A dot-blot method for screening polyclonal and monoclonal antisera to poly(ADP-ribose)

Area of Science:

• Biochemistry
• Molecular Biology
• Immunology

Background:

• ADP-ribosylation is crucial for cellular regulation and DNA damage repair.
• Antibodies to poly(ADP-ribose) (PAR) are valuable probes for studying these processes.
• Existing methods for antibody detection can be complex or require highly purified reagents.

Purpose of the Study:

• To develop a simple, sensitive dot-blot assay for detecting and titrating antibodies to PAR.
• To utilize radiolabeled PAR as a probe for antibody detection with minimal background.
• To apply this method for screening SLE patient sera and quantifying ADP-ribosylated proteins.

Main Methods:

• Nitrocellulose membranes (NC) were used as a support for dot-blot analysis.
• A highly labeled PAR preparation was generated using 32P-NAD and calf thymus nuclear extract.
• The labeled PAR served as a reagent to detect anti-PAR antibody spots on NC.

Main Results:

• The dot-blot assay demonstrated high sensitivity and low background for anti-PAR antibody detection.
• The method allowed for titration and semi-quantitative evaluation of antisera.
• The assay was successfully applied to screen SLE patient sera and quantify ADP-ribosylated proteins in tumor cells.

Conclusions:

• A simple, sensitive, and versatile dot-blot assay for anti-PAR antibodies was established.
• This method facilitates research in DNA repair and cellular regulation.
• The assay has potential applications in clinical diagnostics and cancer research.