TABLE 3.

Bactericidal titers of adult human sera after absorption with three M. catarrhalis outer membrane proteins^a

Absorbent	Bactericidal titer to the O35E strain in serum:						Bactericidal titer to the 1230-359 strain in serum:
	1	2	3	4	5	6	1	2	3	4	5	6
Noneb	450	1,350	450	50	150	450	450	4,050	1,350	150	150	450
UspA1	<50	<50	<50	<50	<50	<50	50	150	<50	<50	50	150
UspA2	<50	150	<50	<50	<50	<50	150	1,350	450	<50	50	50
74-kDa protein	450	1,350	450	50	50	150	450	4,050	1,350	150	150	450

^aSera are those described in Table 2. The bactericidal titers to both the O35E and 1230-359 strains were determined with threefold dilutions of the sera starting at 1:50. The purified UspA1 and UspA2 proteins were prepared from the O35E strain. 

^bSaline was added to samples in place of purified protein (at an equivalent volume), and samples were treated the same thereafter.