@article {PENNING339, author = {LOUIS C. PENNING and CHRISTINE J. PIEK and DOUG W. EIB and RAYMOND G. SCHIPPER and TJADINE M. HOLLING and GERARD J.M. MARTENS}, title = {Induction of Apoptosis in Hematopoietic Cells with an Antibody Against Tomoregulin-1}, volume = {26}, number = {1A}, pages = {339--346}, year = {2006}, publisher = {International Institute of Anticancer Research}, abstract = {Tomoregulin-1, a type-I transmembrane protein with two follistatin modules, a unique epidermal growth factor (EGF) domain and a short, highly conserved cytoplasmic tail, was studied. A number of hematopoietic cell lines (L1210, CEM, Jurkat, U937, K562, JY, THP-1 and T2) express tomoregulin-1 endogenously. In these cells, apoptosis was induced by an antiserum (C29) and purified IgG against the follistatin modules, but not by antisera against the EGF-domain or the cytoplasmic tail. Furthermore, C29 induced apoptosis in tomoregulin-1-, but not in mock-transfected cells. Apoptosis was monitored through genomic DNA fragmentation, annexin-V staining and caspase-3 activation. Treatment of the cells with C29 in the presence of H89 (a Ser/Thr kinase inhibitor) or 8'-bromo-cyclicAMP revealed that apoptosis was mediated by a cAMP-dependent Ser/Thr kinase. Moreover, C29 increased [cAMP]i over 5-fold. Together, these data suggest that the C29 antiserum against tomoregulin-1 induces apoptosis of hematopoietic cells. Copyright{\textcopyright} 2006 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved}, issn = {0250-7005}, URL = {https://ar.iiarjournals.org/content/26/1A/339}, eprint = {https://ar.iiarjournals.org/content/26/1A/339.full.pdf}, journal = {Anticancer Research} }