Which of the following describes a murine monoclonal antibody?

A murine monoclonal antibody is derived entirely from mouse sources, meaning it is generated from mouse B cells. This type of antibody is fully murine, consisting entirely of mouse proteins. They are typically produced by fusing mouse myeloma cells with mouse spleen cells, resulting in hybridoma cells that produce antibodies against a specific antigen.

Murine monoclonal antibodies were some of the first types utilized in research and clinical applications, but they can elicit immune responses in human patients, leading to limitations in their use. The other options describe antibodies that contain varying percentages of human components, indicating they are not fully murine. For instance, humanized antibodies contain human protein sequences that reduce immune reaction in humans. Thus, understanding the full murine nature of a murine monoclonal antibody is crucial for differentiating it from other types of monoclonal antibodies that have been modified for use in humans.