Abnormal monoclonal plasma cells are an abnormal increase in plasma cells in the body. 1. Plasma cells are part of the body’s immune system and are produced by lymphoid B cells. Plasma cells are able to produce antibodies for defense, targeting against viral or bacterial infections. 2. Monoclonal is the body’s cells that have lost the ability to differentiate and mature to varying degrees and exhibit relatively unlimited growth. 3. Abnormal monoclonal plasma cells proliferate excessively and can produce large amounts of antibody-like substances, but these antibody-like substances are abnormal and therefore do not help the body to defend itself against infection. In addition, the number of normal antibodies usually decreases, making the body more susceptible to infection. 4. Abnormal monoclonal plasma cells producing a large number of abnormal antibodies usually do not cause obvious clinical manifestations, but if the abnormality lasts for a long time and the corresponding symptoms appear, which can be seen in multiple myeloma, etc., please consult a doctor in time and follow the doctor’s instructions to carry out standardized treatment.