An enzyme-linked immunosorbent assay (ELISA) for quantification of human collectin 11 (CL-11, CL-K1).
Collectin 11 (CL-11), also referred to as collectin kidney 1 (CL-K1), is a pattern recognition molecule that belongs to the collectin group of proteins involved in innate immunity. It interacts with glycoconjugates on pathogen surfaces and has been found in complex with mannose-binding lectin-associated serine protease 1 (MASP-1) and/or MASP-3 in circulation. Mutation in the CL-11 gene was recently associated with the developmental syndrome 3MC. In the present study, we established and thoroughly validated a sandwich enzyme-linked immunosorbent assay (ELISA) based on two different monoclonal antibodies. The assay is highly sensitive, specific and shows excellent quantitative characteristics such as reproducibility, dilution linearity and recovery (97.7-104%). The working range is 0.15-34 ng/ml. The CL-11 concentration in two CL-11-deficient individuals affected by the 3MC syndrome was determined to be below 2.1 ng/ml. We measured the mean serum CL-11 concentration to 284 ng/ml in 100 Danish blood donors, with a 95% confidence interval of 269-299 ng/ml. There was no significant difference in the CL-11 concentration measured in matched serum and plasma samples. Storage of samples and repeated freezing and thawing to a certain extent did not influence the ELISA. This ELISA offers a convenient and reliable method for studying CL-11 levels in relation to a variety of human diseases and syndromes.
Department of Cancer and Inflammation Research, Institute of Molecular Medicine, University of Southern Denmark, Winslowparken 21-1, DK-5000 Odense, Denmark.
L
L
Selman
M L
ML
Henriksen
J
J
Brandt
Y
Y
Palarasah
A
A
Waters
P L
PL
Beales
U
U
Holmskov
T J D
TJ
Jørgensen
C
C
Nielsen
K
K
Skjodt
S
S
Hansen
D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry; D016466:CHO Cells; D002478:Cells, Cultured; D037222:Collectins / Q000097:blood*; D006224:Cricetinae; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000911:Antibodies, Monoclonal; C518521:Colec11 protein, human; D037222:Collectins