibodies by the cells through successive subcultures, are relevant for the characterization of cell lines related to the productivity of mAb. The rate of mAb production differs significantly between different cell lines and different passage numbers, and it is an important variable in characterization of cell lines.

Improved replication of the baculovirus Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV) in vitro using proteins from Lonomia obliqua hemolymph.

The baculovirus Anticarsia gemmatalis nucleopolyhedrovirus (AgMNPV), a member of the family Baculoviridae, has been widely applied as a biopesticide for the control of the velvetbean caterpillar, a pest of soybean crop field. Baculoviruses are considered safe and efficient agents for this purpose, because they do not infect vertebrates, being safe for the health of humans and animals, as well as to the environment. The objective of this work was to identify proteins obtained from Lonomia obliqua hemolymph with potential application in the optimization of baculovirus AgMNPV replication in Sf9 insect cell culture.

Improved bioprocess with CHO-hTSH cells on higher microcarrier concentration provides higher overall biomass and productivity for rhTSH.

Since the recombinant thyroid-stimulating hormone (rhTSH) is secreted by stably transfected Chinese hamster ovary (CHO-hTSH) cells, a bioprocess consisting of immobilizing the cells on a substrate allowing their multiplication is very suitable for rhTSH recovering from supernatants at relative high degree of purity. In addition, such a system has also the advantage of easily allowing delicate manipulations of culture medium replacement. In the present study, we show the development of a laboratory scale bioprocess protocol of CHO-hTSH cell cultures on cytodex microcarriers (MCs) in a 1 L bioreactor, for the preparation of rhTSH batches in view of structure/function studies.

Enhancing effect of a protein from Lonomia obliqua hemolymph on recombinant protein production.

Gene expression in animal cells allows large scale production of proteins used for either structure and function studies or therapeutic purposes. Maximizing recombinant protein production is necessary to optimize cell growth and protein expression. Some studies have demonstrated the presence of pharmacologically active substances in insect hemolymph.