A sensitive enzyme-linked immunosorbent assay for dihydrofolate reductase

Area of Science:

• Biochemistry
• Enzymology
• Immunochemistry

Background:

• Dihydrofolate reductase (DHFR) is a critical enzyme in folate metabolism.
• Accurate quantification of DHFR is essential for understanding its role in various biological processes and diseases.
• Existing methods like radioimmunoassay (RIA) have limitations in sensitivity or accessibility.

Purpose of the Study:

• To develop and validate a sensitive and specific competitive enzyme-linked immunosorbent assay (ELISA) for dihydrofolate reductase (DHFR).
• To compare the performance of the developed ELISA with existing methods for DHFR quantification.
• To establish a reliable method for measuring both functional and non-functional immunoreactive forms of DHFR.

Main Methods:

• Development of a competitive enzyme-linked immunosorbent assay (ELISA) for dihydrofolate reductase (DHFR).
• Validation of the assay's sensitivity, specificity, and precision.
• Comparison of ELISA results with [3H]-methotrexate binding assays and radioimmunoassay (RIA).

Main Results:

• The developed ELISA demonstrated a sensitivity of approximately 3 ng of immunoreactive enzyme protein.
• Assay precision showed a mean coefficient of variation of less than 13% for both within- and between-assay measurements.
• The ELISA results were comparable to [3H]-methotrexate binding assays, indicating specificity and validity.

Conclusions:

• A sensitive and specific competitive ELISA for dihydrofolate reductase (DHFR) has been successfully developed.
• This ELISA method offers comparable sensitivity to RIA and provides valid measurements of enzyme concentration.
• The assay is valuable for quantifying both functional and non-functional immunoreactive DHFR, aiding in research and diagnostics.