Affinity purification of recombinant human plasminogen activator from transgenic rabbit milk using a novel polyolresponsive monoclonal antibody

Purpose: To develop processes for effective isolation and purification of recombinant human plasminogen activator (rhPA) from transgenic rabbit milk. Methods: Immunoaffinity chromatography was selected and improved by a special polyol-responsive monoclonal antibody (PR-mAb). Alteplase was used as immunogen because of its similarity to rhPA in terms of structure. The PR-mAb was prepared by hybridoma technology and screened by ELISA-elution assay. Screening antibody was performed using rhPA milk in an ELISA-elution assay. The antibody clone C4-PR-mAb was selected for immunoaffinity chromatography. The rhPA was effectively bound to immobilized C4-PR-mAb on the column and was eluted with Tris buffer comprising 0.75 mol/L ammonium sulfate and 40n% propanediol (pH7.9). The rhPA was further purified by passing through Chromdex75 gel filtration column. Results: There were 12 hybridoma strains selected into the polyol-responsive mAbs screen step and three hybridoma strains were superior for producing PR-mAbs (C1, C4, C8). The rhPA can be purified from transgenic rabbit milk and maintained a higher thrombolytic activity in vitro by FAPA. Conclusion: The results demonstrate the suitability of the alternative approach used in this study. Using immunoaffinity chromatography and gel filtration column is feasible and convenient for extracting rhPA from milk, and should be useful for purifying other tPA mutants or other novel recombinant milkderived proteins.

Clinical efficacy and safety of edaravone therapy in acute cerebral haemorrhage

Purpose: To evaluate the clinical efficacy and safety of edaravone in the treatment of acute cerebral haemorrhage (ACH). Methods: This study recruited 120 patients who developed ACH. The patients were divided into control and treatment groups with 60 patients per group. The control group underwent conventional treatment and the treatment group also received intravenous edaravone. The volumes of cerebral edema and cerebral hematoma, high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) levels, and Chinese Stroke Scale (CSS) score before and after treatment were compared between the two groups. Results: The respective cerebral edema volumes of the control and treatment groups decreased from 20.99 ± 12.09 and 21.80 ± 12.01 mL on day 0 to 11.23 ± 6.34 and 12.11 ± 5.98 mL at day 7 and 4.69 ± 4.03 and 4.64 ± 3.9 mL on day 14 (P < 0.05). The respective cerebral hematoma volumes of the control and treatment groups decreased from 18.98 ± 12.04 and 18.97 ± 12.07 mL on day 0 to 12.34 ± 6.57 and 11.89 ± 4.01 mL at day 7 and 9.49 ± 3.95 and 9.52 ± 3.96 mL on day 14. Compared with pretreatment, hs-CRP and IL-6 levels and CSS score of the two groups decreased significantly following treatment (p < 0.05); the differences in the cerebral edema and hematoma volumes of the two groups on days 7 and 14 were not significant (p > 0.05). The hs-CRP and IL-6 levels and CSS scores of the treatment group decreased appreciably (p < 0.05), while the incidence of adverse reactions in the treatment and control groups was 16.67 and 13.33 %, respectively, but the difference was not significant (p > 0.05). Conclusion: Edaravone shows remarkable clinical efficacy and safety with no obvious adverse reactions in the treatment of ACH. Therefore, its use is recommended.