Microarrays for the Immune System

When a disease or infection takes hold in the human body, doctors sometimes have difficulty diagnosing a patient before there are observable symptoms. During early pathogenesis (when the body is challenged by disease or infection) the immune system is critical for mediating the physiological response to the challenge. Monitoring the cellular response of the immune system can provide a wealth of information about how the body responds to different medical conditions.

One way to observe the cellular response to these conditions is to analyze the presence of the cells that react to antigens (any substance that elicits an immune response from the body). The cells primarily responsible for the antigen-specific cellular immune response are T cells. As a T cell matures, it is programmed to recognize a distinct antigen, and in the future, it facilitates the immune system recognition of the same antigen. The T cell population in every person is diverse and analyzing the presence of T cells responsive to an antigen is critical for characterization of the cellular immune response.

Therefore, characterizing a broad spectrum of T cells in the blood system can provide insight into the state of the immune response. Pat Brown, Mark Davis and colleagues developed a system to detect antigen-specific T cells by their ability to recognize and bind to synthetic antigens. With this novel technology, a single microarray chip can hold up to 1000 synthetic antigens. This array allows rapid isolation and analysis of multiple antigen-specific T cell populations. The Stanford researchers demonstrated the specificity and sensitivity of this assay with multiple prototypes - less than 0.1% T cell population within the sample is required for detection. Using this system, T cells are simply applied to the array and given 10 minutes to identify and attach to the antigens they recognize on the array. Next, the T cells that didn’t recognize any antigens are washed away, and those left on the chip are analyzed with an automated reader. Once immobilized, scientists can inspect the T cells by microscopy, characterize the cells by immunostaining, or analyze their responsiveness to mediators of activation.

Additionally, the technique has been successfully utilized with mouse and human clinical samples from blood, tissue, and culture. This system can also be used to discover antigens in infectious disease, autoimmunity, and cancer. Furthermore, it can be used for tracking the immune response to vaccines or screening for exposure to viruses, bacteria and other biowarfare agents. This approach may provide a practical way to screen for natural immune responses and to characterize variations in the T cell repertoire in healthy individuals compared to patients with various diseases.

If you are interested in learning more about the licensing opportunities for the antigen-array technology for the detection and characterization of cellular immune response, contact Luis Mejia at luis.mejia@stanford.edu or (650) 723-0651.