Cytokine signatures in hereditary fever syndromes (HFS)

- The current review presents all available data regarding the cytokines' signatures in HFS at the transcriptional, serum and ex vivo levels.
- It also integrates recent data in an updated classification of the different HFS: CAPS, NLRP12AD, FMF, HIDS/MKD, TRAPS and TRAPS11.
- Cytokine signatures in patients' cells cultured ex vivo are much more convincing than results obtained at the transcriptional levels or in sera.
- Pro-inflammatory cytokines are involved in the inflammatory process of HFS, even during remission periods.
- The marked increase of IL-1β production by LPS-stimulated PBMCs observed in CAPS, NLRP12AD, FMF and MKD, is a hallmark of these disorders.

Hereditary fever syndromes (HFS) include a group of disorders characterized by recurrent self-limited episodes of fever accompanied by inflammatory manifestations occurring in the absence of infection or autoimmune reaction. Advances in the genetics of HFS have led to the identification of new gene families and pathways involved in the regulation of inflammation and innate immunity. The key role of several cytokine networks in the pathogenesis of HFS has been underlined by several groups, and supported by the rapid response of patients to targeted cytokine blocking therapies. This can be due to the direct effect of cytokine overproduction or to an absence of receptor antagonist resulting in dysbalance of downstream pro- and anti-inflammatory cytokine networks.The aim of this study was to present an overview and to discuss the major concepts regarding the cellular and molecular immunology of HFS, with a particular focus on their specific cytokine signatures and physiopathological implications. Based on their molecular and cellular mechanisms, HFS have been classified into intrinsic and extrinsic IL-1β activation disorders or inflammasomopathies, and protein misfolding disorders. This review integrates all recent data in an updated classification of HFS.