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Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
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Janus kinases in immune cell signaling
Kamran Ghoreschi1, Arian Laurence, John J O'Shea
1Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA. ghoreschik@mail.nih.gov
Immunological Reviews
|March 18, 2009
Summary
Janus kinases (Jaks) are crucial for immune cell function and implicated in various diseases. Inhibitors targeting Jaks show promise for treating autoimmune disorders and malignancies, with numerous clinical trials underway.
Area of Science:
- Biochemistry
- Immunology
- Molecular Biology
Background:
- Janus kinases (Jaks) are non-receptor protein tyrosine kinases vital for cell signaling.
- They play critical roles in immune cell and hematopoietic cell growth, survival, development, and differentiation.
- Jak signaling pathways mediate crucial events in both innate and adaptive immunity.
Purpose of the Study:
- To review the role of Janus kinases (Jaks) in cellular processes and immunity.
- To discuss the implications of Jak deficiencies and mutations in human diseases.
- To highlight the therapeutic potential of selective Jak inhibitors in treating malignancies and autoimmune diseases.
Main Methods:
- Review of experimental mouse data and clinical observations.
- Analysis of genetic mutations and their associated clinical phenotypes.
- Examination of existing knowledge on Jak signaling pathways, biochemical structure, and intracellular interactions.
Main Results:
- Jak3 deficiency leads to severe combined immunodeficiency syndrome.
- Tyk2 mutations cause autosomal recessive hyperimmunoglobulin E syndrome.
- Activating mutations in Jaks, particularly Jak2, are associated with myeloproliferative disorders like polycythemia vera.
- Complete deletion of Jak1 or Jak2 is not compatible with life in mice.
Conclusions:
- Selective Jak inhibitors represent a promising therapeutic strategy for autoimmune diseases and malignancies.
- The development of Jak inhibitors is advancing rapidly, with 20 clinical trials currently investigating their safety and efficacy.
- Further research into Jak signaling pathways may unlock new treatment avenues.
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