Cellular therapy

Cellular therapies in transplantation and cancer are based on specific cells separated or sorted from human blood, bone marrow, or cord blood by means of their specific cell surface markers or cell differentiation antigens, e.g., CD3, CD4, CD8, CD 14, CD 19, and CD34. For example, the CD34+ stem cells, especially those derived from human embryos, have the capacity to differentiate in culture to generate different somatic cells, e.g., liver cells, heart cells, neurons, etc. This exploding field of research is now termed regenerative medicine. 

Other. Autologous, allogenic, and xenogenic cells which do not specifically fit above. This group includes cellular therapies such as extracorporeal liver assist... 

Specific (local tissue tolerance) toxicity studies may be necessary due to special characteristics of the product or the clinical indication. Adjuvanted vaccines are routinely evaluated for local (injection site) reactions, and cellular therapies are routinely screened for tumorigenic potential. Research is also needed to better predict the sensitizing potential of biological products and to determine the relevance of serum antibody levels following repeat dosing in animals and humans. 

Cellular therapy employing Foxp3-expressing regulatory T cells (Tregs) holds the promise to replace and/or supplement indiscriminatory... 

The TGAhas also initiated development of two new regulatory frameworks for in nff ro diagnostic devices (IVDs) and human tissues and cellular therapies, which will include ex vivo reagents, to be harmonised with international best practice. It is expected that implementation will occur from early2006 for IVDs and mid-2006 for human tissues and cellular therapies. 

Transplantation of dopaminergic tissue (fetal substantia nigra tissue) has been reported to confer benefit in some parkinsonism patients, but the results are conflicting. In one controlled trial, symptomatic benefit occurred in younger (less than 60 years old) but not older patients. In another trial, benefits were inconsequential. Furthermore, uncontrollable dyskinesias occurred in some patients in both studies. This was attributed to a relative excess of dopamine from continued fiber outgrowth from the transplant. Further basic studies are required before other trials of cellular therapies are undertaken, and such approaches therefore remain investigational. 

General Safety According the Food and Drug Administration (FDA), cellular therapy products are exempt from general safety testing [21 CFR 610.11(g)(1)]. 

Dominici, M., Le Blanc, K., Mueler, I., et al. (2006), Minimal criteria for defining multi-potent mesenchymal stromal cells. The International Society for Cellular Therapy position statement, Cytotherapy, 8(4), 315-317. 

Adult Neural Stem Cells and Cellular Therapy... 

Adult Neural Stem Cells A Model of Choice for Cellular Therapy for CNS Diseases and Injuries... 

Cell types of various sources and merits, such as cells derived from embryos - embryonic stem cells - from fetuses, or from tissues and organs, have been considered for cellular therapy in the CNS. Because they do not carry ethical and political concerns, and allow rewiring of the CNS, adult NSCs offer of model of choice for cellular therapy. Aside from the ethical and political concerns, NSCs offer a powerful tool for cellular therapy, particularly for cellular transplantation. 

The recent confirmation that neurogenesis occurs in the adult brain, and isolation and characterization in vitro of neural progenitor and stem cells from the adult CNS, open new opportunities for cellular therapy in the CNS. Adult-derived neural progenitor and stem cells circumvent the ethical and political concerns associated with their embryonic and fetal counterparts, and offer the opportunity to treat a broad range of CNS diseases and injuries, making adult NSCs a model of choice for cellular therapy in the CNS. 

Reprinted from Taupin P. Adult neural stem cells and cellular therapy. Journal of Stem Cells (2006) 1(1) 47-55, with permission from Nova Science Publishers, Inc. 

Cellular therapy is the replacement of lost or dysfunctional tissues with new ones. Various cell types have been evaluated and considered for therapy. In the CNS, fetal neuronal tissue has been particularly evaluated for its merit in treating neurological diseases and injuries [1]. While numerous experimental and clinical transplantation studies showed that fetal neuronal transplants improve functional deficits in models of CNS diseases [2-5], others reported less positive outcomes [6, 7]. In addition, the rate of survival of fetal neuronal cells transplanted into the adult brain is relatively low, requiring large quantities of tissue, generally from several fetuses, for therapy. Researchers are looking at other opportunities for cellular therapy, particularly in the CNS. 

Taupin, P. (2006). Adult neural stem cells, neurogenic niches and cellular therapy. Stem Cell Reviews, 2, 213-9. 

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