Seeds: R & D of cell-based gene therapy with making use of adipocytes
We have been developing "transduced adipocyte-based medicine" using human
adipocytes as a device for sustained release of therapeutic protein(s), and
have successfully established the manufacturing process (GMP).
We are continuing to expand our versatile technology to various intractable diseases, developing transduced adipocyte-based medicine to contribute to the benefit of patients suffered from various intractable diseases.
Gene therapy of intractable diseases by transduced adipocytes secreting therapeutic protein
Advantage of adipocytes as recipient cells for gene-transduction
The recipient cells are required not only to express the transgene stably but also to be obtained safely and less invasively when excised from patients and to be prepared highly homogeneous in cell population. And the characteristic of the cells must remain stable, not affected by transduction process. The adipocytes obtained have been proven to be excellent as recipient cells for gene transduction.
Superiority of gene therapy by making use of adipocytes
- Transfer the gene to the target cells reliably?
- Supply effective dose of protein for therapy?
- Transfer the gene to the cells efficiently?
- Maintain the transgene stably?
- Avoid transduction of non-target cells?
- Transduction causes any change in the original characteristics of the cells(weakening/transformation)?
- Provide sustained release of therapeutic protein (expected outcome of gene therapy)?
Gene therapy technology using adipocytes
- Highly purified adipocytes are easily isolated and cultured, and are reliably transduced by therapeutic gene. The expression level of the therapeutic protein can be determined in advance.
- High transduction rate can be achieved.
- Transgene can be maintained stably.
- Adipocytes have a low risk of transformation reportedly, and tumorigenesis of the transduced adipocytes was not observed. No cellular damage of the transduced adipocytes was detected.
- Adipocytes are adherent cells with less possibility to disseminate to other organs.
- Adipocytes have a long life span, allowing the long sustained supply of the therapeutic protein.
Efficacy Study Result
1. Implantation of insulin gene transduced adipocytes to diabetic mice and excision of the implant.
Insulin gene transduced adipocytes was implanted into diabetic mice, and long term improvement of blood glucose level was observed. This effect was lost by excision of the implant.
Blood glucose control by human insulin gene transduced mouse adipocytes
Transition of blood glucose level in STZ diabetic model mice and disappearance of the effect by excision of the implant
2. Excretion of LCAT into blood after implantation of LCAT gene transduced adipocytes to normal mice
LCAT gene transduced adipocytes were implanted to normal mice, and sustained secretion of LCAT in the blood was observed.
Sustained supply of therapeutic protein by "hLCAT gene transduced adipocytes"
Scenario toward practical application
Cellgentech, Inc. will conduct the step-wise development of "transduced adipocyte-based medicine" as the gene therapy making use of adipocytes, from the following point of view.
Scenario of realization ~ Pipeline: From rare diseases to lifestyle-related diseases~
From congenital metabolic diseases to lifestyle-related diseases
Starting from the applicable diseases according to the cell therapy guideline, we will apply our technology to lifestyle-related diseases, arteriosclerotic disease, cancer, and neurodegenerative diseases.
(Reference) Guideline for Gene Therapy (Summary)
Applicable to diseases indicated for gene therapy/ rare diseases (specific
intractable diseases) and chronic diseases carrying a risk of life crisis and
Outline of Guideline for Clinical Studies on Gene Therapy (March 27, 2002)
Gene Therapy implies the administration to the human body genes or congenic cells for the purpose of treating disease.
- Serious hereditary diseases, cancer, acquired immunodeficiency syndrome, other life-threatening diseases and diseases seriously impairing bodily function.
- Diseases for which it is most reasonable to assume that the effectiveness of treatment based on the clinical studies of gene therapy will be superior to any alternative treatments currently available.
- Diseases for which it is most reasonable to assume that the advantages accruing to the study subject from this study will outweigh all disadvantages.