Distribution of cytokine proteins within epiretinal membranes in proliferative vitreoretinopathy.

This study reports on the immunohistochemical staining for cytokine proteins of 26 epiretinal membranes obtained from eyes undergoing surgery for the treatment of proliferative vitreoretinopathy. All specimens were investigated for the distribution of staining for interleukin-lα (IL-lα), interleukin-1β (IL-1β), inter-leukin-6 (IL-6), tumour necrosis factor-α (TNFα), interferon-γ (IFNγ) and interleukin-2 (IL-2). The results showed that 22 of the membranes (85%) stained for TNFα not only intracellularly but also in the extracellular matrix. This contrasts with the findings that only 2 membranes stained for IL-lα and that another 3 were positive for IL-1β. Staining for the cytokines IL-6 and IFNγ was also observed in 9 and 7 membranes respectively. None of the specimens investigated stained with antibodies to IL-2 or control antibodies, and none of three normal retinas stained with any of the antibodies used. Pre-absorption of anti-cytokine antibodies with the corresponding human recombinant cytokines abolis...