For the second time in three years – Banff, Alberta once again acted as the hub for immunologists across the nation for the 32nd Annual Spring Meeting of the Canadian Society for Immunology (CSI), that took place from April 12 – 15. The picturesque views at the Banff Centre, provided by the surrounding Rocky Mountains, were only outshone by the talented array of expert immunologists who engaged the audience with exciting and novel research. A huge thank you goes to the local organizing committee chair Dr. John Gordon and his team from the University of Saskatchewan for putting together a wonderful few days of impactful research and evening socials.
This year’s CSI keynote speaker, Dr. Shannon Turley (Genentech), opened the minds of many to the expanding world of stromal cells during different contexts of immunity. Using unbiased single-cell RNA sequencing analyses, her group identified several distinct cancer-associated fibroblast populations, with one particular subset expressing much higher levels of TGF-β, a correlate with poor patient outcomes to atezolimumab (α-PDL1) treatment. These findings provided a new predictor to cancer patient outcomes, as well as a novel cellular and molecular pathway for therapeutic targeting.
In her subsequent story, her group identified unique stromal cell sub-clusters in mice that each locally instructed different myeloid transcriptional programs, such as dendritic cells or large cavity macrophages. Understanding how this stromal-immune cell instruction paradigm applies to other tissue resident immune cells provides a new view on the local control of innate/adaptive immunity by non-lymphoid cells.
Diet & Immunity
The first symposium discussed how dietary modulations can have a profound influence on immune responses. Dr. Eric Martens (University of Michigan) explained the importance of dietary fibre on shaping the different populations of gut microbes to form a functional colonic mucus barrier and reduce pathogen susceptibility during infection. Furthermore, he discussed the interplay between IL-10 and spontaneous colitis with relation to weight loss and high/low fibre diets, with his final message being “Eat your Canadian oat-based cereal!”. Dr. Catherine Field (University of Alberta) spoke about the influence of DHA, an omega-3 fat naturally plenty in fish, on the developing infant immune system and how it programs immune cell profiles depending on the time of intake during pregnancy. She finished her talk with an informative conversation on controlling for nutrition during rodent studies.
Next up, Dr. Eugene Chang (University of Chicago) uncovered new roles for peptide YY, a neuropeptide locally produced in the gut by Paneth cells upon food intake, that include restricting obesity and protection against fungal infections. The Diet & Immunity symposium was concluded with a fantastic lecture by Dr. Elena Verdu (McMaster University), who explored how the intestinal microbiome and associated bacterial proteases influence the innate and adaptive immune responses in controlling Celiac disease pathogenesis.
The second symposium emphasized the importance of understanding how the immune system is regulated. Dr. Rachael Clark (Harvard University) talked about the differential role of tissue-resident versus systemic recirculating T cells in human inflammatory skin diseases. Dr. Clark demonstrated that patients with mycosis fungoides display localized inflammatory lesions that are populated by tissue-resident memory T (TRM) cells, whereas leukemic cutaneous T cell lymphoma (CTCL) is a disease of inflammatory central memory T (TCM) cells that recirculates between blood and skin. Her work highlights the importance of bedside-to-bench translational research approaches. Dr. Megan Levings (University of British Columbia) investigated the role of regulatory T cells (Tregs) in reducing inflammation in visceral adipose tissue (VAT) of obese mice. Interestingly, Dr. Levings saw a differential role of Interleukin-33 in inducing Tregs in mouse compared to humans, emphasizing the challenges of using murine systems to model human disease. Dr. Brad Nelson (University of British Columbia) sampled different metastatic sites in the peritoneum of patients with high-grade serous ovarian carcinoma to understand spatial dynamics of immune system in impacting clonal diversity of tumour.
Next, Dr. Sarah Crome (University of Toronto) talked about preliminary findings of innate lymphoid cells (ILCs) and potential immune regulatory effects in kidney transplantation. She highlights the importance of optimizing enzymatic digestion protocols to reduce biases in immunophenotyping of human tissues. Dr. Florent Ginhoux (Singapore Immunology Network) gave a wonderful lecture on the “immune landscape” of myeloid cells. To provide a single standardized paradigm of myeloid cell ontogeny, Dr. Ginhoux used unsupervised single-cell RNA sequencing (scRNA-seq) to resolve heterogeneity of monocytes, macrophages, conventional and plasmacytoid dendritic cells, and their precursors. He concluded by mentioning the challenges and caveats of using scRNA-seq to study human immunology.
The last symposium of the conference covered what some scientists will claim as ‘The Final Frontier of science’ … The brain! Dr. Shannon Dunn (University of Toronto) opens the symposium by demonstrating interactions between adolescent obesity in women and risk of developing multiple sclerosis. She further noted the importance of sex in disease etiology of mice with experimental autoimmune encephalomyelitis (EAE). Dr. Joan Goverman (University of Washington) showed that in a model of EAE that was traditionally thought of a CD4+ T cell mediated disease, CD8+ T cells exacerbated inflammation in central nervous system (CNS). She further demonstrated that interferon-gamma secreted by CD8+ T cells increased susceptibility of oligodendrocyte from undergoing Fas/FasL-mediated cell death, preventing remyelination. Dr. Francisco Quintana (Harvard University) investigated the role of microbial metabolites in modulating astrocyte activity in the central nervous system (CNS). Dr. Quintana found that dietary tryptophan was metabolized into aryl hydrocarbon receptor (AHR) ligands, inducing astrocytes to secrete type I interferons in EAE.
Next, Dr. V. Wee Yong (University of Calgary) explored the beneficial effects of inflammatory responses in the brain following injury to CNS. Interestingly, stimulation of macrophages, monocytes, and microglia in vivo promotes remyelination in spinal cord injury murine model. Dr. Yong also discusses the impact of extracellular matrix molecules on oligodendrocytes and remyelination. Dr. Jennifer Gommerman (University of Toronto) presented her recent work in understanding the role of gut-derived immunoglobulin A (IgA) positive plasma cells in reducing inflammation in CNS of mice with EAE. Furthermore, colonization of protists Trichomonas musculis reduces EAE severity by inducing IgA+ plasma cells encouraging future research in modulating gut microbes in patients with neuroinflammatory diseases.
In addition to the CSI symposiums, we heard fantastic talks from CIHR-III Bhagirath Singh Award Recipients (2017) Dr. Arthur Mortha (University of Toronto) and Dr. Marceline Côté (University of Ottawa).
We would like to thank the generous donations and exciting new updates from CSI 2019 sponsors: Gold sponsors (BioLegend), Silver sponsors (Miltenyi Biotec Inc., StemCell Technologies Inc), Bronze sponsors (BD/FlowJo, Sony Biotechnology), and General sponsors (Cedarlane Laboratories Ltd, CIHR – Institute of Infection and Immunity, University of Saskatchewan).
Congratulations to Dr. Jean Marshall (Dalhousie University) for receiving the Bernhard Cinader Award for her exceptional scientific and leadership contributions to the immunology community. Dr. Marshall took us through her interesting adventures in studying the role of mast cells in defence against infection, chronic inflammatory diseases and cancer. This years CSI investigator Award goes to Dr. Alberto Martin (University of Toronto), and the CSI New Investigator Award goes to Dr. Bebhinn Treanor (University of Toronto). Furthermore, congratulations to all the travel and poster award winners.
Big thanks to the incredible local organizing committee from the University of Saskatchewan including Dr. John Gordon (Chair), Dr. Gurpreet Aulakh, Dr. Julia Montgomery, Dr. Heather Wilson, Jessica Brocos-Duda, Ghassan Al-Yassin, and Brodie Deluco.
Douglas: As we conclude our reflections of another successful annual CSI meeting, may we forever remember the gorgeous Banff rocky mountains, unforgettable scenic sunsets, and occasional elk that we stumbled upon in CSI 2019. Albert: Doug, you MAST have forgotten we were at a scientific conference and not on vacation. In any case, if you’re itching for another amazing immunological conference join us at The Hotel Chéribourg, Orford, Quebec for the 33rd Annual Canadian Society for Immunology Meeting on June 5-8, 2020.