Transcriptional profiling of apoptotic pathways in batch and fed-batch CHO cell cultures.
Chinese Hamster ovary (CHO) cells are regarded as one of the "work-horses" for complex biotherapeutics production. In these processes, loss in culture viability occurs primarily via apoptosis, a genetically controlled form of cellular suicide. Using our "in-house" developed CHO cDNA array and a mouse oligonucleotide array for time profile expression analysis of batch and fed-batch CHO cell cultures, the genetic circuitry that regulates and executes apoptosis induction were examined. During periods of high viability, most pro-apoptotic genes were down-regulated but upon loss in viability, several early pro-apoptotic signaling genes were up-regulated. At later stages of viability loss, we detected late pro-apoptotic effector genes such as caspases and DNases being up-regulated. This sequential regulation of apoptotic genes showed that DNA microarrays could be used as a tool to study apoptosis. We found that in batch and fed-batch cultures, apoptosis signaling occurred primarily via death receptor- and mitochondria-mediated signaling pathways rather than endoplasmic reticulum-mediated signaling. These insights provide a greater understanding of the regulatory circuitry of apoptosis during cell culture and allow for subsequent targeting of relevant apoptosis signaling genes to prolong cell culture.
Bioprocessing Technology Institute, Biomedical Sciences Institutes, Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, no. 06-01, Centros, Singapore 138668.
Danny Chee Furng
DC
Wong
Kathy Tin Kam
KT
Wong
Yih Yean
YY
Lee
Peter Nissom
PN
Morin
Chew Kiat
CK
Heng
Miranda Gek Sim
MG
Yap
D000818:Animals; D017209:Apoptosis / Q000235:genetics* / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D016466:CHO Cells; D018929:Cell Culture Techniques / Q000379:methods; D006224:Cricetinae; D003470:Culture Media; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D020411:Oligonucleotide Array Sequence Analysis; D014158:Transcription, Genetic
D051017:Apoptosis Regulatory Proteins; D003470:Culture Media