. 2016 May 26;11(5):e0156255. doi: 10.1371/journal.pone.0156255

Table 1. Summary of studies concerning biology of tissue cysts in rodents.

Rodent					Toxoplasma gondii				Cyst biology		References
Host	Strain	Sex	Age	N=	Strain genotype	Route	Dose	Duration	Distribution	Method
Rat	Long-Evans	M	8 w	6	II, Prugniaud^a	i.p.	1 million tachyzoites		More cysts in amygdalar region	Histology-data pooled, bioluminescence	[21]
Rat	Wistar	M	NS	28	I, RH^b	i.p	100 or 1000 tachyzoites	25 days	Mid brainedial portion	Histology, HE, PAS, coronal sections	[22]
Rat	Wistar	M	NS	28	I, RH^b	i.p	1000 or 1500 tachyzoites	49 days	Mid brain	Histology, HE, PAS, coronal sections-10 rats	[22]
Mice	BALB/c	F	7 w	6	II, Prugniaud^a	i.p.	400 tachyzoites		More cysts in amygdalar region	Histology-data pooled, bioluminescence	[21]
Mice	CD, Outbred	M	mo	5	NS, HIF^c	oral	10 tissue cysts	18 weeks	No preference	Coronal sections, histology, HE, 1600 sections per mouse	[23]
Mice	C57BL/6J	F	7 w	19	II, ME49^d	i.p.	100, 1000, 100,000	9 weeks^e	No tropism	Coronal sections-40 μm, fluorescence microscopy	[24]
Mice	C57BL/69H-2^b)	NS	10–12 w	6–14	II, ME49^d	i.p.	20 tissue cysts	3 weeks, 6 weeks	At 3 weeks, tissue cysts more in hippocampus, same trend at 6 weeks but results not conclusive	tissue cysts counted in homogenate of brain	[25]
Mice	Swiss webster	F	NS	4	II, ME49^d	i.p.	10 tissue cysts	6 months NS		Homogenate of brain, 20μl tested, 213 tissue cysts measured	[26]
Mice	STR, outbred	NS	2 mo	65	SRA	s.c.	12 tissue cysts	7 days-22 mo	Pathogenesis described. cyst rupture not observed^f	HE, TEM, IHC	[27]

^a Strain isolated in 1964 from human fetus, genetically modified to express firefly luciferase and green fluorescent protein.

^b Strain isolated in 1937 from the brain of a child. It can no longer induce oocyst formation in cats and some lines of this parasite disappear in animals 21 days p.i.

^c Isolated in 1993 from the brain of a HIV-positive patient.

^d Isolated in 1950’s from diaphragm of sheep. Genetically modified to express green fluorescent protein.

^e 14.3%-mortality-10,000; 19.2%-mortality 100,000.

^f Of 32 mice studied 1–22 mo p.i., few contained glial nodules with immunoreactive debris/organisms but most nodules did not contain T. gondii. There was no evidence for new tissue cyst formation.

M = Male, F = Female, N = Number, NS = Not stated, w = Week, mo = Month, i.p. = Intra peritoneal, HE = Hematoxylin and Eosin. PAS = Periodic Acid-Schiff reagent.