Background: Genes associated with patient response in dogs with immune-mediated hemolytic anemia (IMHA) could serve as biomarkers of disease but are poorly characterized.
Hypothesis/
Objective: To evaluate gene expression during treatment in dogs with IMHA compared to healthy dogs.
Animals: Client-owned dogs treated for IMHA using medical management (n=6), medical management and adjunct therapeutic plasma exchange (n=6), and healthy dogs (n=5).
Methods: Blood samples were collected on admission, day 5, and day 15 of treatment, or sooner if euthanized, for dogs with IMHA, and once for healthy dogs. RNA was isolated from peripheral blood mononuclear cells and gene expression evaluated using the nCounter® Canine IO Panel. Gene expression counts were normalized using the nf-core Nanostring pipeline. Differential expression analysis was completed using the nf-core differential abundance tool.
Results: At admission, differential gene analysis between patients with IMHA and healthy dogs revealed upregulation of 120 genes and downregulation of 46 genes associated with the immune response. Strongly upregulated genes included genes associated with the complement cascade (C3 L2FC 7.3; C9 L2FC 6.29), macrophage function (MARCO L2FC 8.9; CD209 L2FC 8.04), and neutrophil function (ELANE L2FC 6.8). On admission, no gene was found to be associated with survival on day 30 or with hemolysis type (intravascular versus extravascular). There was no significant change in gene expression following treatment.
Conclusions and Clinical Importance: Altered immune gene expression persisted two weeks after initiation of IMHA treatment in this cohort. Assessment over a longer time period may be needed to identify factors associated with treatment response.
