Murphy Roths large

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Murphy Roths large (MRL/MpJ) is a strain of laboratory mouse developed in 1999 at The Wistar Institute in Philadelphia, PA. [1] Originally bred for autoimmune disease research, it was discovered to have remarkable tissue regeneration abilities. [2] [3] [4]



The MRL/MpJ mouse strain was selectively bred by scientists to have an autoimmune genetic disorder (retained through inbreeding) to be used as a model for autoimmune disease research. [1] After making puncture wounds in their ears, these mice were observed to completely regenerate from these wounds without development of scar tissue. [1] [2] In further research, this mouse strain has been observed to have the ability to also regenerate cardiac tissue, displays a resistance to muscle dystrophy, and is resistant to experiencing hyperglycemia from a diet high in fats. [5] [6] [7]

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Eosinophil variety of white blood cell

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Laboratory mouse animal used in labs

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Ellen Heber-Katz American biologist

Ellen Heber-Katz is an American immunologist/regeneration biologist who is professor at Lankenau Institute for Medical Research (LIMR). She is an immunologist who investigates mammalian regeneration, having discovered the ability of the MRL mouse strain to regenerate wounds without scarring and to fully restore damaged tissues. Her work on regeneration has been extended into National Cancer Institute (NCI)-funded studies of novel aspects of breast cancer causation. Her research interests include immunology, regenerative medicine and cancer.

Originally identified as Kirsten ras associated gene (krag), Sarcospan (SSPN) (is a 25-kDa transmembrane protein located in the dystrophin-associated protein complex of skeletal muscle cells, where it is most abundant. It contains four transmembrane spanning helices with both N- and C-terminal domains located intracellularly. Loss of SSPN expression occurs in patients with Duchenne muscular dystrophy. Dystrophin is required for proper localization of SSPN. SSPN is also an essential regulator of Akt signaling pathways. Without SSPN, Akt signaling pathways will be hindered and muscle regeneration will not occur.

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Earmark (agriculture)

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Kanneboyina Nagaraju is a medical scientist and immunologist who is credited with creating the MHC Class I transgenic mouse model for autoimmune myositis. Nagaraju is also credited with identifying novel glucocorticoid analogs with reduced side effect profiles in collaboration with Eric Hoffman and John McCall. He led international efforts to improve rigor and reproducibility of preclinical drug trials and phenotyping in neuromuscular disease models.

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  1. 1 2 3 Clark, Lise Desquenne; Clark, Robert K.; Heber-Katz, Ellen (July 1998). "A New Murine Model for Mammalian Wound Repair and Regeneration". Clinical Immunology and Immunopathology. 88 (1): 35–45. doi:10.1006/clin.1998.4519. ISSN   0090-1229. PMID   9683548.
  2. 1 2 Heber-Katz, E.; Leferovich, J. M.; Bedelbaeva, K.; Gourevitch, D. (2004). "Spallanzani's mouse: a model of restoration and regeneration". Current Topics in Microbiology and Immunology. 280: 165–89. doi:10.1007/978-3-642-18846-6_5. ISBN   978-3-642-62321-9. PMID   14594211.
  3. Morelle, Rebecca (11 April 2006). "Mouse sheds light on regeneration". BBC News .
  4. Carswell, Lindsay (18 April 2006). "Self-healing Mice". ScienCentral News. Archived from the original on 20 October 2008.
  5. Heber-Katz, Ellen; Leferovich, John M.; Bedelbaeva, Khamilia (2001-12-01). "Spontaneous heart regeneration in adult MRL mice after cryoinjury". Gene Therapy and Regulation. 1 (4): 399–407. doi:10.1163/156855801760107055. ISSN   1568-5586.
  6. Heydemann, Ahlke; Swaggart, Kayleigh; Kim, Gene H; Holley-Cuthrell, Jenan; Hadhazy, Michele; McNally, Elizabeth M (2012). "The superhealing MRL background improves muscular dystrophy". Skeletal Muscle. 2 (1): 26. doi: 10.1186/2044-5040-2-26 . ISSN   2044-5040. PMID   23216833.
  7. Mull, Aaron J.; Berhanu, Tirsit K.; Roberts, Nathan W.; Heydemann, Ahlke (December 2014). "The Murphy Roths Large (MRL) mouse strain is naturally resistant to high fat diet-induced hyperglycemia". Metabolism. 63 (12): 1577–1586. doi:10.1016/j.metabol.2014.09.007. ISSN   0026-0495. PMC   4252560 . PMID   25308446.