Abstract: Objective To investigate the activation of the complement system in the retina in a mouse model of
endotoxin-induced uveitis (EIU). Methods Balb/c mice were randomly divided into control group and lipopolysaccharide
(LPS)-induced EIU group. Twenty-four hours after modeling, the expressions of the major complement components of the
classical pathway (CP), mannose-binding lectin (MBL) pathway, alternative pathway (AP), and terminal pathway in the retina
were determined by quantitative RT-PCR. Western blotting was employed to examine the protein expressions of the key
components of the complement system involved in the CP and AP pathways in the retina. Results Normal mouse retina
expressed a variety of complement components that were involved mainly in the CP and AP pathways. The expressions of the
complement components involved in the CP and AP pathways were up-regulated in the retina of mice with EIU. Although
MASP1 and MASP2 were detected in the retina in both the EIU and control groups, their expressions were weak and showed
no significant difference between the two groups. Conclusion The AP and CP but not the MBL pathways of the complement
system are activated in the retina of mice with EIU, suggesting a role of the activated complement system in the pathological
process of EIU.