This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'Memory cell in immune system are long lived and escape apoptosis because of: \nSelect and explain. \nA. Insulin like growth factor, B. Fibroblast growth factor (FGF), C. Platelet derived growth factor, D. Nerve growth factor', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Nerve growth factorNerve growth factor inhibits apoptosis in memory B cellsQ inactivation of p38 MAPK, prevention of antiapoptotic factor Bcl-2 phosphorylation (i.e. maintaining its integrity) & cytochrome c releaseAlthough other growth factors like FGF, PDGF and IGF can also prolong the survival, it is the nerve growth factor that is most impoant in immoalization of memory cells.Growth factor --> activate P13 kinase --> activate Akt --> inactivates procaspase 9 & inhibit Fast synthesis', 'role': 'assistant'}]