title: The spatio-temporal expression of MHC class I molecules during human hippocampal formation development.
abstract: In the immune system, the major histocompatibility complex (MHC) class I molecules mediate both the innate and adaptive immune responses in vertebrates. There has been a dogma that the central nervous system (CNS) is immune privileged and healthy neurons do not express MHC class I molecules. However, recent studies have indicated that the expression and non-immunobiologic roles of MHC class I in mammalian CNS. But data referring to humans are scarce. In this study we report the expression and cellular localization of MHC class I in the human fetal, early postnatal and adult hippocampal formation. The expression of MHC class I was very low in the hippocampus at 20 (gestational weeks) GW and slowly increased at 27-33 GW. The gradually increased expression in the somata of some granular cells in dentate gyrus (DG) was observed at 30-33 GW. Whereas, a rapid increase in MHC class I molecules expression was found in the subiculum and it reached high levels at 31-33 GW and maintained at postnatal 55 days. No expression of MHC class I was found in hippocampal formation in adult. MHC class I heavy chain and β2 microglobulin (β2M) showed similar expression in some cells of the hippocampal formation at 30-33 GW. Moreover, MHC class I molecules were mainly expressed in neurons and most MHC class I-expressing neurons were glutamatergic. The temporal and spatial patterns of MHC class I expression appeared to follow gradients of pyramidal neurons maturation in the subiculum at prenatal stages and suggested that MHC class I molecules are likely to regulate neuron maturation. This article is part of a Special Issue entitled Priority to Publish.
authors.affiliation: Key Laboratory of Developmental Genes and Human Disease, Ministry of Education, Department of Microbiology and Immunology, Medical School, Southeast University, Nanjing, Jiangsu 210009, China.
authors.forename: Aifeng
authors.initials: A
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Yu
authors.forename: Youji
authors.initials: Y
authors.lastname: He
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Shen
authors.forename: Ning
authors.initials: N
authors.lastname: Pan
authors.forename: Jiane
authors.initials: J
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Fu
authors.forename: Fengqin
authors.initials: F
authors.lastname: Miao
authors.forename: Jianqiong
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000328:Adult; D001344:Autopsy; D001609:Beta-Globulins / Q000378:metabolism; D001921:Brain / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development; D005333:Fetus; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D005865:Gestational Age; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006624:Hippocampus / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D007223:Infant; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D001609:Beta-Globulins; D005904:Glial Fibrillary Acidic Protein; D015395:Histocompatibility Antigens Class I; D009419:Nerve Tissue Proteins; C493464:SLC17A7 protein, human; D050598:Vesicular Glutamate Transport Protein 1; D005680:gamma-Aminobutyric Acid; D010751:Phosphopyruvate Hydratase
keywords: Hippocampal formation; Human neural development; Immunofluorescence; Immunohistochemistry; MHC class I