Table 5. Results of specificity of immunohistochemistry based neutralization test.

Sample #	Pretreatment conditions		Observed titer        (IU/mL)	Fold change in titer              (IU/mL)§*
142/11	Homologous Competitor (Inactivated Rabies Pitman Moore Strain)	1:2 Diluted   Media Control	8.9	N/A
		1:2 Diluted     Competitor	<0.1	(–) 178.0
		1:4 Diluted     Competitor	0.5	(–) 17.8
		1:8 Diluted     Competitor	2.0	(–) 4.5
	Heterologous Competitor (Inactivated Measles Virus)	1:2 Diluted   Media Control	10.0	N/A
		1:2 Diluted     Competitor	10.3	(+) 1.3
		1:4 Diluted     Competitor	11.4	(+) 1.4
		1:8 Diluted     Competitor	8.9	(–) 1.1

HRIG was treated with either increasing concentrations of rabies vaccine or inactivated measles virus and RVNA titers tested. There is a marked decrease in titers after treating with homologous inhibitor compared with heterologous inhibitor.