- Expression of the anaphylatoxin receptors C3aR and C5aR is increased in fatal asthma. Fregonese, L., Swan, F.J., van Schadewijk, A., Dolhnikoff, M., Santos, M.A., Daha, M.R., Stolk, J., Tschernig, T., Sterk, P.J., Hiemstra, P.S., Rabe, K.F., Mauad, T. J. Allergy Clin. Immunol. (2005)