THE DETECTION OF THE MESSENGER-RNAS OF PROCOLLAGEN TYPE-I, TYPE-II AND TYPE-III IN HUMAN FETAL FINGERS BY IN-SITU HYBRIDIZATION USING DIGOXIGENIN-LABELED OLIGONUCLEOTIDE PROBES

Messenger RNAs (mRNAs) encoding procollagen alpha 1 type I, alpha 1 ty pe II and alpha 1 type III have been localized in paraffin sections of human fetal fingers using digoxigenin-labelled synthetic oligonucleot ide probes. The probe-mRNA hybrids were visualized using an anti-digox in antibody amplified with sandwich techniques. These protocols provid ed an excellent hybridization signal with minimal background noise. Th e sensitivity of the protocols was nearly equivalent to that seen when using isotopic cDNA probes. In human fetal fingers, intense hybridiza tion signals for procollagen alpha 1 type I mRNA were detected in the osteoblasts and the fibroblasts of periosteum and perichondrium, the t enocytes of tendons, fibroblasts of ligaments, the synovial membrane a nd deeper layers of the dermis. In contrast, positive hybridization si gnals for procollagen alpha 1 type II mRNA were visualized in chondroc ytes and the cambial layer of perichondrium. The signals for procollag en alpha 1 type III mRNA were detected in the fibroblasts of the dermi s and perichondrium. The probes which have lower melting temperatures (Tm) could not detect the corresponding mRNAs.