Microfabricated apparatus for cell based assays

Abstract

Apparatus and methods are provided for performing cell growth and cell based assays in a liquid medium. The apparatus comprises a base plate supporting a plurality of micro-channel elements, each micro-channel element comprising a cell growth chamber, an inlet channel and an outlet channel, a cover plate positioned over the base plate to define the chambers and connecting channels. Means are incorporated in the cell growth chambers, for cell attachment and cell growth. In particular, the invention provides a rotatable disc microfabricated for performing cell growth and cell based assays. The apparatus and method can be used for the growth of cells and the detection and measurement of variety of biochemical processes and products using non-invasive techniques, that is techniques which do not compromise the integrity or viability of cells.

1 .- 19 . (canceled) 
     
     
         20 . A method for determining the effect of a test substance on cell migration, which method comprises:
 a) providing an apparatus having
 i) a base plate supporting a plurality of micro-channel elements, each comprising a cell growth chamber, an inlet channel for supplying liquid sample thereto and an outlet channel for removal of liquid sample therefrom; 
 ii) a cover plate positioned over said base plate, said cover plate extending over said elements so as to define said chambers and channels; and 
 iii) barrier means in said cell growth chambers for impeding the passage of cells in the cell growth chamber; 
   b) introducing said cells into said apparatus and causing said cells to be transported to one side of the barrier means in one or more cell growth chambers in said apparatus,   c) providing one or more samples of test substances whose effect on cell migration is to be measured under conditions so as to cause said cells to be exposed to said substances, and   d) determining migration of cells through said barrier in response to said substance or substances.   
     
     
         21 . The method according to  claim 20 , wherein said cell migration is chemotaxis. 
     
     
         22 . The method according to  claim 21 , wherein a chemoattractant is placed on the other side of said barrier means. 
     
     
         23 . The method according to  claim 20 , wherein said barrier means comprise raised moulded structures disposed on the base portion of the cell growth chamber to form pillars. 
     
     
         24 . The method according to  claim 23 , wherein gaps between the pillars are between 5 and 50 μm. 
     
     
         25 . The method according to  claim 20 , wherein at least some of the micro-channel elements each comprise one or more assay chambers connected in line between said cell growth chamber and said outlet channel. 
     
     
         26 . The method according to  claim 20 , wherein the apparatus comprises a flow system for causing liquid flow through the micro-channel elements. 
     
     
         27 . The method according to  claim 26 , wherein the liquid flow is controlled by centrifugal force. 
     
     
         28 . The according to  claim 20 , wherein the base plate comprises a rotatable disc which is microfabricated to provide a sample introduction port located towards the center of the disc and connected to an annular sample reservoir, and wherein the micro-channel elements are radially dispersed on the disc with their respective input channels connected to receive sample from the reservoir. 
     
     
         29 . The method according to  claim 20 , wherein the growth chambers comprise localised regions modified to have surface properties which promote cell growth. 
     
     
         30 . The method according to  claim 20 , wherein weakly attached cells in the growth chambers are removed by centrifugal force.