Cell suspension preparation technique and device
The present invention provides for methods and devices suitable for producing a transplantable cellular suspension of living tissue suitable for grafting to a patient. In applying the method and/or in using the device, donor tissue is harvested, subjected to a cell dissociation treatment, cells suitable for grafting back to a patient are collected and dispersed in a solution that is suitable for immediate dispersion over the recipient graft site.
1. An apparatus for developing peri-operatively to a patient a cell suspension from a skin tissue sample, and for immediately applying the cell suspension to a graft site of the patient, comprising:
a first member, a second member, a base portion, an enzyme solution comprising an amount of enzyme sufficient to dissociate cellular stratum in a skin tissue sample, and a nutrient solution suitable for direct application to the graft site, wherein the nutrient solution is free of xenogenic serum and used to suspend cells harvested following release from the skin tissue sample; wherein:
(i) the first member comprises:
(a) a storage compartment configured to store a set of tools for cell harvesting and a dispersing device configured to apply the cell suspension to the graft site;
(b) an aperture extending longitudinally through the first member configured to allow a neck of a vial to protrude through the first member and arranged above a heating unit configured to heat the vial containing the enzyme solution to a predetermined temperature and maintain the predetermined temperature, wherein the enzyme solution, after being heated, is used to incubate the skin tissue sample to dissociate the cellular stratum therein, without encouraging in vitro cellular multiplication; and
(c) a filter recess comprising a filter means of a filter size between 50 μm and 200 μm, configured to remove cellular congregates greater than the filter size from cells harvested from the skin tissue sample, to form the cell suspension that is suitable for immediate dispersion to the graft site;
(ii) the first member is located within the base portion, and the base portion comprises:
(a) the heating unit; and
(b) a containment field sized to fit the vial to be heated by the heating unit; and
(iii) the second member is seated within the first member and the second member comprises:
a top surface, an underside, and sidewalls, such that when inverted, the sidewalls extend upward and comprise a reservoir area configured to withhold the skin tissue sample and at least a portion of the nutrient solution in fluid containment, wherein the reservoir area is of sufficient size to permit manipulation of the skin tissue sample, permitting separation of the cellular stratum and harvesting of cells from the cellular stratum suitable for grafting, without encouraging in vitro cellular multiplication.
2. The apparatus of claim 1 , wherein the aperture further houses the vial protruding therethrough and into which the skin tissue sample may be placed for exposure to the enzyme solution.
3. The apparatus of claim 1 , wherein the heating unit is controlled by circuitry permitting activation of the heater when required.
4. The apparatus of claim 1 , wherein the heating unit is operably linked to a timer mechanism adapted to heat the enzyme solution for a pre-defined period of time.
5. The apparatus of claim 1 , wherein the heating unit is provided with an adjustable temperature control.
6. The apparatus of claim 1 , further comprising a monitoring means that are capable of indicating that the enzyme solution has reached the predetermined temperature, and/or the amount of time that the enzyme has been in the enzyme solution for.
7. The apparatus of claim 1 , further comprising a means to facilitate mixing of the enzyme solution.
8. The apparatus of claim 1 , wherein the filter recess is adapted to receive and hold a tube into which the cell suspension may be filtered.
9. The apparatus of claim 1 , wherein the fluid containment well serves as a receptacle for a container that holds the nutrient solution.
10. The apparatus of claim 1 , wherein the set of tools include a vessel of the enzyme, a sterile solution for suspension of the enzyme, scalpel, forceps, syringe, medicine dropper, cell filter, and/or wound dressings.
11. The apparatus of claim 1 , wherein the predetermined temperature is between 30 and 37° C.
12. The apparatus of claim 11 , wherein the heating unit maintains the predetermined temperature for at least 45 minutes.
13. The apparatus of claim 1 , wherein the heating unit is a heating pad or heating collar.
14. The apparatus of claim 1 , wherein the nutrient solution is physiological saline.
15. The apparatus of claim 1 , further comprising a closure lid having a locking mechanism adapted to releasably engage the base portion.
16. The apparatus of claim 1 , wherein the storage compartment comprises a seat located around its periphery extending from its inner wall at a depth beneath a surface of the first member that is equivalent to a height of the sidewalls of the second member such that the second member may reside in the storage compartment.
17. The apparatus of claim 1 , wherein the second member further comprises an indent configured to permit lifting of the second member.
18. The apparatus of claim 1 , wherein the dispersing device selected from spray nozzle, pipette, eye-dropper, syringe and/or needle.
19. The apparatus of claim 1 , wherein the first member further comprises a fluid containment well configured to store the nutrient solution.