What are the types of monoclonal antibodies based on their functions?

Based on their function, monoclonal antibodies can be classified as neutralizing antibodies, immune checkpoint inhibitors, and antibody-drug conjugates.

1. mAbs can neutralize activity of pathogens by binding to their functional sites. This prevents the pathogen from interacting with host cells and causing infection. They do this by blocking the interaction between the pathogen and its cellular receptor. 
2. These antibodies can also be immune checkpoint inhibitors, which target molecules that regulate the immune response such as PD-1, and CTLA-4. The blocking of these checkpoints enhances the immune response against cancer by simultaneously promoting activation and proliferation of T cells, reduces regulatory T cell function, and enhances the killing of tumor cells by cytotoxic T lymphocytes. 
3. Antibody drug-conjugates have drugs or radioactive agents attached to them. The mAb then finds the cancer cells and delivers the drug or radioactive agent directly to them. The drug is typically a potent chemotherapy agent that is released upon binding of the antibody to the target cell. All approved therapeutic mAbs are IgG (most are IgG1) and have been well-characterized for effector functions.