PMID- 23772226 OWN - NLM STAT- PubMed-not-MEDLINE DCOM- 20130618 LR - 20211021 IS - 1664-3224 (Print) IS - 1664-3224 (Electronic) IS - 1664-3224 (Linking) VI - 4 DP - 2013 TI - The dendritic cell response to classic, emerging, and homeostatic danger signals. Implications for autoimmunity. PG - 138 LID - 10.3389/fimmu.2013.00138 [doi] LID - 138 AB - Dendritic cells (DCs) initiate and control immune responses, participate in the maintenance of immunological tolerance and are pivotal players in the pathogenesis of autoimmunity. In patients with autoimmune disease and in experimental animal models of autoimmunity, DCs show abnormalities in both numbers and activation state, expressing immunogenic levels of costimulatory molecules and pro-inflammatory cytokines. Exogenous and endogenous danger signals activate DCs to stimulate the immune response. Classic endogenous danger signals are released, activated, or secreted by host cells and tissues experiencing stress, damage, and non-physiologic cell death; and are therefore referred to as damage-associated molecular patterns (DAMPs). Some DAMPs are released from cells, where they are normally sequestered, during necrosis (e.g., heat shock proteins, uric acid, ATP, HMGB1, mitochondria-derived molecules). Others are actively secreted, like Type I Interferons. Here we discuss important DAMPs in the context of autoimmunity. For some, there is a clear pathogenic link (e.g., nucleic acids and lupus). For others, there is less evidence. Additionally, we explore emerging danger signals. These include inorganic materials and man-made technologies (e.g., nanomaterials) developed as novel therapeutic approaches. Some nanomaterials can activate DCs and may trigger unintended inflammatory responses. Finally, we will review "homeostatic danger signals," danger signals that do not derive directly from pathogens or dying cells but are associated with perturbations of tissue/cell homeostasis and may signal pathological stress. These signals, like acidosis, hypoxia, and changes in osmolarity, also play a role in inflammation and autoimmunity. FAU - Gallo, Paul M AU - Gallo PM AD - Laboratory of Dendritic Cell Biology, Department of Microbiology and Immunology, Temple Autoimmunity Center, Temple University School of Medicine , Philadelphia, PA , USA. FAU - Gallucci, Stefania AU - Gallucci S LA - eng PT - Journal Article DEP - 20130610 PL - Switzerland TA - Front Immunol JT - Frontiers in immunology JID - 101560960 PMC - PMC3677085 OTO - NOTNLM OT - DAMPs OT - acidosis OT - autoimmunity OT - dendritic cells OT - hypoxia OT - mitochondria OT - nanomaterial OT - osmolarity EDAT- 2013/06/19 06:00 MHDA- 2013/06/19 06:01 PMCR- 2013/01/01 CRDT- 2013/06/18 06:00 PHST- 2013/02/28 00:00 [received] PHST- 2013/05/23 00:00 [accepted] PHST- 2013/06/18 06:00 [entrez] PHST- 2013/06/19 06:00 [pubmed] PHST- 2013/06/19 06:01 [medline] PHST- 2013/01/01 00:00 [pmc-release] AID - 10.3389/fimmu.2013.00138 [doi] PST - epublish SO - Front Immunol. 2013 Jun 10;4:138. doi: 10.3389/fimmu.2013.00138. eCollection 2013.