Lipidomics of Leprosy and Tuberculosis in Prehistoric Southeast Asia: Establishing a Framework for Biomolecular Palaeopathology in Tropical Environments

Nicola Czaplinski1*, Gerard Hoyne1, Monika Tschochner1, and Melandri Vlok2

Despite affecting millions of people today, the long-term history of tuberculosis (TB) and leprosy in Southeast Asia remains poorly understood. Archaeological evidence of these diseases in the region is limited, in part because tropical environments pose major challenges for biomolecular preservation. Heat and humidity accelerate the degradation of ancient DNA (aDNA), restricting the use of conventional molecular methods for identifying pathogens in archaeological remains. This presentation explores lipidomic analysis as an alternative approach to detect ancient mycobacterial infection. Lipids are abundant components of the cell walls of Mycobacterium leprae and the Mycobacterium tuberculosis complex (MTBC). Their hydrophobic properties make them more resistant to environmental degradation than DNA, allowing them to persist in skeletal material from challenging tropical contexts. Consequently, pathogen derived lipids may represent a promising biomarker in the identification of TB and leprosy in Southeast Asian archaeological remains. This presentation introduces a current PhD project investigating lipidomic approaches for detecting ancient mycobacterial disease in Southeast Asia. This project will analyse human skeletal remains exhibiting macroscopic indicators consistent with TB and/or leprosy from archaeological sites in Vietnam (n=9; 7000-1800BP), Thailand (n=4; 2300-1500BP), and Indonesia (n=2; ~3000BP). Prior to analysing these ancestral remains, lipid extraction protocols will be refined using pre-modern skeletal samples from Thailand (n=5; ~150BP) with documented cases of TB and leprosy. By developing minimally invasive lipidomic methods suited to tropical preservation conditions, this research seeks to expands biomolecular palaeopathology in Southeast Asia, and to provide new insights into the long-term presence of TB and leprosy in the region.