U937 cells are a widely used tool in biological and medical research. They offer a valuable model for understanding various cellular processes and disease mechanisms.
Origin and Identity of U937 Cells
U937 cells are a human cell line, specifically derived from a patient with histiocytic lymphoma, a type of cancer affecting immune cells. These cells were first isolated in 1974 from the pleural effusion of a 37-year-old Caucasian male with generalized histiocytic lymphoma by Sundstrom and Nilsson. They are classified as a pro-monocytic cell line, meaning they resemble immature monocytes, a type of white blood cell.
Unlike cells that grow attached to a surface, U937 cells are immortalized, allowing them to grow indefinitely in suspension cultures. This characteristic makes them a stable and convenient model for laboratory research. Their average diameter is approximately 14 micrometers, and they exhibit a round-shaped morphology.
Distinctive Characteristics for Research
U937 cells possess unique biological and functional attributes. A notable characteristic is their ability to differentiate into macrophage-like cells when stimulated with certain compounds, such as phorbol esters like phorbol 12-myristate 13-acetate (PMA). This differentiation process involves significant changes in their morphology, causing them to become adherent and develop pseudopodia, similar to mature macrophages.
Upon differentiation, U937 cells begin to express various monocyte/macrophage markers, including CD14, CD68, and HLA-DR, which are typical of myeloid cells. They also acquire functional properties such as phagocytosis and the production of reactive oxygen species (ROS). Beyond macrophages, U937 cells can also differentiate into dendritic cells or even osteoclasts, depending on the specific stimuli and culture conditions. This adaptability allows researchers to study different aspects of immune cell development and function.
Major Research Applications
U937 cells are utilized across several scientific disciplines. In immunology, they serve as a model for studying immune responses and inflammation, including the production and regulation of cytokines. Their monocyte-like features make them suitable for investigating immune responses to infections like the dengue virus.
In cancer biology, U937 cells are applied in leukemia research, particularly for acute myeloid leukemia (AML), and in screening potential anti-cancer drug candidates. These cells also find use in virology, especially in HIV research, as they are susceptible to infection, allowing scientists to study viral replication and latency. Furthermore, in toxicology and pharmacology, U937 cells are employed to assess the cellular responses to various compounds, including drugs and environmental pollutants.
Advancing Medical Knowledge
U937 cells have advanced our understanding of diseases and fundamental biological processes. They have provided insights into monocyte and macrophage differentiation, revealing the molecular basis of how these cells develop and acquire their functions. This has contributed to a deeper comprehension of immune cell development and their roles in health and disease.
Studies using U937 cells have also illuminated mechanisms of inflammation, including the complex regulation of inflammatory gene expression and the signaling pathways involved, such as the NF-κB pathway. In the context of leukemia, U937 cells have helped identify potential drug targets for acute myeloid leukemia, as they express mutations like JAK3M511I, which respond to specific inhibitors. Their susceptibility to viruses, such as influenza, has enabled the development of models for screening immunomodulatory and antiviral agents.