A novel class of somatic mutations in blood detected preferentially in CD8+ cells.
Clin Immunol
; 175: 75-81, 2017 02.
Article
em En
| MEDLINE
| ID: mdl-27932211
ABSTRACT
Somatic mutations have a central role in cancer but their role in other diseases such as autoimmune disorders is poorly understood. Earlier work has provided indirect evidence of rare somatic mutations in autoreactive T-lymphocytes in multiple sclerosis (MS) patients but such mutations have not been identified thus far. We analysed somatic mutations in blood in 16 patients with relapsing MS and 4 with other neurological autoimmune disease. To facilitate the detection of somatic mutations CD4+, CD8+, CD19+ and CD4-/CD8-/CD19- cell subpopulations were separated. We performed next-generation DNA sequencing targeting 986 immune-related genes. Somatic mutations were called by comparing the sequence data of each cell subpopulation to other subpopulations of the same patient and validated by amplicon sequencing. We found non-synonymous somatic mutations in 12 (60%) patients (10 MS, 1 myasthenia gravis, 1 narcolepsy). There were 27 mutations, all different and mostly novel (67%). They were discovered at subpopulation-wise allelic fractions of 0.2%-4.6% (median 0.95%). Multiple mutations were found in 8 patients. The mutations were enriched in CD8+ cells (85% of mutations). In follow-up after a median time of 2.3years, 96% of the mutations were still detectable. These results unravel a novel class of persistent somatic mutations, many of which were in genes that may play a role in autoimmunity (ATM, BTK, CD46, CD180, CLIP2, HMMR, IKFZF3, ITGB3, KIR3DL2, MAPK10, CD56/NCAM1, RBM6, RORA, RPA1 and STAT3). Whether some of this class of mutations plays a role in disease is currently unclear, but these results define an interesting hitherto unknown research target for future studies.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Linfócitos T CD8-Positivos
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Mutação
Limite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Clin Immunol
Assunto da revista:
ALERGIA E IMUNOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article