November 8, 2023
Plasma cells are a type of white blood cell (WBC) and part of the body’s immune system. They are part of a group of immune cells called lymphocytes. Plasma cells produce proteins called immunoglobulins (also known as antibodies) that protect our body by sticking to bacteria and viruses. Antibodies can also stick to abnormal cells or cells that have stopped functioning normally.
When examined under a microscope these cells are small round cells. The cytoplasm (body) of the cell looks pink and the genetic material inside the nucleus is pushed to the edge of the cell. Pathologists use the word eccentric to describe a nucleus that sits at the edge of the cell.
Pathologists use a special test called immunohistochemistry to help them see these cells under the microscope. When this test is performed plasma cells produce a protein called CD138. These cells also produce immunoglobulins called kappa and lambda.
When examined under the microscope, groups of plasma cells can be seen during an infection or after an injury. Increased numbers of these cells can also be seen in certain medical conditions such as inflammatory bowel disease. Pathologists use the word plasmacytosis to describe the increased number of these cells seen in these conditions.
This article was written by doctors to help you read and understand your pathology report. Contact us if you have questions about this article or your pathology report. For a complete introduction to your pathology report, read this article.