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Congrats Adam on your Cell paper

Researchers create “Lipidomic Map,” offering insights into immunology

An international team of scientists has developed a method for simultaneously detecting thousands of lipid molecules that are displayed to T cells in the human immune system.

The study, co-led by Professor D. Branch Moody, MD, of the Division of Rheumatology, Immunity and Inflammation at Brigham and Women’s Hospital, and Adam Shahine, PhD, at the Monash Biomedicine Discovery Institute represents a collaboration among researchers from Oxford, United Kingdom, Monash University in Melbourne, Australia and Groningen, Netherlands. The results were published today in Cell.

The team developed a new and sensitive method to detect more than 2,000 lipids bound to CD1 antigen presenting molecules, which display antigens to the human immune system.

While scientists have long known that T cells recognise antigens, until the 1990s, it was thought that these antigens were always peptides derived from proteins. Because lipids are not encoded by genes and are instead made by enzymes and form into membranes, they have entirely different functions and positions in the cell.

The ability to measure many lipid antigens at one time will allow future researchers to cross-check any disease-related lipid of interest to the list of candidate lipid antigens from this map and potentially make connections to diseases.

Their efforts yielded the first integrated CD1 lipidomic map, which could help guide the investigation and discovery of lipid blockers and antigens for T cells and support the view that lipids normally influence immune responses.

The research builds on earlier methods that separate cellular lipids in one chromatographic system, which provided only a limited perspective. The new structural biology work, undertaken by Dr Shahine, ARC DECRA fellow, showed how lipids fit inside proteins using size-based mechanisms.

Combined, the structures and biochemistry detail rules about the size, shape, and chemical content of the kinds of lipids that can bind CD1 and cause a T cell response—either activation or deactivation. It is the latest in a series of studies that date back to the 1990s, when Brigham scientists discovered that T cells can recognise lipid antigens.

Splashdown“. The image provides a prism for thinking about how oily antigens are recognized in aqueous solution. Four lipid presenting molecules, CD1a, CD1b, CD1c and CD1d, including a three dimensional CD1-lipid complex, fall toward the surface of a blue and watery environment surrounding a T cell. Image credit: Dr Erica Tandori.

“In this ambitious decade-long, multidisciplinary study, we have characterized the full spectrum of cellular lipids that can be displayed to T cells. Further, we have collated 25 years of structural biology data, as well as new data collected at the ANSTO Australian Synchrotron, to standardize the rules that govern the molecular mechanisms in lipid presentation” said Dr Shahine. “Our hope is that the data generated in this study will serve as a foundation for future research in the field of lipid mediated immunity.”

Professor Moody said, “The Brigham provides an environment where physicians and scientists from differing fields can collaborate. This multidisciplinary effort involved biophysical techniques related to mass spectrometry and biological techniques related to lipid chemistry. The lipids informed immunological outputs, and the mode of lipid recognition is proven through X-ray crystallography.”

Read the full publication in Cell, titled CD1 lipidomes reveal lipid-binding motifs and size-based antigen-display mechanisms

DOI: 10.1016/j.cell.2023.08.022.

Original article

Congrats to our newly appointed BDI Group Leaders: Wael, Jan and Adam

Monash BDI announce new Group Leaders

Monash Biomedicine Discovery Institute (BDI) is excited to announce 13 newly selected Group Leaders. These Group Leaders are part of a program created by Monash BDI to help early career researchers (ECRs) bridge the gap between senior postdoctoral fellow and independent lab head.

Professor Dena Lyras, Deputy Director at the Monash BDI, said that this program provides recognition and additional career momentum for researchers who are leading novel, cutting-edge research programs and developing their independence.

“Congratulations to all of the newly selected Group Leaders. This is a testament to the hard work and dedication of these researchers, and we look forward to seeing their next steps and achievements,” said Professor Lyras.

Congratulations to the newly selected Monash BDI Group Leaders:

Dr Wael Awad seeks to elucidate the mechanistic basis underpinning metabolite capture and loading of the MHC class I-related molecule “MR1” by cellular chaperones, by using cutting-edge molecular, immunological and biochemical approaches. He also explores the scope of environmental and microbial metabolites that can modulate human T cell immunity. Such studies pave the way for the development of innovative therapeutics based on selective modulation of T cell immunity.

Dr Jan Petersen’s research focuses on antimicrobial immunity and natural killer (NK) cell immunity. He investigates how T cells and NK cells recognise microbial peptide antigens presented by major histocompatibility complex (MHC) molecules, and aims to decipher the molecular mechanisms that define the ability of the adaptive immune system to distinguish between self and foreign. Focused on events central to infection and immunity, his work is aimed at understanding outcomes in various diseases and transplantation.

Dr Adam Shahine is focused on the molecular roles of lipids in the regulation and dysregulation of human adaptive immunity. Using structural biology, he seeks to investigate the mechanisms of lipid antigen recycling, and the presentation of lipid antigens by CD1 antigen presenting molecule family T cells.

Dr Deepak Adhikari aims to gain a better understanding of how mitochondria are formed and how they regulate the development of eggs and offspring.

Dr Asolina Braun aims to understand what initially causes psoriasis and hence to discover new treatments for this skin disease. Her research is focused on finding peptides that trigger and set off the detrimental immune response in psoriasis.

Dr Luke Formosa investigates how mitochondrial enzymes are built from their individual subunits, and how this process is disrupted in mitochondrial disease. One in 5,000 children will develop a mitochondrial disease, but about one-third of patients won’t have a genetic diagnosis. By discovering new genes that play a role in this process, the diagnosis of patients can be improved, paving the way for new treatments for this disease.

Dr Meiling Han’s research targets antibiotic resistance, focusing on the mechanism(s) underpinning the extensive membrane remodelling that occurs in Gram-negative bacteria and the interactions between remodelled bacterial membranes and membrane-targeting antimicrobials (e.g. lipopeptides). The fundamental mechanistic information that she generates will greatly inform the future design of much-needed antibiotics against antibiotic-resistant bacteria.

Dr Anja Knaupp’s research centres on characterising cell-type-specific sets of proteins and determining how they operate. Insight into these molecular mechanisms and drivers is key for our understanding of cellular identity and changes that, for example, occur during cancer development.

Dr Rachael Lappan aims to understand the nature and basis of microbial life in the atmosphere, the largest but most unexplored potential ecosystem on Earth. Using cutting-edge molecular and biogeochemical approaches, she aims to identify true microbial residents of the atmosphere, understand their mechanisms for survival in this environment and explore their role in seeding newly formed environments.

Dr Kate McArthur’s research uses a variety of microscopy and cell biology techniques to understand the mechanisms behind, and immune responses to, mitochondrial changes and aberrant cell death during disease.

Dr Nitin Patil is investigating peptide- and oligonucleotide-based antimicrobial drug development and delivery.

Dr Francesca Short combines genomic and molecular microbiology approaches to understand bacterial behaviour and adaptation. Her current research focuses on how bacteria control the production of virulence factors during infection and on how common disinfectants can compromise antibiotic efficacy.

Dr Yogitha Srikhanta investigates strategies that bacterial gut pathogens employ to proliferate, cause disease and survive, with a focus on antibiotic resistance and epigenetic-mediated gene regulation.

Original article