Alan D. Ealy, Ph.D.

The overall goal of our research program is to elucidate the key physiological, endocrine and molecular mechanisms responsible for conceptus development and subsequent establishment and maintenance of pregnancy in ruminants.  From 20 to 40% of all fertile matings in cattle do not result in the birth of a live calf, and a majority of these losses occur within the first month of pregnancy.  Failures in conceptus elongation and maternal recognition of pregnancy undoubtedly contribute to pregnancy loss.  By improving our understanding of the basic biology of embryogenesis and placentation, management schemes can be created to reduce embryonic losses in production livestock.  Work in the laboratory focuses on two areas:     

Early Placental Development: The outer-most layer of the fetal placenta, termed the trophectoderm, undergoes extensive proliferation prior to its attachment to the uterine lining in cattle, sheep and other ruminants.  The laboratory is using a combination of in utero, in vitro and molecular technologies to identify uterine- and conceptus-derived factors that regulate the rate of trophectoderm proliferation.  Our present efforts have focused on defining how fibroblast growth factors, namely FGF-2 and FGF-4, mediate early placental development.    

Regulation of Placental Gene Expression:  In ruminants, the developing conceptus must communicate with the maternal system before placentation begins to establish and maintain a uterine environment that is conducive for pregnancy.  Interferon-tau (IFN-t) is the hormone responsible for maintenance of pregnancy in ruminants.  It is secreted by the trophectoderm and interacts with the uterine lining to prevent corpus luteum regression and return to estrus.  The temporal and spatial expression pattern of IFN-t is well documented, but the endocrine and molecular mechanisms that regulate IFN-t gene expression remain largely undefined.  Our laboratory is identifying and characterizing the uterine-derived factors that influence IFN-t gene expression.   

 Representative Publications:

Ocón-Grove O M, Cooke FN, Alvarez IM, Johnson SE, Ott TL and Ealy AD. 2007.  Ovine endometrial expression of fibroblast growth factor (FGF) 2 and conceptus expression of FGF receptors during early pregnancy. Domest. Anim. Endocrinol. In press.

Talbot NC, Powell AM, Camp M and Ealy AD.  2007. Establishment of a bovine blastocyst-derived cell line collection for the comparative analysis of embryos created in vivo and by in vitro fertilization, somatic cell nuclear transfer, or parthenogenetic activation. In Vitro Cell Dev. Biol. Anim. 43:59-71.

Chen Y, Green JA, Antoniou E, Ealy AD, Mathialagan NP, Walker AM, Avalle MP, Rosenfeld CS, Hearne LB and Roberts RM. 2006.  Effect of interferon-tau administration on endometrium of non-pregnant ewes: a comparison with pregnant ewes.  Endocrinology 147:2127-2137.

Ealy AD, Pennington KA and Rodina TM. 2006. Interferon-tau polymorphisms and their potential functions in ruminants. Ann. Rev. Biomed. Sci. 8:9-18. 

Michael DD, Alvarez IM, Ocón OM, Powell AM, Talbot NC, Johnson SE and Ealy AD.  2006.  Fibroblast growth factor-2 is expressed by the bovine uterus and stimulates interferon-tau production in bovine trophectoderm. Endocrinology 147:3571-3579.

Michael DD, Wagner SK, Ocón OM, Talbot NC, Rooke JA and Ealy AD. 2006.  Granulocyte-Macrophage Colony-Stimulating-Factor Increases Interferon-tau Protein Secretion in Bovine Trophectoderm Cells.  Am. J. Reprod. Immunol. 56:63-67.

Ealy AD, Wagner SK, Shiels AE, Whitley N, Keisling DO, Johnson SE and Barbato GF. 2004.  Identification of interferon-tau isoforms expressed by the prei-implantation goat (Capra hircus) conceptus.  Domest. Anim. Endocrinol. 27:39-49.

Talbot NC, Caperna TJ, Powell AM, Garrett WM and Ealy AD. 2004.  Isolation and characterization of a bovine trophectoderm cell line derived from a parthenogenetic blastocyst.  Mol. Reprod. Dev. 69:164-173.

Roberts RM, Ezashi T, Rosenfeld CS, Ealy AD and Kubisch HM. 2003. Evolution of the interferon tau genes and their promoters, and maternal-trophoblast interactions in control of their expression. Reproduction Suppl. 61: 239-251.