title: Identification and characterization of immunoreactive calcitonin gene-related peptide from lymphocytes of the rat.
abstract: There is accumulating evidence that the immune system can produce neuropeptides. In the light of these facts, we obtained direct evidences to prove that T lymphocytes also synthesize and secrete calcitonin gene-related peptide (CGRP), a neuropeptide localized within primary sensory nerves. By using CGRP specific RIA, CGRP-like immunoreactivity (LI) was found in the extracts of rat lymphocytes from thymus and mesenteric lymph node. The intracellular concentration of lymphocyte-derived CGRP-LI of rat thymus and mesenteric lymph node was 745+/-39 and 447+/-33 fg/10(6) cells, respectively. CGRP-LI in lymphocytes was shown to co-elute with synthetic rat CGRP and sensory neuron-derived CGRP by reverse-phase HPLC. In addition, the CGRP-LI located in the T lymphocytes was also shown by immunocytochemical method examined by electron microscopy. The CGRP mRNA detected by RT-PCR was also present in these lymphocytes and was also identified to be the same one in sensory neurons. These data suggest that CGRP is synthesized and secreted in T lymphocytes of both thymus and lymph node in the rat, and this is identified to be the same one in neuronal tissue. Lymphocyte-derived CGRP may act in an autocrine/paracrine mode and play an important role in certain physiological and pathophysiological conditions.
authors.affiliation: Institute of Vascular Medicine, The Third Hospital, Beijing Medical University, China. xwang@mail.bjmu.edu.cn
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: L
authors.initials: L
authors.lastname: Xing
authors.forename: Y
authors.initials: Y
authors.lastname: Xing
authors.forename: Y
authors.initials: Y
authors.lastname: Tang
authors.forename: C
authors.initials: C
authors.lastname: Han
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D002851:Chromatography, High Pressure Liquid; D017931:DNA Primers; D005727:Ganglia, Spinal / Q000166:cytology / Q000276:immunology; D015870:Gene Expression / Q000276:immunology; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D008297:Male; D015213:Neuroimmunomodulation / Q000276:immunology*; D012333:RNA, Messenger / Q000032:analysis; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D013601:T-Lymphocytes / Q000737:chemistry* / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D015740:Calcitonin Gene-Related Peptide