Correlative microscale mapping of human meniscus biomechanics and biochemistry by AFM micro-indentation and MALDI-FTICR mass spectrometry imaging

Abstract

Meniscus degeneration is a key contributor to knee osteoarthritis (OA), yet the spatial relationship between microscale mechanical properties and molecular composition remains insufficiently defined [1]. The meniscus exhibits zonal heterogeneity comprising red–red (RR), red–white (RW), and white–white (WW) regions with distinct vascularization, extracellular matrix (ECM) organization, and biomechanical roles. How OA alters this structure–function relationship at microscale resolution is unclear. We established a correlative workflow combining atomic force microscopy (AFM) micro-indentation and MALDI-FTICR mass spectrometry imaging (MSI) to analyze matched cryosections from osteoarthritic and age-matched healthy donor menisci.