Evidence map›Paper›PMID 41604261›Full record

ArticleProceedings of the National Academy of Sciences of the United States of America2026

FcγRIIB functions as an IgG transporter in the mammary gland.

Xin Li, Lijuan Du, Zihui Wan, Zhiren Jin, Yuanhao Peng, Yongliang Fan, Cuncun Ke, Yonghe Ma, Haitang Han, Shuyang Yu and 10 more

Abstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Proceedings of the National Academy of Sciences of the United States of America, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

20 authors.

Xin Li *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.ORCID 0009-0008-9747-0741
Lijuan Du *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Zihui Wan *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Zhiren JinState Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Yuanhao PengState Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Yongliang FanState Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China.
Cuncun KeState Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Yonghe MaState Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Haitang HanState Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.
Shuyang YuState Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.ORCID 0000-0002-4686-3296
Gengsheng CaoHenan Province Livestock Gene Editing Biotechnology Breeding Engineering Center, School of Life Sciences, Henan University, Kaifeng, Henan 475000, China.
Tian HuangHenan Province Livestock Gene Editing Biotechnology Breeding Engineering Center, School of Life Sciences, Henan University, Kaifeng, Henan 475000, China.
Qiang Pan-HammarströmDivision of Immunology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden.
Lennart HammarströmDivision of Immunology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17177, Sweden.ORCID 0000-0002-8635-9609
Ning LiBeijing Capital Agribusiness Future Biotechnology Co., Ltd., Beijing 100088, China.
Mingzhou LiState Key Laboratory of Swine and Poultry Breeding Industry, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu 611130, China.ORCID 0000-0001-8681-7684
Ran Zhang *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.ORCID 0000-0002-3452-8917
Xuguang Du *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.ORCID 0000-0001-9032-8330
Dengke Pan *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.ORCID 0000-0002-7994-1465
Yaofeng Zhao *State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, National Engineering Laboratory for Animal Breeding, Frontiers Science Center for Molecular Design Breeding, China Agricultural University, Beijing 100193, China.ORCID 0000-0003-4499-8610

Funding

MOST | National Key Research and Development Program of China (NKPs) 2021YFA0805905MOST | National Key Research and Development Program of China (NKPs) 2023YFF1000900MOST | National Natural Science Foundation of China (NSFC) 31530070
6 · The paper itself

Abstract

In mammals, passive acquisition of maternal immunoglobulins is essential for neonatal immune development and defense against infections. IgG, a central mediator of humoral immunity, is maternally transferred via distinct mechanisms depending on placental structure in placental mammals. In humans (hemochorial placenta), IgG is prenatally transported across the placenta, whereas in large domestic animals such as pigs and cows (epitheliochorial/connective chorionic placenta), IgG is exclusively transferred postnatally via colostrum and absorbed in the neonatal intestine. Rodents (allantoic chorionic placenta) employ both pathways. Critically, IgG must traverse multiple tissue barriers-including the placenta, mammary gland, and neonatal intestine-to reach the circulation of newborns. While FcRn is known to facilitate IgG transport in the placenta and neonatal intestine, the mechanisms underlying IgG secretion into milk remain unclear. Here, we identify FcγRIIB as the key transporter mediating maternal IgG transfer across the mammary gland in mammals. Using constitutive and conditional knockout mice, we demonstrate that FcγRIIB deficiency impairs mammary IgG transfer, whereas its overexpression enhances milk IgG levels. Strikingly, in pigs, FcγRIIB is highly upregulated in mammary tissue prepartum, and its disruption abolishes IgG accumulation in colostrum. Our work opens avenues for improving neonatal immunity through targeted modulation of FcγRIIB-mediated IgG transport.

Indexed as

Immunoglobulin GMammary Glands, AnimalReceptors, IgGAnimalsColostrumFemaleMiceMice, KnockoutMilkPlacentaPregnancyReceptors, FcSwineFcgr2b protein, mouseImmunoglobulin GReceptors, FcReceptors, IgGFcRnFcγRIIBmammary glandmaternal IgG transferpigs

Identifiers

PMID41604261
PMCPMC12867736

What Socratic holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.