Histological changes induced by the new 4-clone cocktail (CII-3, CII-6, C2B-14, and C2A-12). DBA/1J mice were injected with the new 4-clone cocktail on day 0 followed by LPS. On day 10, the front paws were amputated for histological examination. The tissues were stained with H&E and for immunohistochemistry (TNF-alpha and IL-1beta). Results shown are representative histological pictures of five mice ankle joints in each group. A: normal paw, B: arthritis, C: normal ankle joint, D: arthritic ankle joint, E: normal TNF- alpha, F: arthritic TNF- alpha, G: normal IL-1 beta, H: arthritic IL-1 beta.