Abstract: Proto-antigen-presenting surfaces and related kits, methods, and uses are provided. The proto-antigen-presenting surface can comprise a plurality of primary activating molecular ligands comprising a major histocompatibility complex (MHC) molecule configured to bind to a T cell receptor (TCR) of a T cell and a plurality of of co-activating molecular ligands each including a TCR co-activating molecule or an adjunct TCR activating molecule, wherein an exchange factor is bound to the MHC molecules. Exchange factors include, e.g., dipeptides such as GL, GF, GR, etc. Proto-antigen-presenting surfaces can be used to rapidly prepare antigen-presenting surfaces comprising one or more peptide antigens of interest by contacting the proto-antigen-presenting surface with one or more peptide antigens so as to displace the exchange factor. As such, the disclosure facilitates rapid evaluation of the immunogenicity of peptide antigens for activating T lymphocytes.

Abstract: A system for operating an electrokinetic device includes a support configured to hold and operatively couple with the electrokinetic device, an integrated electrical signal generation subsystem configured to apply a biasing voltage across a pair of electrodes in the electrokinetic device, and a light modulating subsystem configured to emit structured light onto the electrokinetic device. The system can further include a thermally controlled flow controller, and/or be configured to measure impedance across the electrokinetic device. The system can be a light microscope, including an optical train. The system can further include a light pipe, which can be part of the light modulating system, and which can be configured to supply light of substantially uniform intensity to the light modulating system or directly to the optical train.

Abstract: Incubators including an enclosure with an internal chamber configured to support a cell culture plate comprising a plurality of wells are disclosed. The enclosure includes a plurality of openings configured to allow access to the wells. The incubators include a sealing element configured to seal the plurality of openings in the enclosure. The sealing element comprises a plurality of openings corresponding to at least a subset of the plurality of openings in the enclosure. Access to the internal chamber can be provided by aligning the plurality of openings in the sealing element with the plurality of openings in the enclosure. Methods for using the incubators are also provided.

Abstract: Incubators are disclosed which include an enclosure with an internal chamber configured to support a cell culture plate and provide an environment suitable for maintaining and/or culturing biological cells. The enclosure can include one or more openings configured to allow access to the cell culture plate. The incubators can further include a structure having a plurality of openings configured to be aligned with a corresponding plurality of wells in the cell culture plate, and a sealing element configured to moveably seal the plurality of openings in the structure. The sealing element can comprise a plurality of openings corresponding to at least a subset of the plurality of openings of the structure. Access to the internal chamber can be provided by aligning the plurality of openings in the sealing element with the plurality of openings in the structure. Methods for using the incubators are also provided.

Abstract: Incubators including an enclosure with an internal chamber configured to support a cell culture plate comprising a plurality of wells are disclosed. The enclosure includes a plurality of openings configured to allow access to the wells. The incubators include a sealing element configured to seal the plurality of openings in the enclosure. The sealing element comprises a plurality of openings corresponding to at least a subset of the plurality of openings in the enclosure. Access to the internal chamber can be provided by aligning the plurality of openings in the sealing element with the plurality of openings in the enclosure. Methods for using the incubators are also provided.

Abstract: A system for operating an electrokinetic device includes a support configured to hold and operatively couple with the electrokinetic device, an integrated electrical signal generation subsystem configured to apply a biasing voltage across a pair of electrodes in the electrokinetic device, and a light modulating subsystem configured to emit structured light onto the electrokinetic device. The system can further include a thermally controlled flow controller, and/or be configured to measure impedance across the electrokinetic device. The system can be a light microscope, including an optical train. The system can further include a light pipe, which can be part of the light modulating subsystem, and which can be configured to supply light of substantially uniform intensity to the light modulating subsystem or directly to the optical train.

Abstract: A microfluidic device can comprise a plurality of interconnected microfluidic elements. A plurality of actuators can be positioned abutting, immediately adjacent to, and/or attached to deformable surfaces of the microfluidic elements. The actuators can be selectively actuated and de-actuated to create directed flows of a fluidic medium in the microfluidic (or nanofluidic) device. Further, the actuators can be selectively actuated and de-actuated to create localized flows of a fluidic medium in the microfluidic device to move reagents and/or micro-objects in the microfluidic device.

Abstract: A microfluidic device can comprise a plurality of interconnected microfluidic elements. A plurality of actuators can be positioned abutting, immediately adjacent to, and/or attached to deformable surfaces of the microfluidic elements. The actuators can be selectively actuated and de-actuated to create directed flows of a fluidic medium in the microfluidic (or nanofluidic) device. Further, the actuators can be selectively actuated and de-actuated to create localized flows of a fluidic medium in the microfluidic device to move reagents and/or micro-objects in the microfluidic device.

Abstract: Apparatuses and methods are described for the use of optically driven bubble, convective and displacing fluidic flow to provide motive force in microfluidic devices. Alternative motive modalities are useful to selectively dislodge and displace micro-objects, including biological cells, from a variety of locations within the enclosure of a microfluidic device.

Abstract: A microfluidic device can comprise a plurality of interconnected microfluidic elements. A plurality of actuators can be positioned abutting, immediately adjacent to, and/or attached to deformable surfaces of the microfluidic elements. The actuators can be selectively actuated and de-actuated to create directed flows of a fluidic medium in the microfluidic (or nanofluidic) device. Further, the actuators can be selectively actuated and de-actuated to create localized flows of a fluidic medium in the microfluidic device to move reagents and/or micro-objects in the microfluidic device.

Abstract: In situ-generated microfluidic isolation structures incorporating a solidified polymer network, methods of preparation and use, compositions and kits therefor are described. The ability to introduce in real time, a variety of isolating structures including pens and barriers offers improved methods of micro-object manipulation in microfluidic devices. The in situ-generated isolation structures may be permanently or temporarily installed.

Abstract: Incubators including an enclosure with an internal chamber configured to support a cell culture plate comprising a plurality of wells are disclosed. The enclosure includes a plurality of openings configured to allow access to the wells. The incubators include a sealing element configured to seal the plurality of openings in the enclosure. The sealing element comprises a plurality of openings corresponding to at least a subset of the plurality of openings in the enclosure. Access to the internal chamber can be provided by aligning the plurality of openings in the sealing element with the plurality of openings in the enclosure. Methods for using the incubators are also provided.

Abstract: A method of processing and storing biological cells includes introducing a flowable medium into a microfluidic device, the flowable medium including biological cells; sequestering one or more biological cells from the flowable medium in one or more isolation regions of the microfluidic device; and freezing the microfluidic device including the one or more biological cells sequestered therein.

Abstract: Systems, methods and kits are described for culturing one or more biological cells in a microfluidic device, including provision of nutrients and gaseous components configured to enhance cell growth, viability, portability, or any combination thereof. In some embodiments, culturing a single cell may produce a clonal population in the microfluidic device.

Abstract: A system for operating an electrokinetic device includes a support configured to hold and operatively couple with the electrokinetic device, an integrated electrical signal generation subsystem configured to apply a biasing voltage across a pair of electrodes in the electrokinetic device, and a light modulating subsystem configured to emit structured light onto the electrokinetic device. The system can further include a thermally controlled flow controller, and/or be configured to measure impedance across the electrokinetic device. The system can be a light microscope, including an optical train. The system can further include a light pipe, which can be part of the light modulating subsystem, and which can be configured to supply light of substantially uniform intensity to the light modulating subsystem or directly to the optical train.

Abstract: A microfluidic device can comprise a plurality of interconnected microfluidic elements. A plurality of actuators can be positioned abutting, immediately adjacent to, and/or attached to deformable surfaces of the microfluidic elements. The actuators can be selectively actuated and de-actuated to create directed flows of a fluidic medium in the microfluidic (or nanofluidic) device. Further, the actuators can be selectively actuated and de-actuated to create localized flows of a fluidic medium in the microfluidic device to move reagents and/or micro-objects in the microfluidic device.

Abstract: A microelectronic probe element can include a base, a tip, and a spring assembly coupled between the tip and the base. The spring assembly can include a first spring and a second spring, wherein the first spring has a negative stiffness over a predefined displacement range and the second spring has a positive stiffness over the predefined displacement range. The first spring and second spring can be coupled so that the negative stiffness and positive stiffness substantially cancel to produce a net stiffness of the tip relative to the base over the predefined displacement range.

Abstract: A stiffener assembly for use with testing devices is provided herein. In some embodiments, a stiffener assembly for use with testing devices can be part of a probe card assembly that can include a stiffener assembly comprising an upper stiffener coupled to a plurality of lower stiffeners; and a substrate constrained between the upper stiffener and the plurality of lower stiffeners, the stiffener assembly restricting non-planar flex of the substrate while facilitating radial movement of the substrate with respect to the stiffener assembly.

Abstract: A microelectronic probe element can include a base, a tip, and a spring assembly coupled between the tip and the base. The spring assembly can include a first spring and a second spring, wherein the first spring has a negative stiffness over a predefined displacement range and the second spring has a positive stiffness over the predefined displacement range. The first spring and second spring can be coupled so that the negative stiffness and positive stiffness substantially cancel to produce a net stiffness of the tip relative to the base over the predefined displacement range.

Abstract: A stiffener assembly for use with testing devices is provided herein. In some embodiments, a stiffener for use with testing devices includes an inner member; an outer member disposed in a predominantly spaced apart relation to the inner member; and a plurality of alignment mechanisms for orienting the inner and outer members with respect to each other, wherein the alignment mechanisms transfer forces applied to a lower surface of the inner member to the outer member and provide the predominant conductive heat transfer passageway between the inner and outer members.