I asked the doctor this morning about Adam’s (mostly) lack of reactions to all things antibody. I should have done it before, but better late than never.
They take LOTS of blood as part of this trial each Monday, Wednesday and Friday. One of the tests they do is to take a serum sample, and see how it reacts to neuroblastoma cells in their lab. If there is no reaction this would be indicative of Adam’s body producing an immune reaction to the ch14.18 antibody itself. Known as a Human Anti-Chimeric Antibody (HACA) response, this is where the body produces it’s own antibodies to neutralize the intravenously delivered 14.18 antibodies, stopping them doing their job i.e. attaching to GD2 receptors on neuroblastoma cells. It also stops them causing pain by attaching to receptors on normal nerve cell endings. It’s a common reaction/problem in mouse-derived antibodies (HAMA response), but much less so in chimeric antibodies (which are part murine, part human). It is the reason why chimeric 14.18 is used rather than antibodies of a solely murine origin.
The upshot is the doctors know that the ch14.18 antibodies in Adam’s blood serum are reacting to neuroblastoma cells.
And the moral of this story is; if in doubt …