Cynomolgus Monkey Dermal Fibroblasts

Generation and Characterization of cynHLCs from Cynomolgus Monkey Dermal Fibroblasts

This study presents the development of a Pc in vitro infection model using stem cell-derived hepatocytes from Macaca fascicularis. Cynomolgus iPS (cynIPS) cells were generated from two Cynomolgus Monkey dermal fibroblasts by reprogramming, using Sendai viruses bearing the transcription factors Oct3/4, Sox2, Klf4, and c-Myc. Pluripotent colonies appeared two to three weeks after infection and were kept on irradiated mouse embryonic fibroblasts. After several passages, the iPS cells were transferred on Matrigel, but spontaneous differentiation occurred on this feeder-less system (Fig. 1). Further investigations showed that a higher concentration of bFGF (basic fibroblast growth factor) was essential to maintain pluripotency (Fig. 1). Following the clonal expansion phase, clones exhibiting typical human embryonic stem cell-like morphology (flat and tightly packed colonies of round cells with large nuclei) were selected and characterized by immunofluorescence (Fig. 1). Based on this result the best clone (#13) was selected and checked for karyotype (Fig. 1), and differentiation potential into the three germ layers (Fig. 1).

Fig. 1. Generation and characterization of cynHLCs (Pellisson M, Zeeman A M, et al., 2021).

CERV1 Infectivity in Human and Primate Cell Lines

Endogenous retroviruses (ERVs) are ancient viral sequences in the mammalian genome, providing insights into virus–host co-evolution. Chimpanzee endogenous retrovirus 1 (CERV1), an extinct gamma retrovirus, has circulated in primates for about 10 million years. AbuEed et al. aim to understand how CERV1 was transmitted and endogenized in primates.

In the present study, CERV1 was found to be a viral interference group of PERV-A and PERV-A/C. As CERV1, PERV-A, and PERV-A/C utilize the same receptor, human and primate cell lines were assessed for susceptibility by Env-pseudotyped viruses (Fig. 2). CERV1 was found to infect humans (293T, HeLa, HT1080, and Hs68 cells), chimpanzees (Chimp-0363M cells), and African green monkeys (Cos7 and Vero cells), although not NCMDF (normal cynomolgus monkey dermal fibroblasts). Contrastingly, PERV-A was found to infect HEK293T and HeLa cells but not other lines. Moreover, with the exception of Vero cells, PERV-A/C was established to show infectivity in the human and primate cell lines assessed in this study. These findings indicate that despite using the same viral receptor, there are differences in susceptibility with respect to viral cell entry.

Fig. 2. Comparison of the infectivity of CERV1, PERV-A, and PERV-A/C in human and primate cell lines (AbuEed L, Miyake A, et al., 2025).