Role of Apoptosis in Rabies Viral Encephalitis: A Comparative Study in Mice, Canine, and Human Brain with a Review of Literature

Table 2

Pathological features in mouse brain following inoculation with different strains of rabies virus with different routes of inoculation.

Virus type and route of inoculation		Histological features			Rabies viral antigen	Pattern of deposition
		PVI	Microglial response	Negri bodies
CVS intracerebral	Suckling mice (Age: 0–2 days)	0–+	0–+	—	Widespread but specific localization to ventral thalamus, hypothalamus, hippocampus, limbic structures- cingulate, amygdala, and brain stem	Diffuse labeling, cytoplasmic vacuolation, minimal dendritic spread; No Negri bodies
	Weanling mice (Age: 21 days)	+	+	—		Same
	Adult mice (Age: 3 months)	+	+	—		Same
CVS intramuscular	Suckling mice (Age: 0–2 days)	Not done	ND	ND	ND	ND
	Weanling mice (Age: 21 days)	+	+	—	Specific localization to ventral thalamus, hypothalamus, hippocampus, brain stem	Diffuse cytoplasmic labeling, extensive vacuolation, minimal dendritic spread; No Negri bodies
	Adult mice (Age: 3 months)	+	+	—	Same	Same
Street intracerebral	Suckling mice (Age: 0–2 days)	++	++	+	More widespread	Multiple Negri body like intraneuronal aggregates, dendritic spread ++
	Weanling mice (Age: 21 days)	++	++	+	High density in thalamus, hypothalamus, hippocampus and limbic areas, brain stem, moderate in cortex, basal ganglia	Same
	Adult mice (Age: 3 months)	++	++	+		Same
Street intramuscular	Suckling mice (Age: 0–2 days)	Not done	NA	NA	NA	NA
	Weanling mice (Age: 21 days)	++	++	+	Widespread, caudocranial gradient	Intraneuronal aggregates, dendritic spread ++
	Adult mice (Age: 3 months)	++	++	+	Same	Same

Abbreviations used: PVI: perivascular inflammation, ND: not done, NA: not available.