Chlorogenic acid and insulin–transferrin–selenium supplementation during in vitro maturation enhances the developmental competence of interspecies chimera blastocysts following cell injection

Figures & data

Figure 1. Representative images of porcine blastocysts following injection of mouse induced pluripotent stem (iPS) cells: (A) blastocyst before cell injection; (B) shrunk blastocyst immediately after cell injection; (C) re-expanded blastocyst 24 h after culture; (D) hatched blastocyst 24 h after culture. Green colour represents injected iPS cells. Scale bar indicates 50 μm.

Figure 2. Effects of chlorogenic acid (CGA) and ITS supplementation during in vitro maturation on the proportions of oocytes reaching metaphase II (A) and oocytes with DNA fragmented nuclei (B), total fertilization (C), monospermic fertilization (D), blastocyst formation (E) and the total cell number of blastocysts (F). Oocytes matured in the maturation medium containing β-mercaptoethanol but not CGA and ITS served as the control group. All oocytes matured with or without CGA and ITS were used to estimate the proportions of oocytes reaching metaphase II (MII) and having nuclei with fragmented DNA (146–152 oocytes per treatment), and of fertilization (139–152 oocytes per treatment) and embryo development (199–230 oocytes per treatment). All the experiments were repeated four to five times. Each bar represents the mean value ± SEM. Bars with different letters differ significantly (P < 0.05).

Table 1. Effects of CGA and ITS supplementation during in vitro maturation on the development of embryos following injection of mouse iPS cells into blastocysts*.

Group**	No. of injected blastocyst	No. (%) of blastocysts
		Re-expanded	Hatched
Control	54	36 ( 66.9 ± 4.8)	3 ( 6.4 ± 2.4)^a
CGA	57	31 ( 59.7 ± 10.3)	12 ( 22.1 ± 4.0)^b
ITS	64	40 ( 64.9 ± 4.9)	6 ( 8.9 ± 1.2)^a
CGA + ITS	60	39 ( 67.0 ± 6.4)	12 ( 20.8 ± 5.9)^b

*All of the experiments were repeated four times. Data are expressed as the mean ± SEM.

**As a control, oocytes were cultured in a maturation medium containing β-mercaptoethanol but not CGA and ITS.

^a,b Values with different superscript letters in the same column are significantly different (P < 0.05).