Functional analysis of the mouse J chain

Research output: ThesisDoctoral Thesis (compilation)


We have in this study analyzed the function of the murine Joining chain (J chain) in vivo. J chain is a polypeptide found in sera and secretions in complex with pentameric IgM and dimeric IgA. J chain is expressed in terminally differentiated B lymphocytes and needed for the transport of dimeric IgA and pentameric IgM over mucosal surfaces via the poly Ig receptor. A mouse deficient for J chain was generated and it was shown that J chain in vivo seems to be necessary for efficient assembly and secretion of polymeric IgM. Secondly, in the absence of J chain, antigen-specific IgA immunity in the lamina propria of the mucosa cannot mediate protection on the mucosal surface of the intestinal lumen; thereby demonstrating in vivo a direct relationship between mucosal transport of secretory IgA and intestinal immune protection. A second mouse was generated where the Diphtheria toxin A gene was introduced into the J chain locus, thereby ablating J chain expressing cells. Evidence was found for the existence of two separate plasma cell populations distinguishable by the absence or the presence of J chain. The dogma that in mice the J chain is expressed in all plasma cells irrespective of isotype has been challenged.


  • Lena Erlandsson
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Immunology in the medical area


  • Immunology, diphtheria toxin A, plasma cell, mucosa, J chain, knock-out, serology, transplantation, Immunologi, serologi
Original languageEnglish
Awarding Institution
Supervisors/Assistant supervisor
  • [unknown], [unknown], Supervisor, External person
Award date1999 May 5
  • Immunology Unit, Sölvegatan 21, 223 62 Lund, Sweden
Print ISBNs91-628-3544-0
Publication statusPublished - 1999
Publication categoryResearch

Bibliographic note

Defence details Date: 1999-05-05 Time: 10:15 Place: Sölvegatan 21, Lund External reviewer(s) Name: Sideras, Paschalis Title: Dr Affiliation: Umeå University, Sweden ---