Human blood-derived materials are essential tools in biomedical research, enabling scientists to study immune responses, disease mechanisms, and therapeutic strategies. Human blood in various forms allows scientists to discover and diagnose countless diseases, as well as treat them more effectively.
Within every drop of human blood, laboratory technicians can find peripheral blood mononuclear cells, or PBMCs for short. Over the last few decades, these biospecimens have been used a lot more in research than any others because PBMCs play a central role in immune surveillance and immune response regulation as researchers develop personalized therapies; demand for PBMCs for sale increases. Good assets let them test various lab discoveries on real-life cells, proving their potential success.
Peripheral blood mononuclear cells are like mirrors into the human immune system. Today, we will learn more about PBMCs, where they are derived from, and how the right isolation method can prevent their contamination.
What Is PBMC?
Peripheral blood mononuclear cells (PBMCs) are a heterogeneous population of blood cells containing a single round nucleus, primarily consisting of lymphocytes and monocytes. They are less dense than other cells and are typically isolated from the peripheral circulation, along with cells like RBCs and granulocytes. Yet, they can be derived from different source materials, such as buffy coat and bone marrow. The composition of PBMC will then depend on the material. Typical components of PBMC, regardless of the source, are:
- lymphocytes (70–90%);
- monocytes (10–30%);
- trace dendritic cells.
As a huge part of the immune system, they give scientists a glimpse into the host’s defense system of the organism. That’s why these assets became an essential resource in immunological research.
PBMCs in Clinical Research
The last several decades saw an increase in the PBMCs use in clinical research. Thousands of studies involve these cells to find effective treatment for cancer, autoimmune disease, arthritis, lupus, multiple sclerosis, and other conditions.
PBMC-derived T cells can be used as starting material for cell therapy development, including CAR-T approaches. When testing a new drug, they can also show how a human’s immune system will respond to the components. This can prevent drug ineffectiveness and adverse effects.
But not all PBMCs can be used in the laboratory. The samples should be high-quality and pure to be suitable for professional research. Although not everyone can derive samples or perform isolation in-house, it’s possible to purchase suitable, contamination-free cells from reliable providers like Preci.
Main PBMC Sources In The Human Organism
Laboratories that can derive their own PBMCs can do so in several ways. The most common source material in the human body is peripheral blood, or whole blood. These samples usually contain an anticoagulant such as K2EDTA or LiHep. Depending on the patient’s age, the number of cells per milliliter of blood can vary. The usual concentration in whole blood is 0.5–3×106 cells/mL.
Buffy coat is also quite common, since it’s a byproduct of blood donation and can be easily isolated from whole blood. The buffy coat also contains a higher count of PBMCs than whole blood. A typical 50mL buffy coat sample can contain up to 500 million PBMCs.
Many researchers prefer to work with leukoreduction system chambers. These are commonly removed from donor blood when processed and are often donated to laboratories for research. The concentration of PBMCs can reach up to 1 billion, despite the low volume. Leukopaks typically provide a high-volume source of PBMCs with substantially higher cell yields than standard blood collections.
PBMC Isolation — Most Important Step in Clinical Research
Without proper isolation, any PBMC will lose its effectiveness. That’s why most pre-made samples come already isolated and ready to use. However, the process can also be done in-lab.
Density-Based Isolation Methods
The most popular approach was developed in the 1960s: the Ficoll Overlay technique, or density gradient medium (DGM) centrifugation. The Ficoll density gradient method remains one of the most widely used approaches, although it is labor-intensive and requires careful handling.
A frit barrier can be used during the centrifugation step. It’s faster and yields better results when separating blood layers. The most common systems with a frit barrier are Accuspin, SepMate, and LeucoStep. Despite its benefits, it might lower the PBMC count.
Sometimes, the process of PBMC isolation is carried out on-site after the donation. Cells are partially processed by using the usual centrifugation method in cell preparation tubes (CPT). Inside a CPT, you will find an anticoagulant and a gel product that aids blood layer separation. Although it can save time in the laboratory, low-quality blood samples might completely prevent the isolation process.
Immunomagnetic Cell Separation
One of the most effective isolation techniques is immunomagnetic cell separation. Immunomagnetic separation enables targeted enrichment of specific immune cell populations with high purity and recovery. Laboratory researchers can use the same column-based or column-free approach to enrich a sample. The platforms allow for fast, effective isolation, but they are a lot more expensive and not as easy to utilize with bigger samples.
Quality Assessment and Storage
After isolation, every laboratory has to check the PBMC quality in the samples. Technicians can count cells and assess their viability manually by staining dead cells with trypan blue exclusion. High-quality cryopreserved PBMC preparations commonly demonstrate viability above 90% after thawing, depending on processing and application requirements.
Many laboratories deem manual counting too time-consuming. The result also depends on the technician due to the human factor. Nowadays, automation is more common. Automated counters are faster and have a standardized approach to cell counting in all clinical research processes. Now, PBMCs are ready to be used. If not used immediately, all assets can be stored long-term. Controlled-rate PBMC freezing is the best option for cell storage in laboratory settings.
PBMCs as a Mirror of Real-Life Immune Activity
PBMCs have a unique composition and can effectively demonstrate how the human immune system will react to diverse treatments. Since they are a mirror of real-life immune activity, these cells have been used in biological research for decades.
Nowadays, PBMCs are derived from different sources and isolated via various methods. The resulting asset is used to develop effective therapies for conditions like cancer, sclerosis, and lupus.
Final Note
PBMCs provide researchers with a practical window into human immune activity, but they should not be treated as a complete representation of every immune response occurring inside the body. Immune cells found in tissues, lymph nodes, bone marrow and tumour environments may behave differently from cells circulating in peripheral blood.
The reliability of PBMC-based research depends on more than cell viability alone. Donor characteristics, anticoagulant choice, transportation conditions, processing delays, isolation technique, freezing rate, storage temperature, thawing procedure and downstream assay design can all influence cell recovery, phenotype and function. Laboratories should therefore use validated procedures, record important pre-analytical variables and apply consistent quality-control criteria across every sample group.
When appropriately collected, processed and characterized, PBMCs remain one of the most valuable human biospecimens for immunology, drug development, biomarker research, vaccine studies, single-cell analysis and cell-therapy development.
Research and Medical Disclaimer
This article is provided for general educational and scientific information only. It is not medical advice, diagnostic guidance, treatment advice or a substitute for an approved laboratory protocol.
The isolation, storage, transportation and experimental use of human blood-derived materials must be performed by appropriately trained personnel under applicable institutional biosafety procedures, ethical approvals, informed-consent requirements, donor-privacy protections and local regulations. Researchers should follow their institution’s standard operating procedures and validate all collection, processing, cryopreservation and assay methods for their intended application.
Cell yields, purity, viability and functional performance can vary considerably according to donor characteristics, source material, collection conditions, isolation method and storage history. Any viability percentages or expected cell yields mentioned in this article should therefore be treated as general examples rather than guaranteed specifications.
The mention of any supplier, laboratory product, separation platform or commercial service does not constitute an endorsement. Researchers should independently assess documentation relating to donor consent, infectious-disease testing, sample traceability, quality control, regulatory status and fitness for the intended research use.
References
- Riedhammer C, Halbritter D, Weissert R. Peripheral blood mononuclear cells: isolation, freezing, thawing, and culture. Methods in Molecular Biology. 2016;1304:53–61. DOI: 10.1007/7651_2014_99.
- Dinh B, Hoeksema MA, Spann NJ, Rendler J, Cobo I, Glass CK, Yeang C. Isolation and cryopreservation of highly viable human peripheral blood mononuclear cells from whole blood: a guide for beginners. Journal of Visualized Experiments. 2024;(212):e66794. DOI: 10.3791/66794.
- Fuss IJ, Kanof ME, Smith PD, Zola H. Isolation of whole mononuclear cells from peripheral blood and cord blood. Current Protocols in Immunology. 2009;85:7.1.1–7.1.8. DOI: 10.1002/0471142735.im0701s85.
- Posevitz-Fejfár A, Posevitz V, Gross CC, Bhatia U, Kurth F, Schütte V, Bar-Or A, Meuth SG, Wiendl H. Effects of blood transportation on human peripheral mononuclear cell yield, phenotype and function: implications for immune cell biobanking. PLoS ONE. 2014;9(12):e115920. DOI: 10.1371/journal.pone.0115920.
- Germann A, Oh YJ, Schmidt T, Schön U, Zimmermann H, von Briesen H. Temperature fluctuations during deep-temperature cryopreservation reduce PBMC recovery, viability and T-cell function. Cryobiology. 2013;67(2):193–200. DOI: 10.1016/j.cryobiol.2013.06.012.
- Kleeberger CA, Lyles RH, Margolick JB, Rinaldo CR, Phair JP, Giorgi JV. Viability and recovery of peripheral blood mononuclear cells cryopreserved for up to 12 years in a multicenter study. Clinical and Diagnostic Laboratory Immunology. 1999;6(1):14–19. DOI: 10.1128/CDLI.6.1.14-19.1999.
- Knörck A, Marx S, Friedmann KS, Zophel S, Lieblang L, Hassig C, et al. Quantity, quality, and functionality of peripheral blood cells derived from residual blood of different apheresis kits. Transfusion. 2018;58(6):1516–1526. DOI: 10.1111/trf.14616.
- Maecker HT, McCoy JP, Nussenblatt R. Standardizing immunophenotyping for the Human Immunology Project. Nature Reviews Immunology. 2012;12(3):191–200. DOI: 10.1038/nri3158.
- Hanamsagar R, Reizis T, Chamberlain M, Marcus R, Nestle FO, de Rinaldis E, Savova V. An optimized workflow for single-cell transcriptomics and repertoire profiling of purified lymphocytes from clinical samples. Scientific Reports. 2020;10(1):2219. DOI: 10.1038/s41598-020-58939-y.
- Levine BL, Miskin J, Wonnacott K, Keir C. Global manufacturing of CAR T-cell therapy. Molecular Therapy: Methods & Clinical Development. 2017;4:92–101. DOI: 10.1016/j.omtm.2016.12.006.