Aggregation of Recombinant Monoclonal Antibodies and Its Role in Potential Immunogenicity.

Background: Development of new recombinant biotechnology products has greatly expanded in the field of modern pharmacy and medicine. Since biological recombinant molecules are sensitive, simple or composed proteins, their function is heavily dependent on their structure. In addition to their efficacy, biological medicinal products could show side effects such as immunogenicity.

Ammodytoxin, a neurotoxic secreted phospholipase A(2), can act in the cytosol of the nerve cell.

Recent identification of intracellular proteins that bind ammodytoxin (calmodulin, 14-3-3 proteins, and R25) suggests that this snake venom presynaptically active phospholipase A(2) acts intracellularly. As these ammodytoxin acceptors are cytosolic and mitochondrial proteins, the toxin should be able to enter the cytosol of a target cell and remain stable there to interact with them. Using laser scanning confocal microscopy we show here that Alexa-labelled ammodytoxin entered the cytoplasm of the rat hippocampal neuron and subsequently also its nucleus.