Transforming growth factor beta concentrations and interferon gamma responses in cerebrospinal fluid of horses with equine protozoal myeloencephalitis.
Authors: Furr M, Pontzer C
Journal: Equine veterinary journal
Summary
# Editorial Summary Equine protozoal myeloencephalitis (EPM) involves complex immune dysregulation within the central nervous system, yet the specific immunomodulatory mechanisms remain incompletely understood. Furr and Pontzer investigated whether cerebrospinal fluid (CSF) concentrations of transforming growth factor beta-2 (TGF-β2)—a key anti-inflammatory cytokine—differ between healthy horses and those with EPM, and whether CSF itself influences interferon-gamma responses in immune cells. Using validated immunoassays on samples from nine affected and nine control horses, alongside in vitro bioassays with peripheral blood mononuclear cells, they found that CSF TGF-β2 concentrations were significantly lower in EPM-affected horses (144 pg/ml versus 256 pg/ml; P = 0.03), suggesting impaired local anti-inflammatory signalling. Whilst both normal and EPM CSF enhanced interferon-gamma production when stimulated in vitro, blocking TGF-β2 with monoclonal antibodies produced divergent trends—slightly increasing responses to normal CSF and slightly decreasing responses to EPM CSF—indicating that TGF-β2 contributes to CSF's immunomodulatory capacity. For practitioners, these findings suggest that altered cytokine balance within the CNS may perpetuate neuroinflammation in EPM cases, potentially informing future therapeutic approaches targeting immune tolerance and opening avenues for biomarker-based prognostic assessment of disease severity and treatment response.
Read the full abstract on PubMed
Practical Takeaways
- •EPM appears to involve altered immune regulation in the central nervous system, with reduced TGF-beta2 levels potentially contributing to disease pathophysiology
- •Understanding CSF immunomodulatory properties may lead to improved diagnostic and therapeutic approaches for EPM management
- •This research supports investigating immune-based mechanisms in EPM rather than relying solely on antiprotozoal treatments
Key Findings
- •TGF-beta2 concentration in cerebrospinal fluid was significantly lower in EPM-affected horses (144 pg/ml) compared to normal horses (256 pg/ml, P = 0.03)
- •Cerebrospinal fluid from both normal and EPM-affected horses enhanced interferon-gamma production by stimulated peripheral blood mononuclear cells
- •Anti-TGF-beta2 monoclonal antibodies produced minimal effects on interferon-gamma response that did not reach statistical significance
- •Results suggest TGF-beta2 production is altered in EPM and cerebrospinal fluid contains immunomodulatory substances