- A single amino acid change, A91V, leads to conformational changes that can impair processing to the active form of perforin. Trambas, C., Gallo, F., Pende, D., Marcenaro, S., Moretta, L., De Fusco, C., Santoro, A., Notarangelo, L., Arico, M., Griffiths, G.M. Blood (2005)









