Production of Mucous Glycoproteins by Nasal Turbinates in Vitro

Abstract

An in vitro system of human nasal turbinate tissue culture has been developed. Nasal turbinate tissue resected during surgery for nasal obstruction is dissected free of bone, placed on absorbable gelatin sponges, and cultured with CMRL-1066 medium containing antibiotics. Viability of explants may be demonstrated both physiologically and histologically through a period of 4 weeks. 3H-glucosamine added to the medium is biosynthetically incorporated into mucous glycoprotein (MGP). Gel filtration column chromatography on Sephacryl S-1000 in 6M urea in 0.005M phosphate buffer demonstrates human turbinate MGP to fractionate with 85% of the radiolabel filtered and 15% excluded by the column. The excluded MGP fractionates with globular proteins of >20 × 106 daltons, while the fractions that enter the column filter with molecular sizes of 0.4 × 106 to 20 × 106 daltons. MGP synthesized by human lung airways has comparable sizing characteristics, suggesting a similarity in upper and lower airway mucus chemistry.