Structure, Function, and Therapeutic Use of IgM Antibodies

Area of Science:

• Immunology
• Molecular Biology
• Biochemistry

Background:

• Natural immunoglobulin M (IgM) antibodies are ancient, conserved macro-immunoglobulins.
• They are the first antibodies produced during B cell development and upon antigen exposure.
• IgMs function as pentamers or hexamers with multiple antigen-binding sites.

Purpose of the Study:

• To review the biology, structure, function, and therapeutic potential of IgM antibodies.
• To highlight advancements in understanding IgM since its discovery.
• To discuss the therapeutic applications of natural and engineered IgM.

Main Methods:

• Review of existing literature on IgM antibody structure and function.
• Analysis of IgM's role in immune response and complement activation.
• Examination of clinical trial data for IgM-based therapeutics.

Main Results:

• IgM's polyvalency enables high avidity binding, effective against low-level and non-protein antigens.
• The joining (J) chain stabilizes IgM and facilitates receptor binding, including polymeric immunoglobulin receptor (pIgR) for mucosal transport.
• Natural IgM antibodies are being explored as therapeutics, with engineered variants showing promise.

Conclusions:

• IgM antibodies possess unique structural and functional properties advantageous for therapeutic development.
• Further research into IgM biology and engineering holds significant potential for novel treatments.
• IgM's role in innate and adaptive immunity is critical and warrants continued investigation.