Distribution of rat neonatal Fc receptor in the principal organs of neonatal and pubertal rats

Abstract

The neonatal Fc receptor (FcRn) mediates the transfer of IgG and albumin, also protects them from catabolism. This study characterized the expression of FcRn in different organs of neonatal and pubertal rats by reverse transcription-PCR (RT-PCR) and immunohistochemistry, demonstrates that FcRn is expressed in liver, kidney, intestine, heart, lung, spleen, skin and skeletal muscles at varying levels post-gestation from d 1 to d 63. This finding is contrary to previous studies claiming that FcRn is undetectable in most tissues after weaning. Lungs were the predominant organs for FcRn expression, whereas skin, liver and intestine are considerably less expressed organs. The expression of FcRn fluctuated in all the organs tested, and with a higher frequency before weaning compared to puberty. These findings may provide clues for the better understanding of FcRn function, and are important for determining the dosage levels for IgG and the constant region fragment (Fc)-containing therapeutic proteins whose half-life is regulated by FcRn.

TGEV infection up-regulates FcRn expression via activation of NF-κB signaling

“…FcRn has more recently been shown to express in a variety of mammalian species 12 . Meanwhile, several studies have reported the distribution, function, and regulation of human and rodent FcRn expression 9,24,29,30 . Our study demonstrated that pFcRn mediated bidirectional IgG transport across polarized IPEC-J2 cells that potentially provide the mucosal protection 31 .…”

A comprehensive review of the neonatal Fc receptor and its application in drug delivery

“…Prevention of IgG and albumin loss through the biliary system. McCarthy et al, 2000;Pike et al, 2013;Simister et al, 1996;Tian et al, 2014;Tzaban et al, 2009) Breast Transfer of passive immunity and tolerance induction. Albumin transport.…”

Integration of Ontogeny Into a Physiologically Based Pharmacokinetic Model for Monoclonal Antibodies in Premature Infants

“…The availability of FcRn for intracellular salvage is a key determinant of plasma half‐life. Some preliminary data may suggest lower FcRn concentrations in children, though no definitive argument can yet be made . Three studies have examined FcRn expression in neonatal subjects relative to adults .…”

“…Some preliminary data may suggest lower FcRn concentrations in children, though no definitive argument can yet be made . Three studies have examined FcRn expression in neonatal subjects relative to adults . In rats, reverse transcriptase polymerase chain reaction revealed a general trend across all organs of low FcRn mRNA expression at birth relative to adults, though the intestine may be an exception .…”