Production of Recombinant Allergen Proder P 1 by CHO Cells Adapted to Grow in Serum-Free Suspension

Abstract

Der p 1 is a major allergen from Dermatophagoides pteronyssinus which plays a prominent role in IgE-mediated immediate hypersensitivity reactions including asthma. We successfully expressed a recombinant precursor form of Der p 1, recProDer p 1_A [1], secreted by anchorage-dependent CHO cells cultured in cell factories. To increase the ProDer p 1 expression level and purification yield, a recombinant CHO-K1 clone was adapted [2] to growth in serum-free suspension culture. Our results showed that suspension batch cultures of the adapted CHO-K1 cell line (4846-6) in a controlled stirred tank bioreactor allow high-level expression of recProDer p 1_S. Purified allergen recProDer p 1_S was comparable to recProDer p 1_A in terms of glycosylation, enzymatic activity and IgE-reactivity. The monitoring of the consumption of nutrients and production of metabolites during batch cultures allowed establishing models capable of simulating the kinetics of mammalian cell culture.