A HUMAN SP-C PROMOTER FRAGMENT TARGETS ALPHA-1-PROTEINASE INHIBITOR GENE-EXPRESSION TO LUNG ALVEOLAR TYPE-II CELLS IN TRANSGENIC MICE

A 1.277 kb promoter fragment of the gene encoding one of the lung surf actant proteins, SP-C, was cloned from a human genomic library and cha racterized using the human alpha 1-proteinase inhibitor (alpha 1PI) ge ne as reporter. Messenger RNA for human alpha 1PI isolated from a sing le transgenic mouse line was detected solely in lung tissue. Using imm unogold electron microscopy, accumulation of human alpha 1PI was shown unambiguously to occur only in type II pulmonary cells and, in discre te amounts, in the alveolar lining fluid. The protein was secreted and glycosylated showing a molecular weight close to that of plasma-deriv ed human alpha 1PI.