Bioluminescent Reporting of In Vivo IFN-γ Immune Responses during Infection and Autoimmunity

• Published in: The Journal of immunology (1950) Vol. 202; no. 8; pp. 2502 - 2510
• Main Authors: Reynolds, Catherine J, Chong, Deborah L W, Li, Yihan, Black, S Lucas, Cutler, Amy, Webster, Zoe, Manji, Jiten, Altmann, Daniel M, Boyton, Rosemary J
• Format: Journal Article
• Language: English
• Published: United States AAI 15.04.2019
• Subjects: Animals; Enzyme-Linked Immunospot Assay; Immunity, Cellular; Interferon-gamma - genetics; Interferon-gamma - immunology; Luminescent Measurements; Lung - immunology; Lung - pathology; Mice; Mice, Transgenic; Novel Immunological Methods; Pseudomonas aeruginosa - immunology; Pseudomonas Infections - immunology; Transgenes - immunology
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.1801453

IFN-γ is a key cytokine of innate and adaptive immunity. It is important to understand temporal changes in IFN-γ production and how these changes relate to the role of IFN-γ in diverse models of infectious and autoimmune disease, making the ability to monitor and track IFN-γ production in vivo of a substantial benefit. IFN-γ ELISPOTs have been a central methodology to measure T cell immunity for many years. In this study, we add the capacity to analyze IFN-γ responses with high sensitivity and specificity, longitudinally, in vitro and in vivo. This allows the refinement of experimental protocols because immunity can be tracked in real-time through a longitudinal approach. We have generated a novel murine IFN-γ reporter transgenic model that allows IFN-γ production to be visualized and quantified in vitro and in vivo as bioluminescence using an imaging system. At baseline, in the absence of an inflammatory stimulus, IFN-γ signal from lymphoid tissue is detectable in vivo. Reporter transgenics are used in this study to track the IFN-γ response to infection in the lung over time in vivo. The longitudinal development of the adaptive T cell immunity following immunization with Ag is identified from day 7 in vivo. Finally, we show that we are able to use this reporter transgenic to follow the onset of autoimmune T cell activation after regulatory T cell depletion in an established model of systemic autoimmunity. This IFN-γ reporter transgenic, termed "Gammaglow," offers a valuable new modality for tracking IFN-γ immunity, noninvasively and longitudinally over time.