Calcitonin gene-related peptide regulates type IV hypersensitivity through dendritic cell functions

• Published in: PloS one 2014-01, Vol.9 (1), p.e86367-e86367
• Main Authors: Mikami, Norihisa, Sueda, Kaori, Ogitani, Yusuke, Otani, Ippei, Takatsuji, Miku, Wada, Yasuko, Watanabe, Keiko, Yoshikawa, Rintaro, Nishioka, Satoshi, Hashimoto, Nagisa, Miyagi, Yayoi, Fukada, So-ichiro, Yamamoto, Hiroshi, Tsujikawa, Kazutake
• Format: Article
• Language: English
• Subjects: Adaptive immunity; Adaptive systems; Albumin; Allergy; Animals; Antigen presentation; B7-1 Antigen - immunology; Biology; Calcitonin; Calcitonin gene-related peptide; Calcitonin Gene-Related Peptide - immunology; CC chemokine receptors; CCR2 protein; CD80 antigen; Cell culture; Cell differentiation; Cell Differentiation - immunology; Chemokine CCL2 - immunology; Chemokine receptors; Chemokines; Cytokines; Dendritic cells; Dendritic Cells - immunology; Differentiation (biology); Down-Regulation - immunology; Drainage; Genes; Hypersensitivity; Hypersensitivity (delayed); Hypersensitivity, Delayed - immunology; Immune response; Immune system; Immunity; Immunization; Immunology; Inflammation; Innate immunity; Interleukin 12; Interleukin-12 - immunology; Laboratories; Lipopolysaccharides; Lymph nodes; Lymphocytes T; Medicine; Mice; Mice, Inbred BALB C; Mitogens; Monocyte chemoattractant protein 1; Monocyte Chemoattractant Proteins - immunology; Nervous system; Neuropeptides; Ovalbumin; Peptides; Pharmaceutical sciences; Physiology; Proteins; Receptor activity modifying proteins; Receptor Activity-Modifying Protein 1 - immunology; Receptors; Receptors, CCR2 - immunology; Rodents; Th1 Cells - immunology; TNF inhibitors
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0086367

Dendritic cells (DCs) play essential roles in both innate and adaptive immune responses. In addition, mutual regulation of the nervous system and immune system is well studied. One of neuropeptides, calcitonin gene-related peptide (CGRP), is a potent regulator in immune responses; in particular, it has anti-inflammatory effects in innate immunity. For instance, a deficiency of the CGRP receptor component RAMP 1 (receptor activity-modifying protein 1) results in higher cytokine production in response to LPS (lipopolysaccharide). On the other hand, how CGRP affects DCs in adaptive immunity is largely unknown. In this study, we show that CGRP suppressed Th1 cell differentiation via inhibition of IL-12 production in DCs using an in vitro co-culture system and an in vivo ovalbumin-induced delayed-type hypersensitivity (DTH) model. CGRP also down-regulated the expressions of chemokine receptor CCR2 and its ligands CCL2 and CCL12 in DCs. Intriguingly, the frequency of migrating CCR2(+) DCs in draining lymph nodes of RAMP1-deficient mice was higher after DTH immunization. Moreover, these CCR2(+) DCs highly expressed IL-12 and CD80, resulting in more effective induction of Th1 differentiation compared with CCR2(-) DCs. These results indicate that CGRP regulates Th1 type reactions by regulating expression of cytokines, chemokines, and chemokine receptors in DCs.