sentence: This contrasts to the 10 kDa dextran in which the fluorescence intensity was equivalent in both the hemolymph and tracheal lumen 10 min after injection.2 Though the leakage of the 70 kDa marker into the tracheal lumen is less than with the 10 kDa marker , the presence of 70 kDa dextran in the tracheal lumen of cora and wun wun2 mutants leads us to conclude that loss of SJ function causes permeability to 70 kDa molecules.If the Serp and Verm can leak out of wun and SJ mutant trachea , this raises the question of why the 2A12 antigen remains in the tracheal lumen .