Bovine Early Pregnancy Factor: Purification and Biochemical Examination

Bovine Early Pregnancy Factor: Its Characterization and an Attempt to Produce Anti-Bovine EPF Antibody.

“…In a previous study [12], we reported that the isoelectric point of EPF (21.5 KD) was near pI 5.0 and the EPF active fraction had three bands between 20-30 KD by SDS-PAGE. However, in the present study, the corresponding bands were stained as four dots on the two dimension electrophoregram, and the isoelectric points centered around 6.3 (Fig.…”

“…6.8 in mice. We reported that the isoelectric point of bovine EPF was approximately 5.0 [12], but it could not be definitively determined which of the four bands corresponded to the stained dots on 2D SDS-PAGE [12]. To clarify this point, we attempted again to determine the isoelectric point of the putative EPF.…”

“…24-30 KD, pI 3.5-3.75. in cattle, Klima et al [10] reported that the molecular weight of bovine EPF was 67 KD; in parallel investigations of nonpregnant cattle, they also identified a 67 kDa polypeptide, but it lacked EPF activity in RIT. On the other hand, we [11,12] reported that the EPF-active fraction purified from pregnant bovine serum 8 days after artificial insemination (A.I.) had four proteins between M.W.…”

“…We attempted to purify EPF using Sepharose 4B affinity chromatography coupled with the adsorbed EPF-IgG. The 10-100 KD fraction (RIT= 6) [12] was divided into the unadsorbed fraction and adsorbed fraction by this column. The RIT values of these fractions were 4 and 5, respectively.…”

Isolation and Purification of Early Pregnancy Factor (EPF) in Rat Serum.

“…In cattle, Klima et al [16] reported that the M. W. of bovine EPF was 67 KD. On the other hand, Ito et al [17] and Ito and Yasuda [12] reported that the EPF-active fraction purified from pregnant bovine serum 8 days after artificial insemination had 4 proteins between M. W. 20 KD and 30 KD; only the protein of M. W. 21.5 KD was absent in non-pregnant serum.…”