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Many chemokines are present at the maternal-fetal interface and play important roles in the establishment and maintenance of pregnancy. Our study demonstrates that a chemokine, chemokine (C-C motif) ligand 28 (CCL28), is expressed in the uterine endometrium during early pregnancy in pigs. Thus, we investigated expression ofCCL28and its receptors, chemokine (C-C motif) receptor types 3 (CCR3) and 10 (CCR10), in the uterine endometrium during the estrous cycle and pregnancy and the function of CCL28 at the maternal-fetal interface during early pregnancy. Levels ofCCL28mRNAs were highest on Day 10 of pregnancy and decreased thereafter during pregnancy, andCCL28was localized mainly to endometrial glandular epithelial cells. The presence of the CCL28 protein in uterine flushings was confirmed on Day 12 of the estrous cycle and pregnancy. Endometrial tissues expressedCCR3andCCR10during pregnancy. The CCR10 protein was localized to endometrial luminal and glandular epithelial cells, chorionic epithelial cells, and the allantoic membrane during pregnancy. Conceptuses during early pregnancy expressedCCL28andCCR10, but notCCR3, and chorioallantoic tissues expressedCCR10at increasing levels towards term. Treatment with recombinant CCL28 increased the proliferation and migration of a porcine trophectoderm cell line. These results indicated that theCCL28chemokine and its receptors,CCR3andCCR10, are expressed at the maternal-conceptus interface, and CCL28 induces the proliferation and migration of trophectoderm cells through CCR10, suggesting that CCL28 may play a critical role in the establishment and maintenance of pregnancy in pigs.