Analysis of Intestinal Tissue Biopsies from Cats with Chronic Enteropathy Using Mass Spectrometry Imaging

Abstract:

Background: Mass spectrometry imaging (MSI) captures the spatial distribution and abundance of molecules within tissue specimens and highlights distinct molecular signatures. In human medicine, MSI has been used to differentiate benign from malignant lesions and for tumor classification.

Hypothesis/

Objectives: To identify molecular patterns within the small intestinal mucosa of healthy cats compared with cats diagnosed with lymphoplasmacytic enteritis (LPE) or low-grade intestinal T-cell lymphoma (LGITL).

Animals: Formalin-fixed, paraffin-embedded (FFPE) small intestinal tissue biopsy specimens from 9 healthy cats, 26 cats with LPE, and 25 cats with LGITL.

Methods: Retrospective study. Metabolites within the mucosal layer of the small intestinal tract were captured using standardized protocols for MSI. Results were compared using Wilcoxon rank-sum test, with results expressed as false discovery rate-corrected P-values. Statistical significance was defined as P ≤ 0.05.

Results: Of the 225 named metabolites identified by MSI, 121 differed significantly between mucosal biopsy specimens from healthy cats and those from cats with LGITL. Metabolites associated with membrane biosynthesis, cellular energy metabolism, and oxidative stress responses including phosphoethanolamine (P = 0.02), adenosine monophosphate (P = 0.03), taurine (P = 0.03), and glutathione (P = 0.04) were more abundant in the mucosa of cats with LGITL compared with healthy controls. No significant differences were detected between biopsy specimens from cats diagnosed with LPE or LGITL.

Conclusions and Clinical Importance: These findings are consistent with prior studies in cats and other species and suggest shared metabolic alterations in chronic enteropathies. Identified pathways may represent future diagnostic biomarkers and potential therapeutic targets.