Cell spraying device, method and sprayed cell suspension
The invention provides a device and methods suitable for producing a cellular spray of cells. The sprayed cells are of interest for covering and growing on a surface, including a skin wound. In applying the method and/or using the device, cells for grafting onto a patient are dispersed in a solution and sprayed with the device for distribution over the recipient's graft site.
1. A method to treat a wounded area of skin on a human subject, comprising:
providing a single cell-suspension of cells comprising progenitor skin cells in a serum-free physiological solution in a sterilizable container, wherein the cells are obtained from the subject's normal skin tissue that has been treated with enzymes so as to release the cells from the dermal-epithelial cell junction, wherein the skin cells have not been subjected to ex vivo or in vitro expansion;
contacting the single-cell suspension of cells with a gas flow at an outlet of the container to create droplets of the suspension at a flow-controlled spray head; and
spraying the droplets onto the wounded area of skin without forming a closed cell sheet so that the single cells are distributed directly and evenly and the cells regenerate normal skin by in situ multiplication to heal the wounded area in the absence of applying a preformed skin graft.
2. The method of claim 1 wherein the suspension comprises uncultured cell types in a ratio comparable to that found in normal skin.
3. The method of claim 1 or 2 wherein the cells comprise basal keratinocytes, Langerhans cells, fibroblasts and melanocytes.
4. The method of claim 1 wherein the cells in the suspension have a morphology that is similar to the cells in the droplets.
5. The method of claim 2 wherein the suspension comprises skin progenitor cells.
6. The method of claim 1 , wherein the suspension is filtered to remove large cellular congregates.
7. The method of claim 6 , wherein the filter has a cut-off of 5-100 cell congregates.
8. The method of claim 1 wherein the enzymes comprise dispase and trypsin.
9. The method of claim 1 wherein the enzymes comprise collagenase.
10. The method of claim 1 wherein the container is a syringe and the suspension is delivered to the outlet of the spray head by continuous force application to the container.
11. The method of claim 1 wherein the wounded area is burned.