Diversity of the peptide moiety of human airway mucins

A lambda gt11 cDNA library constructed from human tracheal mucosa was screened with rabbit antibodies raised to chemically deglycosylated pronase glycopeptides from bronchial mucins. This library allowed us to select 20 positive clones. The total or partial nucleotide sequences of 14 of them were classified in three different types of organization or families. Antibodies purified from total immuneserum on each positive clone were specific either of goblet cells or goblet cells and mucous cells, showing a differential cellular expression of the peptide axis of mucins. The use of each type of nucleic probe in Northern blot analysis confirmed the existence of a great heterogeneity of the RNAs contributing to a great peptide heterogeneity.