Poster Presentation: Lingzheng Shi

ABSTRACT

Extracorporeal cross-circulation coupled with Crystal Ribcage to dissect immune experience and aging in pneumonia

Linzheng Shi, Michael Vannini, Lauren Castle, Andrew Tsao, Abdulrahman Kobayter, Chanhong Min, Athanasios Batgidis, Rohin Banerji, Kathryn Regan, Gabrielle Grifno, Yuqing Deng, Jessica Daher, Byungjun Kang, Winita Wangsrikhun, Han Kahvecioglu, Catherine Ha, Elise Armstrong, Bradley Hiller, Erin Crossey, John Jiang, Mohammad Rashidian, Béla Suki, Jude Phillip, Joseph Mizgerd, Hadi Nia

Objectives: Pneumonia is a severe respiratory illness, with immune-experience and aging as key variables affecting prognosis. How pneumonia progresses in real-time and systemic  vs. pulmonary factors impact experience and aging remain poorly understood. Here, we develop extracorporeal cross-circulation coupled with Crystal Ribcage to 1) continuously probe real-time pneumonia progression at high spatiotemporal resolution, and 2) dissect the effect of aging and prior exposure to disease on pulmonary vs. systemic immunity against pneumonia.

Methods: 24-hour cross-circulation was established between awake “donor” mouse and ex-vivo “recipient” lungs imaged under Crystal Ribcage during infection. Pulmonary vs. systemic immunity was dissected by mismatching experience vs. naive backgrounds between donors vs. recipients, with intact vs. depleted lung-resident CD4+ T-cells, analyzed via immunohistochemistry and immunofluorescence. Trained alveolar macrophage dynamics were investigated by mismatching immune-experience between double recipients linked to single immune-naïve donors. Double donors with mismatched young vs. old age, with distinct pan-leukocyte fluorescent-labels, were cross-circulated into single recipient to investigate aging effect on systemic immunity.

Results/Conclusion: We established long-term immunogenic cross-circulation between donor and recipient (Fig.A) to image 24-hours of pneumonia during which neutrophils are recruited intra-alveolar and cluster to combat infection (Fig.B,C).  By mismatching experience vs. naïve immunity between donor vs. recipients, we reveal experienced pulmonary factors alone generate a significant immune response against pneumonia (Fig.D), with resident CD4+ T-cells central to this trained immunity (Fig.E), in contrast to systemic factors. Linking immune-naïve donor with double recipients of mismatched pulmonary immunity (Fig.F) shows trained alveolar macrophages exhibit amplified responses to infection, vs. naive (Fig.G-I). Mismatching double donor circulations of old- vs. young-backgrounds, with distinct pan-leukocyte labels (Fig.J), we reveal young systemic factors are heavily recruited to combat infection, compared to aged. Altogether, our model enables the first longitudinal cellular-resolution study to dissect the effects of immune experience and aging on diseases affecting the lung.