U937 Cells - a Model for Monocytic Leukemia Research and Progress
The U937 cell line, a widely utilized in vitro model in biomedical research, is derived from a pro-monocytic lineage, offering valuable insights into the cellular dynamics of myeloid cells. This article delves into the origin, general characteristics, and diverse applications of the U937 cell line, which is integral to understanding the molecular mechanisms and signaling pathways in immune cells, particularly in the context of acute myeloid leukemia (AML).
Origin and General Characteristics of the U937 Cells
This segment will illuminate the genesis and fundamental traits of the U937 cell line. You'll discover the essence of the U937 leukemia cell line, its cellular identity, its derivation, and the key characteristics that make it a pivotal model in research.
U937 cells, established from the pleural effusion of a 37-year-old Caucasian male with generalized histiocytic lymphoma by Sundstrom and Nilsson in 1976, represent a unique pro-monocytic phenotype [1]. These cells embody the morphology typical of monocyte-macrophage cell types, with round-shaped structures and an average diameter of about 14 μm, featuring surface markers like the human DC-SIGN protein, which is crucial for their role in immunological studies. The U937 cell line's differentiation capacity into various immune cells—including monocytes, macrophages, and even dendritic cells—upon exposure to certain stimuli is of significant interest, offering a dynamic system to explore cell differentiation processes.
The cellular repertoire of U937 also includes the ability to express amelogenin, a marker often studied in the context of circulatory precursor cells and the evaluation of abnormal chromosomes, particularly parts of chromosome 16, underpinning its status as a rich resource within the Cancer Cell Line Encyclopedia. Through techniques such as 3D cell culture and advanced imaging, U937 cells provide a near-vivo situation, allowing researchers to observe the cells' behavior and interactions in a more physiologically relevant environment.
U937 cell line: Culturing information
Knowing the following key point for culturing U937 cells can make your work easy and efficient with it. You will learn: What is the doubling time of U937 cells? Is the U937 cell line adherent or suspension? What is U937 media? How do you culture U937 cells?
Key Points for Culturing U937 Cells
|
Population Doubling Time: |
The average population doubling time of U937 cells is 36 hours. However, it may range between 48 and 72 hours. |
|
Adherent or in Suspension: |
U937 macrophages are round in shape and grow in suspension cultures. |
|
Seeding Density: |
1 x 105 cells/mL seeding density is recommended for U937 cells. No passaging solution is required for suspended cells. They are diluted with fresh medium and counted. The cells are seeded at the required cell density into a new flask. |
|
Growth Medium: |
U937 cell culture is maintained in RPMI 1640 medium. This medium is supplemented with 2.0 mM L-glutamine, 2.0 g/L NaHCO3, 2.0 g/L L-glucose, and 10% FBS for optimum cell growth. Media is replaced 1 to 2 times a week. |
|
Growth Conditions (Temperature, CO2): |
U937 cell cultures require a 37°C humidified incubator with a 5% CO2 supply for ideal growth. |
|
Storage: |
U937 cells are kept in the vapor phase of liquid nitrogen or at below -150°C temperature to maintain cell viability for longer terms. |
|
Freezing Process and Medium: |
CM-1 or CM-ACF freezing media is used for freezing human macrophage cell line U937. A slow freezing method (gradual 1°C drop in temperature) is recommended to protect maximum cell viability. |
|
Thawing Process: |
Frozen vials are kept in a 37°C water bath until a small ice clump is left. The cells are added with fresh media and centrifuged. Media is discarded and the cell pellet is resuspended and poured into a new flask. U937 cells exhibit a comparatively fast freezing recovery. |
|
Biosafety Level: |
Biosafety level 1 laboratory settings are recommended for U937 cell culturing. |
Advantages & disadvantages of U937 cells
U937 cells possess a unique mixture of pros and cons that make them an ideal research tool. The prominent advantages and disadvantages of U937 cell culture are discussed below.
Advantages
The main advantages of the U937 cell line include:
- Higher stability: U937 cell line exhibits high stability due to its histiocytic origin compared to primary blood leukemia cells. Moreover, these cells can be cultured indefinitely and are genetically homogeneous thus, serve as a convenient model for research studies.
- Differentiation: U937 cells have the ability to differentiate into other immune cells such as monocytes, macrophages, or dendritic cells when subjected to a stimulus. This helps in understanding the cellular mechanisms involved in generating immune responses.
- East to maintain: U937 cells are easy to culture and maintain in research laboratories. There are no complicated procedures or protocols to follow for culturing U937 cells.
Disadvantages
Here are some disadvantages associated with the U937 cell line.
- Chromosomal abnormalities: The U937 cells possess chromosomal aberrations including translocations. This may affect the experimental outcomes and reproducibility of results.
U937 Monocytic Cell Line for Immunological and Hematological Research
Applications of U937 cell line in research
U937 cells, a histiocytic lymphoma cell line, serve as an invaluable model for various biological research applications. They are particularly esteemed for their role in the study of myeloid cells, especially as macrophage models, due to their ability to differentiate into macrophage-like cells under certain conditions. The U937 cell line facilitates the examination of macrophage function, including phagocytic activity and the neurobiology of cytokines, which are crucial for understanding inflammatory responses and immune regulation. This cell line also exhibits properties similar to primary monocytes, which allows researchers to investigate the nuances of immune cell behavior without the variability present in primary cells.
- Cytogenetics: In the realm of cytogenetic characterization, U937 cells have been pivotal in studying chromosome 11 and parts of chromosomes 16, particularly regarding centromere capture and the behavior of homologous chromosomes. Researchers rely on these cells to investigate genome reorganization and genome instability, which are essential for understanding the fundamentals of cancer progression, including histiocytic lymphoma from which U937 cells are derived. The cell line provides accurate karyotype information, making it an excellent tool for studying abnormalities in chromosomes and rearranged chromosomes, especially those involving chromosome 20 rearrangements.
- Monocytes/Macrophages Biology: The U937 cell line serves as a prominent model to elucidate the functions and regulation of monocytes and macrophages. This includes exploring aspects such as phagocytosis, antigen presentation, and cytokine production. Notably, a 2023 study utilized U937 cells to examine the impact of Glycomacropeptide on the inflammatory response in human macrophage cells. This research underscored the anti-inflammatory properties of glycomacropeptide, demonstrating a reduction in cytokine levels within these cell [2].
- Cancer Research: In the realm of oncology, U937 cells are instrumental in dissecting cellular mechanisms and signaling pathways that underlie cancer. They are also pivotal in anticancer drug screening and the evaluation of novel cancer therapies. Reflecting this application, a study implemented the U937 myeloid leukemia cell line to assess the anticancer effects of both fresh and steamed kale juice. Findings from this study indicated that the juice promotes pro-apoptotic activities in cancer cells via a caspase-dependent pathway [3].
- Toxicology Studies: U937 cells are also employed to investigate the cytotoxic effects of environmental pollutants and various chemicals. For instance, one study used the U937 cell line, among others, to evaluate the potential cytotoxic effects of polyethylene microplastics [4]. This study, along with others, highlights the importance of U937 cells in toxicology, providing a model for understanding how substances interact with human monocytic cells and their potential impact on human health.
Incorporating confocal laser scanning microscopy, researchers can visualize and quantify the phagocytic activity of U937 cells, aiding in the phenotyping of their responses to various stimuli, including infectious agents. Cell line ontologies and accurate karyotype information further enhance the precision of such studies.
U937 cells: Research publications
The following are some interesting and prominent research studies featuring U937 cells.
Magnoflorine enhances LPS-activated pro-inflammatory responses via MyD88-dependent pathways in U937 macrophagesThis study published in Planta Medica (2018) proposed that a major bioactive metabolite obtained from the Tinospora crispa plant has a high potential on augmenting immune responses in U937 macrophages.
Effect of Peganum harmala seeds extract on nitric oxide in U937 monocytes and macrophagesThis research paper was published in the International Journal of Medical Laboratory in 2020. In this study, researchers evaluated the potential effects of Peganum harmala seed extract on nitric oxide production in U937 monocytes and macrophages.
Evaluation of potential toxicity of polyethylene microplastics on human derived cell linesThis study published in Science of the Total Environment (2022) assessed the potential cytotoxic effect of environmental pollutants, i.e., polyethylene microplastics, on U937, THP-1, and other three human cell lines.
Effects of Vitex trifolia L. leaf extracts and phytoconstituents on cytokine production in human U937 macrophagesThis research was published in 2020 in BMC Complementary Medicine and Therapies journal. The study explored the effects of different extracts prepared from Vitex trifolia L. plant leaves on the production of cytokines in U937 macrophages.
Low-dose ionizing radiation exposure represses the cell cycle and protein synthesis pathways in in vitro human primary keratinocytes and U937 cell linesThis article published in PLOS One journal (2018) explored the potential effects of low-dose ionizing radiations in U937 cell line and primary keratinocytes.
Resources for U937 cell line: Protocols, Videos, and More
U937 cells are extensively used research tools. Some valuable resources explaining the cell culturing and differentiation protocol of U937 cells are mentioned here:
- U937 differentiation protocol: This document contains a protocol for differentiating U937 cells. Moreover, it also has a protocol for culturing U937 human myeloid leukemia cells
- Subculture of suspension cells: This is a video showing the general protocol for subculturing suspension cell lines like U937.
- U937 cell line: This website contains a lot of information on U937 cells. It describes subculturing, freezing, and thawing protocols for U937 monocytes and macrophages.
U937 Cell Line Research Applications FAQ
The U937 cell line is a human myeloid cell line derived from a patient with histiocytic lymphoma. It is used extensively as a model for studying the biology of monocytes/macrophages, including their phagocytic activity, responses to infectious agents, and their role in the immune system.
U937 cells are used as macrophage models to study the production and regulation of cytokines, substances that are critical in cell signaling in the immune system. Their study can provide insights into the neurobiology of cytokines, including the roles these signaling molecules play in inflammation and neuroimmune interactions.
Yes, U937 cells are valuable in cytogenetic characterization due to their well-documented genomic features. This includes the study of centromeres, homologous chromosomes, and genome instability, which are important for understanding the genetic basis of diseases.
U937 cells are frequently employed to investigate the molecular pathways of apoptosis due to their ability to undergo programmed cell death in response to various stimuli. This makes them a powerful tool for understanding the cellular mechanisms underlying cancer and other diseases.
Research using U937 cells has been pivotal in examining genome reorganization and the role of specific genes, such as those located on chromosome 11 and parts of chromosomes 16, in cancer development and progression.
Centromere capture in U937 cells can reveal details about chromosome rearrangements and their implications for cell division and stability, providing insights into chromosomal abnormalities that often occur in cancer cells.
Absolutely. The U937 cell line, due to its monocyte-like characteristics, including the expression of cell surface receptor complexes such as the human DC-SIGN protein, is frequently used to study the immune response to infections, including the dengue virus.
U937 cells share many features with primary monocytes, making them a good substitute for studies that cannot use primary cells. When compared to THP-1 cells, another myeloid line, U937 cells may differ in aspects such as differentiation potential and response to stimuli, which is significant when choosing a model for specific experimental needs [5].
U937 cells are used to screen and test the efficacy of antibiotics and anticancer drugs, especially due to their relevance in modeling the human immune response and their known apoptotic pathways, which can be targeted in cancer therapy.
Accurate karyotype information for U937 cells is available upon request from various cell line catalogues and repositories that maintain comprehensive records, including information on any known chromosome 20 rearrangements or other genetic anomalies.
References
- Chanput, W., V. Peters, and H. Wichers, THP-1 and U937 Cells. The Impact of Food Bioactives on Health: in vitro and ex vivo models, 2015: p. 147-159.
- Córdova-Dávalos, L.E., et al., Protective Effect of Glycomacropeptide on the Inflammatory Response of U937 Macrophages. Foods, 2023. 12(7): p. 1528.
- Pungpuag, S., S. Boonpangrak, and Y. Suwanwong, Anti-Leukemic Effects on a U937 Cell Line of Fresh and Steamed Chinese Kale Juice and Their Pro-Apoptotic Effects via a Caspase-Dependent Pathway. Foods, 2023. 12(7): p. 1471.
- Gautam, R., et al., Evaluation of potential toxicity of polyethylene microplastics on human derived cell lines. Science of the Total Environment, 2022. 838: p. 156089.
- Chanput, W., J.J. Mes, and H.J. Wichers, THP-1 cell line: an in vitro cell model for immune modulation approach. International immunopharmacology, 2014. 23(1): p. 37-45.