Expression of the Fc receptor in the mammary gland during lactation in the marsupial Trichosurus vulpecula (brushtail possum)

• Published in: Molecular immunology Vol. 37; no. 8; pp. 435 - 444
• Main Authors: Adamski, Frances M, King, Andrea T, Demmer, Jerome
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.06.2000
• Subjects: AFc receptors; Animals; Antibodies; b2-microglobulin; beta 2-Microglobulin - chemistry; beta 2-Microglobulin - genetics; beta 2-Microglobulin - metabolism; Binding Sites; Blotting, Northern; Cattle; Cloning, Molecular; Fc receptors; Female; Gene Expression Regulation, Developmental; Humans; Immunoglobulin Fc Fragments - chemistry; Immunoglobulin Fc Fragments - immunology; Immunoglobulin Fc Fragments - metabolism; Immunoglobulin G - chemistry; Immunoglobulin G - immunology; Immunoglobulin G - metabolism; Lactation - genetics; Lactation - immunology; Lactation - metabolism; Mammary Glands, Animal - growth & development; Mammary Glands, Animal - immunology; Mammary Glands, Animal - metabolism; Marsupialia - genetics; Marsupialia - immunology; Marsupialia - metabolism; Mice; Milk - immunology; Milk - metabolism; Molecular biology; Molecular Sequence Data; Protein Binding; Receptors, Fc - chemistry; Receptors, Fc - genetics; Receptors, Fc - metabolism; Reproductive immunology; RNA, Messenger - genetics; RNA, Messenger - metabolism; Sequence Alignment; Transporters; Trichosurus vulpecula; Fc receptors; PY, pouch young; Antibodies; Transporters; Reproductive immunology; β-2m, beta-2 microglobulin; Molecular biology
• ISSN: 0161-5890; 1872-9142
• DOI: 10.1016/S0161-5890(00)00065-1

One of several functions described for the Fc receptor is regulation of IgG isotype transport into milk. The first marsupial homologues of the Fc receptor heavy and light chains, FcRn and β-2 microglobulin, from the brushtail possum have been cloned and characterised. The level of FcRn mRNA in the possum mammary gland was highest at the start of lactation, and decreased slowly thereafter. Expression of FcRn mRNA did not increase during the switch phase when the concentration of IgG in milk is highest. In contrast, the level of β-2 microglobulin mRNA in the mammary gland increased during the switch phase when milk IgG concentration also increases. This correlation between β-2 microglobulin mRNA expression in the mammary gland with the time of active IgG-transfer into milk was also observed in the bovine and murine mammary gland. This suggests that expression of the Fc receptor in the mammary gland is controlled by the expression of β-2 microglobulin and that its expression is upregulated during the period of highest IgG-transfer into milk.