biostudies-literatureRyan DJU.S. Department of Health and Human ServicesNIDDK NIH HHSNIAID NIH HHSBurroughs Wellcome FundNIGMS NIH HHS7578-7585https://www.ebi.ac.uk/biostudies/studies/S-EPMC6652190biostudies-literatureUnknown91(12)The ability to target discrete features within tissue using liquid surface extractions enables the identification of proteins while maintaining the spatial integrity of the sample. Here, we present a liquid extraction surface analysis (LESA) workflow, termed microLESA, that allows proteomic profiling from discrete tissue features of ∼110 μm in diameter by integrating nondestructive autofluorescence microscopy and spatially targeted liquid droplet micro-digestion. Autofluorescence microscopy provides the visualization of tissue foci without the need for chemical stains or the use of serial tissue sections. Tryptic peptides are generated from tissue foci by applying small volume droplets (∼250 pL) of enzyme onto the surface prior to LESA. The microLESA workflow reduced the diameter of the saAnalytical chemistryMicroLESA: Integrating Autofluorescence Microscopy, In Situ Micro-Digestions, and Liquid Extraction Surface Analysis for High Spatial Resolution Targeted Proteomic Studies.PMC66521905P41 GM103391-07P41 GM103391U54 DK120058R01 AI138581P30 DK058404K08AI113107K08 AI113107R01AI1325601R01 AI138581-01A1R01 AI132560Ryan DJPutnam NESpraggins JMPerry WJWilde ADCaprioli RMPatterson NHWeiss ACassat JESkaar EPfalseMicroLESA: Integrating Autofluorescence Microscopy, In Situ Micro-Digestions, and Liquid Extraction Surface Analysis for High Spatial Resolution Targeted Proteomic Studies.The ability to target discrete features within tissue using liquid surface extractions enables the identification of proteins while maintaining the spatial integrity of the sample. Here, we present a liquid extraction surface analysis (LESA) workflow, termed microLESA, that allows proteomic profiling from discrete tissue features of ∼110 μm in diameter by integrating nondestructive autofluorescence microscopy and spatially targeted liquid droplet micro-digestion. Autofluorescence microscopy provides the visualization of tissue foci without the need for chemical stains or the use of serial tissue sections. Tryptic peptides are generated from tissue foci by applying small volume droplets (∼250 pL) of enzyme onto the surface prior to LESA. The microLESA workflow reduced the diameter of the sa2019-01-01T00:00:00Z2019 Jun2026-05-04T01:12:11.772Z2020-06-21T07:02:43ZS-EPMC66521903114980810.1021/acs.analchem.8b05889