Treatment of Alopecia By Micropore Delivery of Stem Cells

Abstract

A method of restoring hair to skin that has suffered hair loss includes optically ablating an array of spaced-apart microchannels or voids into the skin and transplanting into the voids stem cells, a scaffold and a differentiation factor for causing the stem cells to differentiate into hair follicles.

1 . A method of treating or preventing hair loss in a subject in need thereof, the method comprising:
 irradiating skin with pulses of laser irradiation at a rate of 10 per second to 5000 per second and at a pulse energy of up to 150 mJ per pulse to form a plurality of micropore channels, wherein the micropore channels extend into dermis of the skin; and   implanting a composition into the micropore channel,   wherein the composition comprises stem cells and a growth media, the laser irradiation has an absorption coefficient in water of about 100 cm −1  to 12,300 cm −1 , the micropore channels have a depth of about 200 μm to 4 mm and a density of less than 2500 voids per cm 2  per pass, and viable tissue separating adjacent micropore channels has a width, at a narrowest point thereof, between about 50 μm and 500 μm.   
     
     
         2 . The method of  claim 1 , wherein the composition is implanted 1 min after the formation of the plurality of micropore channels. 
     
     
         3 . The method of  claim 2 , wherein the composition is implanted 1 hr after the formation of the plurality of micropore channels. 
     
     
         4 . The method of  claim 3 , wherein the composition is implanted 1 day after the formation of the plurality of micropore channels. 
     
     
         5 . The method of  claim 1 , wherein the plurality of micropore channels are elongated. 
     
     
         6 . The method of  claim 5 , wherein the viable tissue separates the plurality of elongated micropore channels. 
     
     
         7 . The method of  claim 1 , wherein the composition further comprises a scaffold. 
     
     
         8 . The method of  claim 7 , wherein the scaffold is selected from the group consisting of poly(lactic-co-glycolic acid) (PLGA), fibronectin, collagen 1, and collagen 3. 
     
     
         9 . The method of  claim 8 , wherein the scaffold is PLGA. 
     
     
         10 . The method of  claim 1 , wherein the stem cell is an embryonic stem cell, fetal stem cell, umbilical cord blood stem cell or an adult stem cell 
     
     
         11 . The method of  claim 10 , wherein the stem cell is an adult stem cell. 
     
     
         12 . The method of  claim 11 , wherein the adult stem cell is derived from adipose tissue, hair follicle, or bone marrow. 
     
     
         13 . The method of  claim 12 , wherein the stem cell is hair follicle cell. 
     
     
         14 . The method of  claim 10 , wherein the composition further comprises a melanocyte stem cell. 
     
     
         15 . The method of  claim 1 , wherein the growth media comprises a proliferation-inducing growth factor. 
     
     
         16 . The method of  claim 15 , wherein the growth factor is selected from the group consisting of epidermal growth factor (EGF), amphiregulin, acidic fibroblast growth factor (aFGF or FGF-1), basic fibroblast growth factor (bFGF or FGF-2), and transforming growth factor alpha (TGFα), or combinations thereof. 
     
     
         17 . The method of  claim 1 , further comprising:
 administering a hair-follicle differentiation factor.   
     
     
         18 . The method of  claim 17 , wherein the differentiation factor is selected from the group consisting of FGF2, FGF4, noggin, PDGF, and PTHrp, or combinations thereof.