Compositions and methods of cell attachment

Abstract

Compositions, devices and methods are described for improving adhesion, attachment, and/or differentiation of cells in a microfluidic device or chip. In one embodiment, one or more ECM proteins are covalently coupled to the surface of a microchannel of a microfluidic device. The microfluidic devices can be stored or used immediately for culture and/or support of living cells such as mammalian cells, and/or for simulating a function of a tissue, e.g., a liver tissue, muscle tissue, etc. Extended adhesion and viability with sustained function over time is observed.

We claim: 
     
         1 - 23 . (canceled) 
     
     
         24 . A method of culturing cells, comprising: a) providing a microfluidic device comprising a microchannel comprising a surface, said surface reacted with an ultraviolet light reactive portion of a bifunctional crosslinker using an ultraviolet light source, said microchannel in fluidic communication with a fluid source comprising a fluid; b) covalently attaching one or more extracellular matrix proteins to a chemically-reactive portion of said bifunctional crosslinker so as to create a treated surface; c) seeding viable epithelial cells on said treated surface so as to create attached epithelial cells; d) flowing said fluid from said fluid source through said microchannel so as to create flowing conditions; and e) culturing said attached epithelial cells under said flow conditions such that said attached epithelial cells remain attached and viable for at least 7 days. 
     
     
         25 . The method of  claim 24 , wherein the light reactive portion is selected from the group consisting of nitrophenyl, diazirine, and azides. 
     
     
         26 . The method of  claim 24 , wherein said light reactive portion is a nitrophenyl azide. 
     
     
         27 . The method of  claim 24 , wherein said one or more extracellular matrix proteins comprises collagen. 
     
     
         28 . The method of  claim 24 , wherein said one or more extracellular proteins comprises RGD or a RGD motif. 
     
     
         29 . A method of culturing cells, comprising: a) providing a microfluidic device comprising a microchannel comprising a surface, said surface reacted with a photoactivatable nitrophenyl azide portion of a bifunctional crosslinker using an ultraviolet light source, said microchannel in fluidic communication with a fluid source comprising a fluid; b) covalently attaching one or more extracellular matrix proteins to a chemically-reactive portion of said bifunctional crosslinker so as to create a treated surface; c) seeding viable epithelial cells on said treated surface so as to create attached epithelial cells; d) flowing said fluid from said fluid source through said microchannel so as to create flowing conditions; and e) culturing said attached epithelial cells under said flow conditions such that said attached epithelial cells remain attached and viable for at least 7 days. 
     
     
         30 . The method of  claim 29 , wherein said one or more extracellular matrix proteins comprises collagen. 
     
     
         31 . The method of  claim 29 , wherein said one or more extracellular proteins comprises RGD or a RGD motif. 
     
     
         32 . A method of treating a microfluidic device, comprising: a) providing: i) a microfluidic device comprising a microchannel comprising a surface; ii) a fluidic source comprising a fluid, wherein said fluidic source is in fluidic communication with said microchannel; iii) a source of ultraviolet light and iv) a bifunctional crosslinker having an ultraviolet light reactive portion and a chemically reactive portion; b) exposing said ultraviolet light reactive portion of said heterobifunctional crosslinker to said source of ultraviolet light thereby covalently attaching said crosslinker to said surface; c) covalently attaching one or more extracellular matrix proteins with said chemically reactive portion of said crosslinker so as to create a treated surface; d) seeding viable epithelial cells on said treated surface so as to create attached epithelial cells; e) flowing said fluid from said fluid source through said microchannel so as to create flow conditions; and f) culturing said attached epithelial cells under said flow conditions such that said attached epithelial cells remain attached and viable for at least 7 days. 
     
     
         33 . The method of  claim 32 , wherein the light reactive portion is selected from the group consisting of nitrophenyl, diazirine, and azides. 
     
     
         34 . The method of  claim 32 , wherein said light reactive portion is a nitrophenyl azide. 
     
     
         35 . The method of  claim 32 , wherein said one or more extracellular matrix proteins comprises collagen. 
     
     
         36 . The method of  claim 32 , wherein said one or more extracellular proteins comprises RGD or a RGD motif.