Changes in serum immunoglobulin M (IgM) concentrations during early development of chum salmon ( Oncorhynchus keta) as determined by sensitive elisa technique

Abstract

1. 1. A specific and sensitive sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the measurement of low levels of serum immunoglobulin M (IgM) of chum salmon Oncorhynchus keta. 2. 2. In this assay, 5 μl serum was enough to measure the concentration of IgM and the minimum detectable concentration of serum IgM was about 5 ng/ml. 3. 3. Coefficients of variation within and between assays ranged from 2.90 to 9.61%. 4. 4. IgM concentrations remained at low level (< 300 ng/ml) until 40 days after hatching and then increased rapidly at the period of emergence (48 days after hatching).