The FcRn from gene to protein and function: comparison between species

Immunoglobulin Fc receptors are crucial molecules in immunological processes that help maintain homeostasis following internal or external stimuli. Most of the specific gamma recognition molecules (FcγRI, II, and III) are known for their roles in phagocytosis and cellular cytotoxicity against variou...

Full description

Saved in:
Bibliographic Details
Main Authors: Luz Belinda Ortiz-Alegría, Lizbeth Xicoténcatl-García, Irma Cañedo-Solares, Claudia Patricia Rico-Torres, Fernando Gómez-Chávez
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-08-01
Series:Frontiers in Immunology
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fimmu.2025.1608426/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849247122776391680
author Luz Belinda Ortiz-Alegría
Lizbeth Xicoténcatl-García
Irma Cañedo-Solares
Claudia Patricia Rico-Torres
Fernando Gómez-Chávez
author_facet Luz Belinda Ortiz-Alegría
Lizbeth Xicoténcatl-García
Irma Cañedo-Solares
Claudia Patricia Rico-Torres
Fernando Gómez-Chávez
author_sort Luz Belinda Ortiz-Alegría
collection DOAJ
description Immunoglobulin Fc receptors are crucial molecules in immunological processes that help maintain homeostasis following internal or external stimuli. Most of the specific gamma recognition molecules (FcγRI, II, and III) are known for their roles in phagocytosis and cellular cytotoxicity against various pathogens and transformed cells and in regulating the humoral immune response. Within this family of IgG Fc receptors, there is a structurally similar receptor with different functions: the so-called neonatal receptor for the Fc fraction of IgG, or FcRn, which is primarily associated with IgG and albumin homeostasis, the transfer of immunity from mother to offspring, and the regulation of the immune response in mammals. Therefore, this molecule could be considered “the regulator and transporter of the main blood proteins” from the blood vessels and the lumen of the mucosa to the tissues of the newborn and neonate, through the epithelium and endothelium. It may act as a trans-tissue and interindividual “protector,” as it mediates the transfer of IgG antibodies to the sites where they are needed. Additionally, it regulates plasma albumin and IgG concentrations, contributing to the balance of body fluids. Although there is abundant literature on this receptor, some phenomena remain unexplored or poorly understood. In particular, the variations in its functions across different cell types and between species, how they influence IgG and albumin levels in various body fluids, and the pathways involved in immunity transmission need further investigation. In this paper, we present a comprehensive review of original research articles and analyses focused on the gene, mRNA, and protein composition of the FcRn, with the aim to compare the genetic, structural, and functional characteristics in different mammalian species, focusing on its role in immunity and homeostasis, as well as the ontogeny and phylogeny of the FcRn.
format Article
id doaj-art-e56127ef96ef44e5932a4761103ee308
institution Kabale University
issn 1664-3224
language English
publishDate 2025-08-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Immunology
spelling doaj-art-e56127ef96ef44e5932a4761103ee3082025-08-20T03:58:18ZengFrontiers Media S.A.Frontiers in Immunology1664-32242025-08-011610.3389/fimmu.2025.16084261608426The FcRn from gene to protein and function: comparison between speciesLuz Belinda Ortiz-Alegría0Lizbeth Xicoténcatl-García1Irma Cañedo-Solares2Claudia Patricia Rico-Torres3Fernando Gómez-Chávez4Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, MexicoLaboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, MexicoLaboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, MexicoLaboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, MexicoLaboratorio de Enfermedades Osteoarticulares e Inmunológicas, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Mexico City, MexicoImmunoglobulin Fc receptors are crucial molecules in immunological processes that help maintain homeostasis following internal or external stimuli. Most of the specific gamma recognition molecules (FcγRI, II, and III) are known for their roles in phagocytosis and cellular cytotoxicity against various pathogens and transformed cells and in regulating the humoral immune response. Within this family of IgG Fc receptors, there is a structurally similar receptor with different functions: the so-called neonatal receptor for the Fc fraction of IgG, or FcRn, which is primarily associated with IgG and albumin homeostasis, the transfer of immunity from mother to offspring, and the regulation of the immune response in mammals. Therefore, this molecule could be considered “the regulator and transporter of the main blood proteins” from the blood vessels and the lumen of the mucosa to the tissues of the newborn and neonate, through the epithelium and endothelium. It may act as a trans-tissue and interindividual “protector,” as it mediates the transfer of IgG antibodies to the sites where they are needed. Additionally, it regulates plasma albumin and IgG concentrations, contributing to the balance of body fluids. Although there is abundant literature on this receptor, some phenomena remain unexplored or poorly understood. In particular, the variations in its functions across different cell types and between species, how they influence IgG and albumin levels in various body fluids, and the pathways involved in immunity transmission need further investigation. In this paper, we present a comprehensive review of original research articles and analyses focused on the gene, mRNA, and protein composition of the FcRn, with the aim to compare the genetic, structural, and functional characteristics in different mammalian species, focusing on its role in immunity and homeostasis, as well as the ontogeny and phylogeny of the FcRn.https://www.frontiersin.org/articles/10.3389/fimmu.2025.1608426/fullFcRnspeciesIgGalbuminphylogenyontogeny
spellingShingle Luz Belinda Ortiz-Alegría
Lizbeth Xicoténcatl-García
Irma Cañedo-Solares
Claudia Patricia Rico-Torres
Fernando Gómez-Chávez
The FcRn from gene to protein and function: comparison between species
Frontiers in Immunology
FcRn
species
IgG
albumin
phylogeny
ontogeny
title The FcRn from gene to protein and function: comparison between species
title_full The FcRn from gene to protein and function: comparison between species
title_fullStr The FcRn from gene to protein and function: comparison between species
title_full_unstemmed The FcRn from gene to protein and function: comparison between species
title_short The FcRn from gene to protein and function: comparison between species
title_sort fcrn from gene to protein and function comparison between species
topic FcRn
species
IgG
albumin
phylogeny
ontogeny
url https://www.frontiersin.org/articles/10.3389/fimmu.2025.1608426/full
work_keys_str_mv AT luzbelindaortizalegria thefcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT lizbethxicotencatlgarcia thefcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT irmacanedosolares thefcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT claudiapatriciaricotorres thefcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT fernandogomezchavez thefcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT luzbelindaortizalegria fcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT lizbethxicotencatlgarcia fcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT irmacanedosolares fcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT claudiapatriciaricotorres fcrnfromgenetoproteinandfunctioncomparisonbetweenspecies
AT fernandogomezchavez fcrnfromgenetoproteinandfunctioncomparisonbetweenspecies