TABLE 3.

Protection against NTHi infection mediated by immunization of chinchillas with strain 12 HMW1/HMW2 and OMV preparations

Expt no.	Immunogen	No. of animals		Titerc
		Challenged	Infected
1	Freund's	3	3a	<1:10
	Strain 12 HMW	3	2	<1:10
	Strain 12 OMV	3	0a	≥1:320
	Strain 12 OMV + strain 12 HMW	3	0a	≥1:320
2	Freund's	4	4b	<1:10
	Strain 12 OMV	4	0b	≥1:320
	Strain 12 OMV + strain 12 HMW	4	0b	≥1:320

^aP = 0.014, Fisher exact test.

^bP = 0.002, Fisher exact test.

^cOpsonophagocytic titer versus HMW1/HMW2 downregulated strain 12.