TABLE 1.

Binding of H. influenzae strains to Chang epithelial cells

Strain	Phenotype	Binding (CFU/well)a (% of inoculum)
Eagan	Type b, clinical isolate	3.1 × 106 ± 0.4 × 106 (11)b
H229	Eagan, OapA−	1.2 × 105 ± 0.2 × 105 (1.1)
Rd	Unencapsulated type d clinical isolate	4.1 × 106 ± 0.6 × 106 (13)b
H209	Rd, OapA−, Kanr	1.4 × 105 ± 0.2 × 105 (1.5)
H217	H209, OapA+, Kans	3.4 × 106 ± 0.4 × 106 (11.3)b
H233	Nontypeable, clinical isolate	6.0 × 106 ± 1.0 × 106 (20)b
H487	H233, Oap−, Kanr	7.9 × 105 ± 1.3 × 105 (6.5)

^aMean ± standard deviation of at least five separate experiments done in triplicate. 

^bP < 0.01 by two-tailed unpaired t test compared to the corresponding OapA mutant.