Elsevier

Clinical Immunology

Volume 122, Issue 1, January 2007, Pages 41-52
Clinical Immunology

Murine experimental autoimmune gastritis models refractive to development of intrinsic factor autoantibodies, cobalamin deficiency and pernicious anemia

https://doi.org/10.1016/j.clim.2006.08.013Get rights and content

Abstract

Researchers have developed murine lymphopenic, non-lymphopenic, transgenic, spontaneous and infectious agent based models to induce an experimental autoimmune gastritis (EAG) for the study of human organ-specific autoimmune disease. These models result in a chronic inflammatory mononuclear cell infiltrate in the gastric mucosa, destruction of parietal and zymogenic cells with autoantibodies reactive to the gastric parietal cells and the gastric H+/K+ ATPase (ATP4), arguably hallmarks of a human autoimmune gastritis (AIG). In the case of AIG, it is well documented that, in addition to parietal cell antibodies being detected in up to 90% of patients, up to 70% have intrinsic factor antibodies with the later antibodies considered highly specific to patients with pernicious anemia. This is the first report specifically investigating the occurrence of intrinsic factor antibodies, cobalamin deficiency and pernicious anemia in EAG models. We conclude, in contrast to AIG, that, in the three EAG models examined, intrinsic factor is not selected as a critical autoantigen.

Introduction

Cobalamin (vitamin B12) deficiency is a common cause of macrocytic anemia and has been implicated in a spectrum of neuropsychiatric disorders [1]. Pernicious anemia is generally the cause of cobalamin deficiency in Western populations with an incidence of around 1.9% in persons over 60 years of age [2]. Human autoimmune gastritis (type A chronic atrophic gastritis) is considered the underlying pathological lesion of pernicious anemia [3], [4]. The gastric lesion, confined to the fundus and body of the stomach, is characterized by an inflammatory infiltrate within the gastric mucosa, and the loss of parietal and zymogenic cells from gastric glands [4]. Most patients with pernicious anemia have circulating autoantibodies reactive to ATP4 (the proton pump), present on and in parietal cells (∼ 85%) and to intrinsic factor (∼ 60%) [5]. Intrinsic factor, secreted by stomach parietal cells in humans, promotes absorption of cobalamin in the ileum via a specific receptor-mediated endocytosis [6].

There have been many reports on murine experimental autoimmune gastritis (EAG) models arguing their relevance to the study of human autoimmune gastritis (AIG) and pernicious anemia [7], [8]. The histopathological features of gastric lesions in patients with chronic atrophic gastritis and murine EAG are similar [9], [10]. It is also well documented that all murine EAG models can result in the development of circulating antibodies reactive to parietal cells and the proton pump (ATP4A and B). However, there are no reports as to whether murine EAG results in circulating antibodies reactive to intrinsic factor, or the development of a cobalamin deficiency and subsequent macrocytic anemia.

Here we report on the incidence of circulating antibodies reactive to intrinsic factor, levels of cobalamin in blood and evidence of anemia in mice subjected to the immunization (imm:EAG), neonatal thymectomy (nTx:EAG) and a transgenic model carrying a granulocyte macrophage colony stimulating factor (GMCSF) transgene whose expression is controlled by the ATP4 β subunit promoter (PC-GMCSF:EAG).

Section snippets

Mice

BALB/cCrSlc mice were immunized intraperitoneally at 24 h, 72 h and between 20 to 21 days after birth with 7.5 μg crude gastric membranes [11] (n = 39). Neonatal thymectomy (nTx) (n = 59) was performed on 3-day old BALB/cCrSlc mice under cold anesthesia, as previously described in Alderuccio et al. [12]. Transgenic PC-GMCSF mice were identified by PCR of genomic DNA isolated from tails, using the method previously described by Biondo et al. [13] (n = 31). In addition, normal age matched BALB/cCrSlc

EAG model cohorts

Three disparate models, that utilize alternative modes of EAG induction, were selected for use in this study (Fig. 1a). The most popularly exploited neonatal thymectomy model (nTx:EAG) generates a state of transient lymphopenia [20]; the non-lymphopenic immunization model (imm:EAG) exploits gastric ATP4 in the absence of adjuvant as an immunogen breaking tolerance [11], [21], [22]; and the transgenic model utilizes a granulocyte macrophage colony stimulating factor (GMCSF) transgene whose

Discussion

The first reports of animal models (canine) to investigate autoimmune gastritis date back to the early sixties [23]. Current mouse models, utilizing the inbred BALB/c strain and neonatal thymectomy, were initiated by work of Ansar and Penhale [24]. Decades later researchers in this field have developed and exploited lymphopenic, non-lymphopenic, transgenic, spontaneous and infectious agent experimental gastritis models for the study of human organ-specific autoimmune disease [8]. In the case of

Acknowledgments

D.L.V.G was supported by a NH&MRC Biomedical (Dora Lush) Research Scholarship. The authors would like to acknowledge the assistance of: Damian McVeigh of the Alfred Pathology Service for interpretation of blood films; Ms Valentina Dubljevic for assistance with the M(H)6mrGIF construct and Mr. Michael Bailey, Monash University Department of Epidemiology and Preventive Medicine for statistical analysis.

References (50)

  • R. Oh et al.

    Vitamin B12 deficiency

    Am. Fam. Phys.

    (2003)
  • R. Carmel

    Prevalence of undiagnosed pernicious anemia in the elderly

    Arch. Intern. Med.

    (1996)
  • R.G. Strickl et al.

    A reappraisal of the nature and significance of chronic atrophic gastritis

    Am. J. Dig. Dis.

    (1973)
  • B.H. Toh et al.

    The gastric H/K ATPase in the pathogenesis of autoimmune gastritis

  • K.B. Taylor et al.

    Autoimmune phenomena in pernicious anaemia: gastric antibodies

    Br. Med. J.

    (1962)
  • G.J. Russell-Jones et al.

    Vitamin B12 transporters

    Pharm. Biotechnol.

    (1999)
  • J. Field et al.

    Experimental autoimmune gastritis: mouse models of human organ-specific autoimmune disease

    Int. Rev. Immunol.

    (2005)
  • B.H. Toh et al.

    Autoimmunity: a paradigm of autoimmune gastritis

    Today's Life Sci.

    (1993)
  • K.J. Scarff et al.

    Immunization with gastric H+/K+-ATPase induces a reversible autoimmune gastritis

    Immunol

    (1997)
  • D.L.V. Greenwood et al.

    Characterisation of Proton pump antibodies and stomach pathology in gastritis induced by neonatal immunisation without adjuvant

    Autoimmunity

    (2001)
  • F. Alderuccio et al.

    An autoimmune disease with multiple molecular targets abrogated by the transgenic expression of a single autoantigen in the thymus

    J. Exp. Med.

    (1993)
  • M. Biondo et al.

    Local transgenic expression of granulocyte macrophage-colony stimulating factor initiates autoimmunity

    J. Immunol.

    (2001)
  • J.M. Callaghan et al.

    Rapid purification of the gastric H+/K+-ATPase complex by tomato-lectin affinity chromotography

    Biochem. J.

    (1992)
  • U. Laemmli

    Cleavage of structural proteins during the assembly of head bacteriophage T4

    Nature

    (1970)
  • R.A.B. Dury et al.

    Carlton's Histological Technique

    (1967)
  • Cited by (4)

    1

    Current address: Centre for Animal Biotechnology, Department of Veterinary Science, The University of Melbourne, Parkville, Victoria 3010, Australia.

    View full text