Evaluation of serum protein electrophoresis and immunofixation in dogs seropositive for various vector-borne pathogens

Oriol Jornet-Rius; Nida Chornarm; Niki Skeldon; Ashley McGrew; Michael Lappin; Laia Solano-Gallego; A Russell Moore

doi:10.1111/vcp.13399

Evaluation of serum protein electrophoresis and immunofixation in dogs seropositive for various vector-borne pathogens

Vet Clin Pathol. 2024 Nov 11. doi: 10.1111/vcp.13399. Online ahead of print.

Authors

Oriol Jornet-Rius¹, Nida Chornarm², Niki Skeldon³, Ashley McGrew⁴, Michael Lappin², Laia Solano-Gallego¹, A Russell Moore⁴

Affiliations

¹ Departament de Medicina i Cirurgia Animals Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
² Center for Companion Animal Studies, Department of Clinical Sciences, Colorado State University, Fort Collins, Colorado, USA.
³ Axiom Veterinary Laboratories Ltd, Newton Abbot, Devon, UK.
⁴ Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA.

PMID: 39528734
DOI: 10.1111/vcp.13399

Abstract

Background: Canine vector-borne diseases (VBDs) induce non-specific dysproteinemias, detectable by serum protein electrophoresis (SPE). VBDs have been reported to induce a monoclonal gammopathy pattern. Monoclonal gammopathies are commonly the result of paraprotein (M-protein) produced by an immunoglobulin-secreting neoplasm.

Objectives: The aims of this study were to characterize and compare SPE and immunofixation (IF) changes, evaluate the performance of previously identified SPE and IF interpretative criteria, and identify M-proteins in a cohort of dogs seropositive for a VBD and with an unknown history for an immunoglobulin-secreting neoplasm.

Methods: A total of 143 serum samples from dogs that tested seropositive for different vector-borne pathogens were assessed by SPE. Cases with abnormal globulin fractions were further characterized by IF. Protein fraction and IF labeling results were evaluated using Kruskal-Wallis with Dunn's multiple comparisons and principal component analysis (PCA).

Results: IF was performed in 112 VBD-seropositive samples with dysproteinemia evaluated by SPE. Most (84/112, 75%) had a polyclonal expansion. Only two dogs had findings suggestive of an M-protein when considering both SPE and immunofixation. PCA clustered E.canis/A.phagocytophilum and B.gibsoni/CM.haematoparvum groups with relatively more γ-globulins than albumin and α-globulins, and the B.gibsoni/CM.haematoparvum group with more prominent IgA and IgM labeling than IgG labeling. Additionally, D.immitis clustered with more prominent β-globulins than γ-globulins and more IgG4 than IgG-FC.

Conclusions: The previously derived interpretative criteria suggested an M-protein in very few VBD-seropositive dogs. PCA identified SPE and immunofixation pattern differences between dogs seropositive for different infectious agents.

Keywords: Dirofilaria spp.; Ehrlichia spp.; Leishmania spp.; M‐protein; dysproteinemia; infectious disease; monoclonal gammopathy; neoplasia; paraproteinemia.