Isolation, genotyping and virulence determination of aToxoplasma gondiistrain from non‐human primate from China

Abstract

Toxoplasma gondii infects almost all warm‐blooded animals, including humans and non‐human primates. Many cases of T. gondii infection in non‐human primates have been reported worldwide. In this study, 15 monkeys were collected from zoos in Henan Province between 2016 and 2019. A modified agglutination test (MAT) (cut‐off: 1:8) showed that 46.7% (7/15) of the heart juices had T. gondii IgG antibody transformation. One viable T. gondii strain was successfully isolated from the myocardium of a rhesus monkey by bioassay in mice. This strain was designated as TgMonkeyCHn1. The DNA of T. gondii tachyzoites was obtained using cell cultures, and the genotype of this strain was determined by PCR‐RFLP with 10 markers and the virulence genes ROP5 and ROP18. The genotype and ROP18/ROP5 (3/6) of TgMonkeyCHn1 did not match any known genotypes. In addition, the TgMonkeyCHn1 formed low number of tissue cysts and was non‐lethal to mice. To our knowledge, this is the first T. gondii strain isolated from Old World monkeys. Rhesus monkey is a new host record for T. gondii.

Low Prevalence of Toxoplasma gondii in Sheep and Isolation of a Viable Strain from Edible Mutton from Central China

“…More importantly, we found that TgSheepCHn14 was smaller than other strains (RH, Me49, VEG, TgMonkeyCHn1, and TgRooCHn4), and it was deficient in amylopectin granules [ 2 , 38 , 49 ]. It took a long time to grow in vitro and was difficult to propagate in cell culture.…”

Isolation and Genetic Characterization of Toxoplasma gondii from a Patas Monkey (Erythrocebus patas) in China

“…MAT has been widely used to detect anti- T. gondii IgG antibodies in serum or body fluids of animals and its effectiveness has been demonstrated with T. gondii isolated from pigs, lambs, chickens, and monkeys [ 34 , 35 , 36 , 37 ]. However, the validity of MAT in NHPs remains unclear.…”

“…However, the validity of MAT in NHPs remains unclear. Previous studies using MAT at 1:16 and 1:20 dilutions have detected toxoplasmosis or isolated viable T. gondii strains in monkeys [ 31 , 32 , 37 ]. Here, a viable T. gondii strain was isolated from the striated muscles of case#21 (patas monkey), with a T. gondii antibody titer of 1:3200, and T. gondii infection was also confirmed by PCR detection in tissues (spleen, lung, kidney, and mesenteric lymph nodes).…”

“…The virulence phenotype was supported by mouse infection (low cyst formation rate and avirulence). The ROP18/ROP5 type of TgMonkeyCHn1 (3/6) has also been confirmed to be non-lethal in Swiss mice [ 37 ].…”