title: Measurement of CGRP in dried blood spots using a modified sandwich enzyme immunoassay.
abstract: Calcitonin gene-related peptide (CGRP) has roles as a neurotransmitter, neuromodulator and trophic factor. CGRP has been reported to be elevated in neonatal blood of children with autism or mental retardation as compared with normal subjects by recycling immuno-affinity chromatography (RIC). While CGRP detection in neonatal blood is thus important, it is not easy to detect CGRP in dried blood spots because of the limitations of sample volume and the specificity and the sensitivity of available assay systems. In the present study, we modified a "Sandwich Enzyme Immunoassay" for the purpose of detecting CGRP in blood spot eluate. We have prepared blood spots from blood collected from normal human subjects and measured CGRP level in eluates from these blood spots. Instead of a purification step, we have introduced a pre-incubation step and used washed erythrocytes as a dilution solution. The modified assay has good recovery and specificity and appropriate dilution curves. We have compared the eluate levels with levels in serum and plasma from the same individuals and find that CGRP levels in blood spot eluate were similar to those of serum and plasma. Thus, the newly modified EIA may be a useful method for the detection of CGRP in blood spot eluate.
authors.affiliation: Laboratory of Cell Biology, Korea Research Institute of Bioscience and Biotechnology, Yusong, Daejeon 305-600, Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Song
authors.forename: Cassandra
authors.initials: C
authors.lastname: Vandunk
authors.forename: Thea
authors.initials: T
authors.lastname: Kuddo
authors.forename: Phillip G
authors.initials: PG
authors.lastname: Nelson
mesh_terms: D000918:Antibody Specificity / Q000276:immunology; D001321:Autistic Disorder / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology; D001774:Blood Chemical Analysis / Q000379:methods*; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis* / Q000097:blood*; D004912:Erythrocytes / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods* / Q000639:trends; D008607:Intellectual Disability / Q000175:diagnosis / Q000378:metabolism / Q000503:physiopathology; D010949:Plasma / Q000737:chemistry; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D044967:Serum / Q000737:chemistry; D012996:Solutions
chemical_list: D012996:Solutions; D015740:Calcitonin Gene-Related Peptide