title: Development and clinical application of immunoassays for European adder (Vipera berus berus) venom and antivenom.
abstract: An ovine affinity purified Fab antivenom was used in a clinical trial in Sweden to treat European adder (Vipera berus berus) envenoming. Immunoassays were developed to measure V. b. berus venom and antivenom concentrations in clinical samples to help assess the efficacy of treatment. A radioimmunoassay (RIA) was developed, optimized and validated to measure plasma levels of V. b. berus venom and compared with a conventional ELISA. Both showed a similar variation of zero binding in biological samples and the results obtained correlated closely. However, the ELISA was quicker and more sensitive (0.8 compared with 2 micrograms/litre). Before administration of antivenom, V. b. berus venom concentrations in plasma ranged from 10 to 53 micrograms/litre; 12 hr after the Fab infusion, no patient had measurable levels. However, two patients had low venom levels 24 hr after treatment. ELISA and RIA were also developed, optimized and used to measure concentrations of free Fab in plasma. There was a biexponential fall of Fab concentration with a fast distribution phase (t 1/2 = 0.9 hr) and a slower elimination phase (t 1/2 = 18 hr). The amount of Fab excreted in urine was low.
authors.affiliation: Therapeutic Antibodies Ltd, Medical College of St Bartholomew's Hospital, London.
authors.forename: L
authors.initials: L
authors.lastname: Sjostrom
authors.forename: C
authors.initials: C
authors.lastname: Karlson-Stiber
authors.forename: H
authors.initials: H
authors.lastname: Persson
authors.forename: I H
authors.initials: IH
authors.lastname: Al-Abdulla
authors.forename: D C
authors.initials: DC
authors.lastname: Smith
mesh_terms: D000818:Animals; D000997:Antivenins / Q000008:administration & dosage / Q000627:therapeutic use* / Q000652:urine; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D007140:Immunoglobulin Fab Fragments / Q000008:administration & dosage / Q000627:therapeutic use* / Q000652:urine; D007262:Infusions, Intravenous; D008297:Male; D011863:Radioimmunoassay; D012909:Snake Bites / Q000188:drug therapy*; D012911:Snakes; D013548:Sweden; D014757:Viper Venoms / Q000009:adverse effects / Q000032:analysis* / Q000378:metabolism
chemical_list: D000997:Antivenins; D007140:Immunoglobulin Fab Fragments; D014757:Viper Venoms