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Tressler, C. M.

Publications and source records attributed to Tressler, C. M..

3 recordsLinked to original sources

Simian Immunodeficiency Virus and Antiretroviral Therapy Impact Rhesus Macaque Brain Lipid Distribution

Human immunodeficiency virus (HIV) infection promotes considerable bioenergetic, spatially heterogenous strain to the brain that is incompletely ameliorated through viral suppression afforded by antiretroviral therapy (ART). Disrupted homeostasis of brain lipids after HIV in humans or simian immunodeficiency virus (SIV) infection in rhesus macaques occurs due to elevated energetic demands, neuroinflammation, reactive oxygen species, and barrier leakiness. Brain lipids are particularly vulnerable to HIV-associated dysregulation due to their high abundance, unique composition, and specialized functional roles. Using rhesus macaques exposed to SIV and ART (tenofovir disoproxil fumarate (TDF), emtricitabine (FTC), and dolutegravir (DTG), we investigated the spatial distribution and abundance of lipids across brain regions and metabolically relevant peripheral tissues using mass spectrometry imaging. When comparing lipid abundance, individual lipids representing a multitude of species were more varied across tissues than by treatment condition. Further, we discerned either solely SIV infection or ART outweighed one another in altering phospholipids in different tissues Presence of ART had a greater influence on phospholipid homeostasis in the temporal cortex and hippocampus than in the midbrain, possibly due to differences in penetrance and turnover of ART across brain regions. Overall, these data demonstrate ART robustly increased phospholipids across brain regions while SIV infection had a varied impact depending on the brain region. These findings inform the need to further evaluate the neurologic consequences that may result in the brain due to disrupted lipid homeostasis across ART regimens.

pharmacology and toxicology↗

FluoMALDI microscopy: matrix co-crystallization simultaneously enhances fluorescence and MALDI imaging

We report that co-crystallization of fluorophores with matrix-assisted laser desorption/ionization (MALDI) imaging matrices significantly enhances fluorophore brightness up to 79-fold, enabling the amplification of innate tissue autofluorescence. This discovery facilitates FluoMALDI, the imaging of the same biological sample by both fluorescence microscopy and MALDI imaging. Our approach combines the high spatial resolution and specific labeling capabilities of fluorescence microscopy with the inherently multiplexed, versatile imaging capabilities of MALDI imaging. This new paradigm eliminates the notion that MALDI matrices obscure and obstruct optical microscopy approaches, allowing to image the exact same cells in tissues, free of any physical changes between fluorescence and MALDI imaging, which minimizes data registration processes. Matrix-fluorophore co-crystallization also facilitates applications with insufficient fluorescence brightness. We showcase the capabilities of FluoMALDI imaging with endogenous and exogenous fluorophores and autofluorescence-based FluoMALDI of brain and kidney tissue sections. FluoMALDI will advance structural-functional microscopic imaging in cell biology, biomedicine, and pathology.

biochemistry↗

RaMALDI: enabling simultaneous Raman and MALDI imaging of the same tissue section

Multimodal tissue imaging techniques that integrate two complementary modalities are powerful discovery tools for unraveling biological processes and identifying biomarkers of disease. Combining Raman spectroscopic imaging (RSI) and matrix-assisted laser-desorption/ionization (MALDI) mass spectrometry imaging (MSI) to obtain fused images with the advantages of both modalities has the potential of providing spatially resolved, sensitive, and specific biomolecular information, but has so far involved two separate, consecutive tissue sections for RSI and MALDI MSI, resulting in images from two separate entities with inherent disparities. We have developed RaMALDI, a streamlined, integrated, multimodal imaging workflow of RSI and MALDI MSI, performed on a single tissue section with one sample preparation protocol. We show that RaMALDI imaging of various tissues effectively integrates molecular information acquired from both RSI and MALDI MSI of the same sample. Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/539107v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@1829ccaorg.highwire.dtl.DTLVardef@3d018org.highwire.dtl.DTLVardef@531015org.highwire.dtl.DTLVardef@144f1a3_HPS_FORMAT_FIGEXP M_FIG C_FIG We demonstrate for the first time RaMALDI imaging, a streamlined, integrated multimodal imaging workflow of Raman spectroscopy imaging (RSI) and matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI), which is performed on a single sample and uses one sample preparation protocol. RaMALDI imaging of various tissues effectively integrates molecular information acquired from both RSI and MALDI MSI of the same sample.

bioengineering↗