Limits...
Autoimmune and infectious skin diseases that target desmogleins.

Amagai M - Proc. Jpn. Acad., Ser. B, Phys. Biol. Sci. (2010)

Bottom Line: Dsg2 is expressed in all tissues possessing desmosomes, including simple epithelia and myocardia, and mutations in this gene are responsible for arrhythmogenic right ventricular cardiomyopathy/dysplasia.Dsg4 plays an important adhesive role mainly in hair follicles, and Dsg4 mutations cause abnormal hair development.Further investigation of desmoglein molecules will continue to provide insight into the unsolved pathophysiological mechanisms of diseases and aid in the development of novel therapeutic strategies with minimal side effects.

View Article: PubMed Central - PubMed

Affiliation: Department of Dermatology, Keio University School of Medicine, Tokyo, Japan. amagai@sc.itc.keio.ac.jp

ABSTRACT
Desmosomes are intercellular adhesive junctions of epithelial cells that contain two major transmembrane components, the desmogleins (Dsg) and desmocollins (Dsc), which are cadherin-type cell-cell adhesion molecules and are anchored to intermediate filaments of keratin through interactions with plakoglobin and desmoplakin. Desmosomes play an important role in maintaining the proper structure and barrier function of the epidermis and mucous epithelia. Four Dsg isoforms have been identified to date, Dsg1-Dsg4, and are involved in several skin and heart diseases. Dsg1 and Dsg3 are the two major Dsg isoforms in the skin and mucous membranes, and are targeted by IgG autoantibodies in pemphigus, an autoimmune disease of the skin and mucous membranes. Dsg1 is also targeted by exfoliative toxin (ET) released by Staphylococcus aureus in the infectious skin diseases bullous impetigo and staphylococcal scalded skin syndrome (SSSS). ET is a unique serine protease that shows lock and key specificity to Dsg1. Dsg2 is expressed in all tissues possessing desmosomes, including simple epithelia and myocardia, and mutations in this gene are responsible for arrhythmogenic right ventricular cardiomyopathy/dysplasia. Dsg4 plays an important adhesive role mainly in hair follicles, and Dsg4 mutations cause abnormal hair development. Recently, an active disease model for pemphigus was generated by a unique approach using autoantigen-deficient mice that do not acquire tolerance against the defective autoantigen. Adoptive transfer of Dsg3(-/-) lymphocytes into mice expressing Dsg3 induces stable anti-Dsg3 IgG production with development of the pemphigus phenotype. This mouse model is a valuable tool with which to investigate immunological mechanisms of harmful IgG autoantibody production in pemphigus. Further investigation of desmoglein molecules will continue to provide insight into the unsolved pathophysiological mechanisms of diseases and aid in the development of novel therapeutic strategies with minimal side effects.

Show MeSH

Related in: MedlinePlus

Methods to develop an active disease mouse model for pemphigus vulgaris. In the conventional approach (A), various strains of wild-type mice are repeatedly immunized with recombinant Dsg3 (rDsg3) in various adjuvants to break their immunological tolerance. None of the immunized mice developed IgG that could bind to the native Dsg3 in vivo and showed no IgG deposition on keratinocyte cell surfaces in the skin. In a novel approach (B), splenocytes of Dsg3−/− mice, which do not acquire tolerance against Dsg3, were adoptively transferred into immunodeficient mice expressing Dsg3. Recipient mice persistently produced anti-Dsg3 IgG and developed the pemphigus vulgaris phenotype.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3108298&req=5

fig06: Methods to develop an active disease mouse model for pemphigus vulgaris. In the conventional approach (A), various strains of wild-type mice are repeatedly immunized with recombinant Dsg3 (rDsg3) in various adjuvants to break their immunological tolerance. None of the immunized mice developed IgG that could bind to the native Dsg3 in vivo and showed no IgG deposition on keratinocyte cell surfaces in the skin. In a novel approach (B), splenocytes of Dsg3−/− mice, which do not acquire tolerance against Dsg3, were adoptively transferred into immunodeficient mice expressing Dsg3. Recipient mice persistently produced anti-Dsg3 IgG and developed the pemphigus vulgaris phenotype.

Mentions: To investigate the pathophysiological mechanisms and develop therapeutic strategies, animal disease models have played important roles in the study of various conditions, including autoimmune diseases. The conventional approach to develop an autoimmune mouse model is forced immunization of autoantigens in various strains of mice with various types of adjuvant (Fig. 6A). However, this approach is empirical and immune responses are largely dependent on the strain of mouse or type of adjuvant used. Furthermore, any autoimmune reaction in these mice may be transient, unlike that found in patients, and the immune system is systemically stimulated.


Autoimmune and infectious skin diseases that target desmogleins.

Amagai M - Proc. Jpn. Acad., Ser. B, Phys. Biol. Sci. (2010)

Methods to develop an active disease mouse model for pemphigus vulgaris. In the conventional approach (A), various strains of wild-type mice are repeatedly immunized with recombinant Dsg3 (rDsg3) in various adjuvants to break their immunological tolerance. None of the immunized mice developed IgG that could bind to the native Dsg3 in vivo and showed no IgG deposition on keratinocyte cell surfaces in the skin. In a novel approach (B), splenocytes of Dsg3−/− mice, which do not acquire tolerance against Dsg3, were adoptively transferred into immunodeficient mice expressing Dsg3. Recipient mice persistently produced anti-Dsg3 IgG and developed the pemphigus vulgaris phenotype.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3108298&req=5

fig06: Methods to develop an active disease mouse model for pemphigus vulgaris. In the conventional approach (A), various strains of wild-type mice are repeatedly immunized with recombinant Dsg3 (rDsg3) in various adjuvants to break their immunological tolerance. None of the immunized mice developed IgG that could bind to the native Dsg3 in vivo and showed no IgG deposition on keratinocyte cell surfaces in the skin. In a novel approach (B), splenocytes of Dsg3−/− mice, which do not acquire tolerance against Dsg3, were adoptively transferred into immunodeficient mice expressing Dsg3. Recipient mice persistently produced anti-Dsg3 IgG and developed the pemphigus vulgaris phenotype.
Mentions: To investigate the pathophysiological mechanisms and develop therapeutic strategies, animal disease models have played important roles in the study of various conditions, including autoimmune diseases. The conventional approach to develop an autoimmune mouse model is forced immunization of autoantigens in various strains of mice with various types of adjuvant (Fig. 6A). However, this approach is empirical and immune responses are largely dependent on the strain of mouse or type of adjuvant used. Furthermore, any autoimmune reaction in these mice may be transient, unlike that found in patients, and the immune system is systemically stimulated.

Bottom Line: Dsg2 is expressed in all tissues possessing desmosomes, including simple epithelia and myocardia, and mutations in this gene are responsible for arrhythmogenic right ventricular cardiomyopathy/dysplasia.Dsg4 plays an important adhesive role mainly in hair follicles, and Dsg4 mutations cause abnormal hair development.Further investigation of desmoglein molecules will continue to provide insight into the unsolved pathophysiological mechanisms of diseases and aid in the development of novel therapeutic strategies with minimal side effects.

View Article: PubMed Central - PubMed

Affiliation: Department of Dermatology, Keio University School of Medicine, Tokyo, Japan. amagai@sc.itc.keio.ac.jp

ABSTRACT
Desmosomes are intercellular adhesive junctions of epithelial cells that contain two major transmembrane components, the desmogleins (Dsg) and desmocollins (Dsc), which are cadherin-type cell-cell adhesion molecules and are anchored to intermediate filaments of keratin through interactions with plakoglobin and desmoplakin. Desmosomes play an important role in maintaining the proper structure and barrier function of the epidermis and mucous epithelia. Four Dsg isoforms have been identified to date, Dsg1-Dsg4, and are involved in several skin and heart diseases. Dsg1 and Dsg3 are the two major Dsg isoforms in the skin and mucous membranes, and are targeted by IgG autoantibodies in pemphigus, an autoimmune disease of the skin and mucous membranes. Dsg1 is also targeted by exfoliative toxin (ET) released by Staphylococcus aureus in the infectious skin diseases bullous impetigo and staphylococcal scalded skin syndrome (SSSS). ET is a unique serine protease that shows lock and key specificity to Dsg1. Dsg2 is expressed in all tissues possessing desmosomes, including simple epithelia and myocardia, and mutations in this gene are responsible for arrhythmogenic right ventricular cardiomyopathy/dysplasia. Dsg4 plays an important adhesive role mainly in hair follicles, and Dsg4 mutations cause abnormal hair development. Recently, an active disease model for pemphigus was generated by a unique approach using autoantigen-deficient mice that do not acquire tolerance against the defective autoantigen. Adoptive transfer of Dsg3(-/-) lymphocytes into mice expressing Dsg3 induces stable anti-Dsg3 IgG production with development of the pemphigus phenotype. This mouse model is a valuable tool with which to investigate immunological mechanisms of harmful IgG autoantibody production in pemphigus. Further investigation of desmoglein molecules will continue to provide insight into the unsolved pathophysiological mechanisms of diseases and aid in the development of novel therapeutic strategies with minimal side effects.

Show MeSH
Related in: MedlinePlus