TABLE 3.

Histochemical labeling of young (6-week-old) and adult rabbit tracheae^a

Antibody or virus	Labeling intensity for:
	Adult trachea	Young trachea
Anti-A	++++	−
Anti-H	+++	+
UEA-I	++++	++
RHDV	++++	+
VLPs	+++	±
RHDV + UEA-I	±	ND
VLP + H type 2	±	ND
VLP + Lex	++++	ND

^aIntensity of labeling was scored from very strong (++++) to completely negative (−). ±, weak labeling. Binding of the anti-A and anti-H MAbs was revealed using a biotin–avidin-peroxidase method. Binding of UEA-I was revealed using a peroxidase-labeled lectin. Binding of RHDV and VLPs was revealed using the anti-VP60 MAb (10C5) and the biotin–avidin-peroxidase method. Inhibition of RHDV binding was tested by coincubation with unlabeled UEA-I lectin at 40 μg/ml. Inhibition of VLPs binding was tested by coincubation with polyacrylamide-conjugated H type 2 and Le^x trisaccharides at 50 μg/ml. ND, not determined.