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The cellular location of self-antigen determines the positive and negative selection of autoreactive B cells.

Ferry H, Jones M, Vaux DJ, Roberts IS, Cornall RJ - J. Exp. Med. (2003)

Bottom Line: To test for differences in the B cell response to intracellular and extracellular self-antigens, we sequestered a tolerogenic cell surface antigen intracellularly by addition of a two amino acid endoplasmic reticulum (ER) retention signal.In contrast to cell surface antigen, which causes the deletion of autoreactive B cells, the intracellularly sequestered self-antigen failed to induce B cell tolerance and was instead autoimmunogenic.The intracellular antigen positively selected antigen-binding B cells to differentiate into B1 cells and induced large numbers of IgM autoantibody-secreting plasma cells in a T-independent manner.

View Article: PubMed Central - PubMed

Affiliation: Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK.

ABSTRACT
Systemic autoimmune disease is frequently characterized by the production of autoantibodies against widely expressed intracellular self-antigens, whereas B cell tolerance to ubiquitous and highly expressed extracellular antigens is strictly enforced. To test for differences in the B cell response to intracellular and extracellular self-antigens, we sequestered a tolerogenic cell surface antigen intracellularly by addition of a two amino acid endoplasmic reticulum (ER) retention signal. In contrast to cell surface antigen, which causes the deletion of autoreactive B cells, the intracellularly sequestered self-antigen failed to induce B cell tolerance and was instead autoimmunogenic. The intracellular antigen positively selected antigen-binding B cells to differentiate into B1 cells and induced large numbers of IgM autoantibody-secreting plasma cells in a T-independent manner. By analyzing the impact of differences in subcellular distribution independently from other variables, such as B cell receptor affinity, antigen type, or tissue distribution, we have established that intracellular localization of autoantigen predisposes for autoantibody production. These findings help explain why intracellular antigens are targeted in systemic autoimmune diseases.

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Intracellular HEL autoantigen triggers autoantibody production. (A) Serum anti-HEL IgMa titers in Ig, mHEL-KK Dbl, and nontransgenic (non) mice as determined by ELISA. Dots show geometric means, and bars represent the 95% confidence limits. The background is twice the level in blank wells. (B) Anti-HEL IgMa-secreting plasma cells in BM, spleen, mesenteric LN (MLN), and submandibular LN (SMLN) of Ig (white bars) and mHEL-KK Dbl mice (black bars). Columns show geometric means and bars represent the 95% confidence limits. (C) Spleen sections from Ig and mHEL-KK Dbl mice stained with antibodies to IgDa B cells (brown) and plasma cells (red).
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fig5: Intracellular HEL autoantigen triggers autoantibody production. (A) Serum anti-HEL IgMa titers in Ig, mHEL-KK Dbl, and nontransgenic (non) mice as determined by ELISA. Dots show geometric means, and bars represent the 95% confidence limits. The background is twice the level in blank wells. (B) Anti-HEL IgMa-secreting plasma cells in BM, spleen, mesenteric LN (MLN), and submandibular LN (SMLN) of Ig (white bars) and mHEL-KK Dbl mice (black bars). Columns show geometric means and bars represent the 95% confidence limits. (C) Spleen sections from Ig and mHEL-KK Dbl mice stained with antibodies to IgDa B cells (brown) and plasma cells (red).

Mentions: In striking contrast to IgHEL mice expressing cell surface or soluble forms of HEL autoantigen (1, 7, 8, 34), mice expressing intracellular HEL autoantigen contained high autoantibodiy titers and large numbers of autoantibody-secreting plasma cells (Fig. 5, A and B) . Compared with IgHEL single transgenic mice, IgHEL/mHEL-KK double transgenic mice contained 25-fold more plasma cells secreting anti-HEL IgM in the spleen and an equivalent increase in anti-HEL IgM antibodies in the serum. This corresponds to an elevation in serum antibody of >10,000 fold compared with mice expressing HEL as a cell surface autoantigen (1). Histological examination of IgHEL/mHEL-KK double transgenic spleens showed numerous plasma cells confined to the red pulp cords (Fig. 5 C). Increased numbers of HEL-specific plasma cells were not found in the BM or LNs (Fig. 5 B). A similar increase in autoantibody titers was found in all three mHEL-KK lines. To test whether autoantibody production was T cell dependent, IgHEL/mHEL-KK mice were crossed onto a Rag2−/− background. The mean number of plasma cells in the IgHEL Rag2−/− was 12,223 per spleen (95% confidence: 0–33,930; n = 4) and in IgHEL/mHEL-KK Rag2−/−was 297,267 per spleen (95% confidence: 111,577–482,956; n = 5). Therefore, in stark contrast to mHEL or sHEL (1, 7, 8) the sequestered intracellular HEL is immunogenic, inducing autoreactive plasma cells and high titre autoantibodies in a T cell–independent manner.


The cellular location of self-antigen determines the positive and negative selection of autoreactive B cells.

Ferry H, Jones M, Vaux DJ, Roberts IS, Cornall RJ - J. Exp. Med. (2003)

Intracellular HEL autoantigen triggers autoantibody production. (A) Serum anti-HEL IgMa titers in Ig, mHEL-KK Dbl, and nontransgenic (non) mice as determined by ELISA. Dots show geometric means, and bars represent the 95% confidence limits. The background is twice the level in blank wells. (B) Anti-HEL IgMa-secreting plasma cells in BM, spleen, mesenteric LN (MLN), and submandibular LN (SMLN) of Ig (white bars) and mHEL-KK Dbl mice (black bars). Columns show geometric means and bars represent the 95% confidence limits. (C) Spleen sections from Ig and mHEL-KK Dbl mice stained with antibodies to IgDa B cells (brown) and plasma cells (red).
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2194246&req=5

fig5: Intracellular HEL autoantigen triggers autoantibody production. (A) Serum anti-HEL IgMa titers in Ig, mHEL-KK Dbl, and nontransgenic (non) mice as determined by ELISA. Dots show geometric means, and bars represent the 95% confidence limits. The background is twice the level in blank wells. (B) Anti-HEL IgMa-secreting plasma cells in BM, spleen, mesenteric LN (MLN), and submandibular LN (SMLN) of Ig (white bars) and mHEL-KK Dbl mice (black bars). Columns show geometric means and bars represent the 95% confidence limits. (C) Spleen sections from Ig and mHEL-KK Dbl mice stained with antibodies to IgDa B cells (brown) and plasma cells (red).
Mentions: In striking contrast to IgHEL mice expressing cell surface or soluble forms of HEL autoantigen (1, 7, 8, 34), mice expressing intracellular HEL autoantigen contained high autoantibodiy titers and large numbers of autoantibody-secreting plasma cells (Fig. 5, A and B) . Compared with IgHEL single transgenic mice, IgHEL/mHEL-KK double transgenic mice contained 25-fold more plasma cells secreting anti-HEL IgM in the spleen and an equivalent increase in anti-HEL IgM antibodies in the serum. This corresponds to an elevation in serum antibody of >10,000 fold compared with mice expressing HEL as a cell surface autoantigen (1). Histological examination of IgHEL/mHEL-KK double transgenic spleens showed numerous plasma cells confined to the red pulp cords (Fig. 5 C). Increased numbers of HEL-specific plasma cells were not found in the BM or LNs (Fig. 5 B). A similar increase in autoantibody titers was found in all three mHEL-KK lines. To test whether autoantibody production was T cell dependent, IgHEL/mHEL-KK mice were crossed onto a Rag2−/− background. The mean number of plasma cells in the IgHEL Rag2−/− was 12,223 per spleen (95% confidence: 0–33,930; n = 4) and in IgHEL/mHEL-KK Rag2−/−was 297,267 per spleen (95% confidence: 111,577–482,956; n = 5). Therefore, in stark contrast to mHEL or sHEL (1, 7, 8) the sequestered intracellular HEL is immunogenic, inducing autoreactive plasma cells and high titre autoantibodies in a T cell–independent manner.

Bottom Line: To test for differences in the B cell response to intracellular and extracellular self-antigens, we sequestered a tolerogenic cell surface antigen intracellularly by addition of a two amino acid endoplasmic reticulum (ER) retention signal.In contrast to cell surface antigen, which causes the deletion of autoreactive B cells, the intracellularly sequestered self-antigen failed to induce B cell tolerance and was instead autoimmunogenic.The intracellular antigen positively selected antigen-binding B cells to differentiate into B1 cells and induced large numbers of IgM autoantibody-secreting plasma cells in a T-independent manner.

View Article: PubMed Central - PubMed

Affiliation: Nuffield Department of Clinical Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK.

ABSTRACT
Systemic autoimmune disease is frequently characterized by the production of autoantibodies against widely expressed intracellular self-antigens, whereas B cell tolerance to ubiquitous and highly expressed extracellular antigens is strictly enforced. To test for differences in the B cell response to intracellular and extracellular self-antigens, we sequestered a tolerogenic cell surface antigen intracellularly by addition of a two amino acid endoplasmic reticulum (ER) retention signal. In contrast to cell surface antigen, which causes the deletion of autoreactive B cells, the intracellularly sequestered self-antigen failed to induce B cell tolerance and was instead autoimmunogenic. The intracellular antigen positively selected antigen-binding B cells to differentiate into B1 cells and induced large numbers of IgM autoantibody-secreting plasma cells in a T-independent manner. By analyzing the impact of differences in subcellular distribution independently from other variables, such as B cell receptor affinity, antigen type, or tissue distribution, we have established that intracellular localization of autoantigen predisposes for autoantibody production. These findings help explain why intracellular antigens are targeted in systemic autoimmune diseases.

Show MeSH
Related in: MedlinePlus