Cell-based immunotherapy is moving from a largely experimental concept toward a more standardized form of medicine, according to a new review published in Nature Reviews Bioengineering. The field aims to treat cancer, autoimmune disorders and infectious diseases by delivering living immune cells capable of recognizing, attacking or regulating disease. Rather than relying only on a patient’s own cells, researchers are increasingly developing “off-the-shelf” products made from healthy donors or stem-cell sources. These allogeneic therapies could make treatment faster, more consistent and more widely available than approaches that require customized manufacturing for every patient.
The review by Li, Zhu, Shen and colleagues examines two main routes for producing therapeutic immune cells. The first begins with peripheral blood mononuclear cells, a mixed population that includes lymphocytes and monocytes collected from a patient or donor. These cells can be isolated, activated and genetically modified before being returned to the recipient. The second route uses stem cells as a renewable starting material. Haematopoietic stem cells, which naturally generate blood and immune cells, can be expanded or redirected, while pluripotent stem cells can be differentiated into specialized immune populations under controlled laboratory conditions.
This distinction is important because conventional autologous cell therapies are laborious and variable. In an autologous process, a patient’s cells are collected, engineered and expanded before treatment. Disease, age, prior therapies and the condition of the patient’s immune system can all affect the quality and quantity of the starting material. Allogeneic manufacturing instead uses cells from a donor or a banked stem-cell line. A single engineered cell source may therefore be used to produce multiple treatment doses, allowing manufacturing to be performed in advance and under tightly controlled conditions.
Stem-cell engineering has expanded the range of immune cells that can be produced for therapy. T cells remain a central focus because they can identify abnormal cells through antigen-specific receptors and destroy them through cytotoxic mechanisms. Natural killer cells provide another route to immune-mediated killing and can recognize stressed or transformed cells without relying on the same antigen-recognition system as conventional T cells. Macrophages, which engulf material and influence inflammation, are also being developed as therapeutic agents. Each cell type offers distinct biological advantages, but each presents different challenges in generating a stable, potent and clinically useful product.
One of the most prominent technologies discussed in this field is the chimeric antigen receptor, or CAR. A CAR is a synthetic receptor introduced into an immune cell through genetic engineering. Its external binding region is designed to recognize a selected molecular marker, while internal signalling domains activate the cell after target engagement. CAR engineering has been particularly influential in T-cell therapy, but researchers are also adapting the technology for natural killer cells and macrophages. These CAR-equipped cells are intended to improve target recognition, strengthen activation and potentially overcome mechanisms that allow diseased cells to evade natural immunity.
Genetic modification can also be used to improve safety and immune compatibility. Researchers are investigating edits that reduce the ability of donor-derived cells to attack healthy recipient tissues, a complication associated with immune recognition across individuals. Other modifications may limit the capacity of therapeutic cells to trigger excessive inflammation, a process that can produce serious systemic effects. Gene engineering can additionally introduce “safety switches” or other control systems designed to eliminate or deactivate the cells if unwanted toxicity occurs. At the same time, reducing the expression of molecules recognized by the recipient’s immune system may help prolong the survival of transplanted cells.
The review also highlights the importance of differentiation platforms. Producing an immune cell from a stem cell is not simply a matter of adding one factor to a culture. Cells must receive carefully timed combinations of signalling molecules, growth factors and environmental cues that reproduce aspects of blood-cell development. Scientists are refining three-dimensional culture systems, feeder-free methods and scalable bioreactors to control this process. The objective is to generate large numbers of cells with a uniform identity, predictable function and minimal contamination by unwanted or incompletely differentiated cell types.
Manufacturing remains one of the field’s decisive tests. A clinically compatible process must preserve cell viability and activity while meeting strict standards for sterility, genetic stability and product consistency. Cells may need to be frozen, transported and stored without losing their therapeutic properties. Stem-cell-derived products also require extensive characterization to confirm that residual undifferentiated cells do not create safety risks. Advances in automation, closed-system processing and analytical technologies are helping researchers move from small laboratory batches toward reproducible production at a scale suitable for clinical use.
Early clinical evidence is beginning to shape expectations, but the review emphasizes that important questions remain. Researchers must determine how long engineered cells persist in the body, whether they continue functioning after repeated exposure to disease environments and how reliably they reach the tissues where they are needed. Tumours and chronic inflammatory conditions can suppress immune activity, while infectious diseases may impose rapidly changing biological pressures. Future studies will need to compare cell sources, genetic designs and manufacturing strategies directly, while also monitoring delayed toxicities and the long-term consequences of genome editing.
Together, these developments suggest that allogeneic immunotherapy could become a flexible platform rather than a single treatment type. Donor-derived and stem-cell-derived T cells, natural killer cells, macrophages and CAR-engineered variants may eventually be selected according to the disease, target and desired immune response. The review presents this convergence of gene engineering, stem-cell biology and bioprocessing as a foundation for more accessible cellular medicines. Its central message is that therapeutic success will depend not only on making immune cells powerful, but also on making them controllable, compatible, manufacturable and safe enough for broad clinical application.
Subject of Research: Allogeneic immunotherapy using genetically engineered and stem-cell-derived immune cells
Article Title: Allogeneic immunotherapy
Article References: Li, YR., Zhu, Y., Shen, X. et al. Allogeneic immunotherapy. Nat Rev Bioeng (2026). https://doi.org/10.1038/s44222-026-00468-w
Image Credits: AI Generated
DOI: 10.1038/s44222-026-00468-w
Keywords: Allogeneic immunotherapy, cell-based immunotherapy, stem cell engineering, T cells, natural killer cells, macrophages, CAR-engineered cells, gene editing, pluripotent stem cells, therapeutic cell manufacturing
