Animal Models in Rheumatoid Arthritis: Is There a Correlation Between Autoantibodies in Human Pathology and Animal Models?

RA is a chronic autoimmune disease characterized by synovial inflammation and joint damage, driven by autoantibodies such as ACPA, anti-CarP and RF. These autoantibodies, influenced by genetic and environmental factors, play a crucial role in RA pathogenesis through post-translational modifications like citrullination, carbamylation, and acetylation. The early detection of ACPA provides a potential window for intervention, while anti-CarP antibodies correlate with severe disease progression and RF aids in diagnosis. Translating these findings from human pathology to animal models presents significant challenges. Although the presence of adaptative immune cells (T cells) is well defined in animal models of RA, studies yield inconsistent results regarding autoantibody production and implication in the disease onset and progression, with varying detectability of ACPA, anti-CarP antibodies, and RF across different species and models. The collagen-induced arthritis (CIA) model shows PAD4 expression and citrullinated protein presence but inconsistent ACPA detection, while the K/BxN model elucidates the pathogenicity of anti-GPI autoantibodies and implicates Fcγ receptors in disease processes. Therefore, further research is needed to bridge the gap between animal models and human RA pathology. Future studies should focus on developing more representative animal models, exploring pharmacological targets and pathways that involve the interplay between anti-inflammatory and autoimmune responses, and investigating the complex interplay between genetic predisposition, environmental triggers, and autoimmune mechanisms. This approach may lead to improved early diagnostic tools, targeted therapies, and potentially preventive strategies for RA, ultimately enhancing patient outcomes and quality of life.