Microarray-based gene expression profiling in patients with cryopyrin-associated periodic syndromes defines a disease-related signature and IL-1-responsive transcripts
- James E Balow Jr1,
- John G Ryan1,
- Jae Jin Chae1,
- Matthew G Booty1,
- Ariel Bulua2,
- Deborah Stone1,
- Hong-Wei Sun3,
- James Greene4,
- Beverly Barham1,
- Raphaela Goldbach-Mansky5,
- Daniel L Kastner1,
- Ivona Aksentijevich1
- 1Inflammatory Disease Section, National Human Genome Research Institute (NHGRI), Bethesda, Maryland, USA
- 2Immunoregulation Unit, Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), Bethesda, Maryland, USA
- 3Office of Science and Technology, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), Bethesda, Maryland, USA
- 4The Catholic University of America, Washington, DC, USA
- 5Translational Autoinflammatory Disease Section, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), Bethesda, Maryland, USA
- Correspondence to Dr Ivona Aksentijevich, National Human Genome Research Institute (NHGRI), 9000 Rockville Pike, Bldg.10/B2-5235, Bethesda, MD 20892-1820, USA;
- Accepted 23 September 2012
- Published Online First 5 December 2012
Objective To analyse gene expression patterns and to define a specific gene expression signature in patients with the severe end of the spectrum of cryopyrin-associated periodic syndromes (CAPS). The molecular consequences of interleukin 1 inhibition were examined by comparing gene expression patterns in 16 CAPS patients before and after treatment with anakinra.
Methods We collected peripheral blood mononuclear cells from 22 CAPS patients with active disease and from 14 healthy children. Transcripts that passed stringent filtering criteria (p values ≤ false discovery rate 1%) were considered as differentially expressed genes (DEG). A set of DEG was validated by quantitative reverse transcription PCR and functional studies with primary cells from CAPS patients and healthy controls. We used 17 CAPS and 66 non-CAPS patient samples to create a set of gene expression models that differentiates CAPS patients from controls and from patients with other autoinflammatory conditions.
Results Many DEG include transcripts related to the regulation of innate and adaptive immune responses, oxidative stress, cell death, cell adhesion and motility. A set of gene expression-based models comprising the CAPS-specific gene expression signature correctly classified all 17 samples from an independent dataset. This classifier also correctly identified 15 of 16 post-anakinra CAPS samples despite the fact that these CAPS patients were in clinical remission.
Conclusions We identified a gene expression signature that clearly distinguished CAPS patients from controls. A number of DEG were in common with other systemic inflammatory diseases such as systemic onset juvenile idiopathic arthritis. The CAPS-specific gene expression classifiers also suggest incomplete suppression of inflammation at low doses of anakinra.