Figure 5
![Figure 5. Hirudin inactivates thrombin and reduces the immunogenicity of FVIII. FVIII−/−/C57BL/6 mice received 5 intraperitoneal injections of 1 μg FVIII (n = 5) only or 1 μg FVIII with 200 μg hirudin (n = 5). This experiment was repeated twice, and representative results are reported here. Seven days after the last injection, (A) serum samples were analyzed for antibody response (515 ± 168 [FVIII] vs 134 ± 16 [FVIII + hirudin] μg/mL; *P = .02) and (B) splenic T cells were assayed for the response to FVIII (*P < .002). These data indicate that thrombin is necessary for initiation of the immune response to FVIII.](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/114/21/10.1182_blood-2008-10-186452/4/zh89990944920005.jpeg?Expires=1724276230&Signature=Xe74g~ry1EWH8OQG9T0CUZIWch7hwaH~THb-OqqVtno~1t1en6xIeAMzVEXi5CiGtFbLyRjYKmOxouLpH~YIDnMcspM9Eb4tpsh8Dey6HKIM3G67SkE7KUIgto8-DUciHtm1OA9vFJD3Yyd4lFBjCibZzu5s18ZOPgxG03v3pFLmSyJEDtNnbH9IP~V715IO9OAqkCyygCU5a2kmb3xxdtG~TSU10vthR3Wd0xQHwfuACpV9sF-uJfIgxutarwYNq1xPTnhzUGWj68Amlf8ySIexwtoTlQS58j7FsypgCBG~k~1pDATWL8riKUXZ8KnDi~F3nKaGWdn7ViznEuax6w__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Hirudin inactivates thrombin and reduces the immunogenicity of FVIII. FVIII−/−/C57BL/6 mice received 5 intraperitoneal injections of 1 μg FVIII (n = 5) only or 1 μg FVIII with 200 μg hirudin (n = 5). This experiment was repeated twice, and representative results are reported here. Seven days after the last injection, (A) serum samples were analyzed for antibody response (515 ± 168 [FVIII] vs 134 ± 16 [FVIII + hirudin] μg/mL; *P = .02) and (B) splenic T cells were assayed for the response to FVIII (*P < .002). These data indicate that thrombin is necessary for initiation of the immune response to FVIII.
