MSD Preclinical Toxicology Panel — Liver, Kidney & Cardiac Safety Biomarkers

The minimum recommended panel set for broad-coverage preclinical safety includes: Liver Injury Panel 1 (ARG1 + GST-α — detects hepatocellular injury with organ specificity and early kinetics that ALT/AST cannot match), Kidney Injury Panel 1 or 2 (KIM-1 + NGAL ± Clusterin ± Cystatin C — tubular and glomerular injury coverage), and Cardiac Injury Panel 2 (cTnI + cTnT + FABP3 — myocardial injury with translational troponins). For compounds with known or suspected muscle toxicity, add Muscle Injury Panel 1 (cTnI + cTnT + sTnI + FABP3 + Myl3) to discriminate skeletal vs. cardiac injury. The Acute Phase Protein Panel (A2M + AGP) and Inflammation Panel 1 (MCP-1 + TIMP-1 + TSP-1) provide systemic context — useful for immunomodulatory compounds or when organ injury is accompanied by inflammatory response. All panels total ~175-225 µL EDTA plasma. For specific compound classes, we recommend discussing known target organ toxicities during project consultation to select the most informative panel combination. All services are for research use only.

Traditional clinical chemistry markers have fundamental limitations that MSD organ-specific panels address: ALT/AST lack liver specificity — AST is ubiquitous (muscle, heart, kidney, RBCs); ALT is also in muscle and kidney. Elevated AST/ALT in a preclinical study could reflect hepatotoxicity, muscle injury from restraint or injection, or both — requiring histopathology to resolve. Arginase-1 is liver-exclusive. BUN and creatinine are insensitive — they rise only after >50% nephron loss, detecting severe but not mild/moderate kidney injury. KIM-1 and NGAL rise within hours of tubular insult, before functional impairment. Traditional markers are temporally delayed — ALT/AST peak at 24-48 hours post-insult; GST-α and ARG1 peak earlier. BUN/Cr rise days after nephrotoxic insult; KIM-1 rises at 6-24 hours. MSD organ-specific panels complement, not replace, clinical chemistry — the combination of early, organ-specific biomarkers (MSD) with established functional markers (chemistry) provides the most complete preclinical safety picture.

The MSD preclinical toxicology panels are primarily configured for rat and mouse. Human organ injury markers are available as individual U-PLEX or R-PLEX assays rather than pre-configured MULTI-SPOT panels. For translational toxicology studies, researchers commonly use MSD rat panels for preclinical regulatory toxicology and then bridge to human biomarkers using MSD U-PLEX custom panels — measuring the same analytes in human samples with the same ECL detection technology. This platform consistency (same detection chemistry, same instrument) reduces translational variability compared to bridging from rat MSD to human ELISA or clinical chemistry. Human kidney markers available via U-PLEX include KIM-1, NGAL, Clusterin, Cystatin C, Osteopontin, IL-18, and IP-10. Human liver markers include ARG1 and GST-α. Human cardiac markers include cTnI, cTnT, FABP3, and NT-proBNP. We can configure species-matched custom panels for translational biomarker programs — contact us to discuss your specific analytes and species requirements. All services are for research use only.

This is a critical question in preclinical toxicology because many compounds — particularly statins, fibrates, and certain kinase inhibitors — can cause both skeletal myotoxicity and cardiotoxicity. Standard cardiac troponin I (cTnI) is expressed in both cardiac and skeletal muscle (though at much lower levels in skeletal muscle), making it impossible to determine whether an elevated cTnI reflects myocardial or skeletal muscle injury from cTnI measurement alone. The MSD Muscle Injury Panels (1 and 3) include sTnI — slow-twitch skeletal troponin I — alongside cTnI, cTnT, FABP3, and Myl3. sTnI is expressed exclusively in skeletal muscle. The interpretation logic: cTnI elevated + sTnI normal = cardiac injury (myocardial-specific). cTnI elevated + sTnI elevated = skeletal muscle injury (± concurrent cardiac involvement — evaluate cTnT trend). sTnI elevated + cTnI normal = isolated skeletal muscle injury. This discrimination has previously been possible only through histopathology or isoform-specific immunohistochemistry. Myl3 (myosin light chain 3) and FABP3 provide additional muscle injury signals but are expressed in both cardiac and skeletal muscle — useful for injury magnitude quantification rather than tissue origin discrimination. For research use only.

Standardized pre-analytical handling is critical for multi-organ biomarker studies because different biomarkers have different ex vivo stability profiles. Recommendations: Matrix: EDTA plasma is strongly preferred for MSD organ injury panels — KIM-1, NGAL, and GST-α can show artifactually elevated levels in serum due to platelet activation during clotting. If serum is required (e.g., for concurrent clinical chemistry), process within 30 minutes at room temperature. Processing: centrifuge at 2000×g for 10 minutes at 4°C within 1 hour of collection. Aliquot immediately — do not store samples in the primary collection tube (analyte adsorption to tube walls). Aliquot volume: 35 µL per planned panel (25 µL assay + 10 µL dead volume). Label aliquots with timepoint, animal ID, and intended panel. Storage: -80°C immediately after aliquoting. Avoid -20°C storage — some biomarkers (KIM-1, Clusterin) show degradation at -20°C over >2 weeks. Freeze-thaw: single freeze-thaw cycle only — aliquot such that each panel run uses a fresh, never-thawed aliquot. Timepoint design: pre-dose (baseline), early (2-6h for GST-α and KIM-1), peak injury (24-48h), recovery (72h-Day 7). Include a pre-dose baseline for every animal — fold-change from baseline is more informative than absolute concentration for organ injury assessment. These recommendations are for research purposes only.