Double‐staining artefact observed in certain individuals during dual‐colour immunophenotyping of lymphocytes by flow cytometry

Open Access
Publisher Website
Google Scholar
Abstract
An unusual double‐staining artefact has been repeatedly observed in certain individuals (both HIV‐positive and healthy laboratory controls) during 2‐colour immunophenotyping of lymphocytes by flow cytometry after red cell lysis. This artefact can falsely suggest co‐expression of CD4 and CD8, as well as some of the other monoclonal antibody pairs commonly used in the typing of lymphocytes. It is caused by a serum factor associated with the ammonium‐sulphate‐precipitated and gamma‐globulin fractions. It appears to be fairly common in the population (being found in 6 out of 105 of our healthy laboratory controls and in 42 out of 247 of our HIV‐1 seropositive subjects); it may be genetically determined, but may be acquired in some. It is a potential source of error in lymphocyte immunophenotyping, which can be avoided by simple adjustments to the recommended techniques.