Immunoglobulin A (IgA) Polymerization Sites in Human Immunocytes: Immunoelectron Microscopic Study

Cell Structure and Function

Takashi Iwase¹  Zina Moldoveanu¹  Itaru Moro¹  Kazuo Komiyama¹  Jiri Mestecky¹ 

[1] Department of Pathology, Nihon University School of Dentistry

关键词: Immunoglobulin A;    Polymerization;    J chain;    Secretory component binding;    Immunoelectron microscopy;   

DOI  :  10.1247/csf.15.85

学科分类：分子生物学，细胞生物学和基因

来源: Japan Society for Cell Biology

【 摘 要 】

References(36)Cited-By(4)The cytoplasmic affinity of polymeric IgA for secretory component (SC) and the expression of joining (J) chain were examined in pokeweed mitogen (PWM)-stimulated human peripheral blood lymphocytes (PBL) to determine, on the ultrastructural level, the polymerization sites of human IgA. SC-binding was found in 5.7% of transformed PBL on day 7 of culture; SC-binding was observed in a high proportion of IgA-producing cells. A low proportion of IgM-producing cells also bound to SC, while there was virtually no SC-binding by IgG-producing cells. A high proportion of IgA- and IgM-producing cells expressed intracellular J chain, while approximately half of the IgG-producing cells were positive for J chain. The number of J chain-positive cells exceeded the number of SC-binding cells among transformed PBL on day 7 of culture. Immunoelectron microscopic study of the sites of SC-binding, and of IgA and J chain expression, revealed that polymerization of human IgA and the addition of J chain occur in the perinuclear space and endoplasmic reticulum, prior to immunoglobulin secretion.

【 授权许可】

Unknown