Development of a sensitive ELISA for human

A new, sensitive ELISA for human leptin in plasma and cerebrospinal fluid (CSF) was developed, using mono-clonal antibodies. The lower limit of detection of this ELISA was 0.78 pg/assay. Both intra- and interassay imprecision values were <7%. The dilution curves of plasma and CSF showed good linearity, and the recov-ery was 83.2–95.6%. There was good correlation between plasma leptin concentrations by the ELISA and a com-mercially available RIA (r 5 0.99). Our ELISA is advan-tageous because it does not require radioisotopes, it produces results in hours rather than days, and more importantly, it improves on the detection limit and plasma interference of the RIA kit. The new ELISA enables measurement of low concentrations of leptin, as are seen in CSF and in plasma of patients with anorexi