ABSTRACT
BACKGROUND: Antivenoms are the only validated treatment against snakebite envenoming. Numerous drawbacks pertaining to their availability, safety and efficacy are becoming increasingly evident due to low sustainability of current productions. Technological innovation of procedures generating therapeutics of higher purity and better physicochemical characteristics at acceptable cost is necessary. The objective was to develop at laboratory scale a compact, feasible and economically viable platform for preparation of equine F(ab')2 antivenom against Vipera ammodytes ammodytes venom and to support it with efficiency data, to enable estimation of the process cost-effectiveness. METHODS: The principle of simultaneous caprylic acid precipitation and pepsin digestion has been implemented into plasma downstream processing. Balance between incomplete IgG breakdown, F(ab')2 over-digestion and loss of the active drug's protective efficacy was achieved by adjusting pepsin to a 1:30 substrate ratio (w/w) and setting pH at 3.2. Precipitation and digestion co-performance required 2 h-long incubation at 21 °C. Final polishing was accomplished by a combination of diafiltration and flow-through chromatography. In vivo neutralization potency of the F(ab')2 product against the venom's lethal toxicity was determined. RESULTS: Only three consecutive steps, performed under finely tuned conditions, were sufficient for preservation of the highest process recovery with the overall yield of 74%, comparing favorably to others. At the same time, regulatory requirements were met. Final product was aggregate- and pepsin-free. Its composition profile was analyzed by mass spectrometry as a quality control check. Impurities, present in minor traces, were identified mostly as IgG/IgM fragments, contributing to active drug. Specific activity of the F(ab')2 preparation with respect to the plasma was increased 3.9-fold. CONCLUSION: A highly streamlined mode for production of equine F(ab')2 antivenom was engineered. In addition to preservation of the highest process yield and fulfillment of the regulatory demands, performance simplicity and rapidity in the laboratory setting were demonstrated. Suitability for large-scale manufacturing appears promising.
ABSTRACT
Antivenoms are the only validated treatment against snakebite envenoming. Numerous drawbacks pertaining to their availability, safety and efficacy are becoming increasingly evident due to low sustainability of current productions. Technological innovation of procedures generating therapeutics of higher purity and better physicochemical characteristics at acceptable cost is necessary. The objective was to develop at laboratory scale a compact, feasible and economically viable platform for preparation of equine F(ab')2 antivenom against Vipera ammodytes ammodytes venom and to support it with efficiency data, to enable estimation of the process cost-effectiveness. Methods: The principle of simultaneous caprylic acid precipitation and pepsin digestion has been implemented into plasma downstream processing. Balance between incomplete IgG breakdown, F(ab')2 over-digestion and loss of the active drug's protective efficacy was achieved by adjusting pepsin to a 1:30 substrate ratio (w/w) and setting pH at 3.2. Precipitation and digestion co-performance required 2 h-long incubation at 21 °C. Final polishing was accomplished by a combination of diafiltration and flow-through chromatography. In vivo neutralization potency of the F(ab')2 product against the venom's lethal toxicity was determined. Results: Only three consecutive steps, performed under finely tuned conditions, were sufficient for preservation of the highest process recovery with the overall yield of 74%, comparing favorably to others. At the same time, regulatory requirements were met. Final product was aggregate- and pepsin-free. Its composition profile was analyzed by mass spectrometry as a quality control check. Impurities, present in minor traces, were identified mostly as IgG/IgM fragments, contributing to active drug. Specific activity of the F(ab')2 preparation with respect to the plasma was increased 3.9-fold. Conclusion: A highly streamlined mode for production of equine F(ab')2 antivenom was engineered. In addition to preservation of the highest process yield and fulfillment of the regulatory demands, performance simplicity and rapidity in the laboratory setting were demonstrated. Suitability for large-scale manufacturing appears promising.(AU)
Subject(s)
Antivenins , Downstream , Immunotherapy , Chromatography, Ion Exchange , Mass SpectrometryABSTRACT
Antivenoms are the only validated treatment against snakebite envenoming. Numerous drawbacks pertaining to their availability, safety and efficacy are becoming increasingly evident due to low sustainability of current productions. Technological innovation of procedures generating therapeutics of higher purity and better physicochemical characteristics at acceptable cost is necessary. The objective was to develop at laboratory scale a compact, feasible and economically viable platform for preparation of equine F(ab')2 antivenom against Vipera ammodytes ammodytes venom and to support it with efficiency data, to enable estimation of the process cost-effectiveness. Methods: The principle of simultaneous caprylic acid precipitation and pepsin digestion has been implemented into plasma downstream processing. Balance between incomplete IgG breakdown, F(ab')2 over-digestion and loss of the active drug's protective efficacy was achieved by adjusting pepsin to a 1:30 substrate ratio (w/w) and setting pH at 3.2. Precipitation and digestion co-performance required 2 h-long incubation at 21 °C. Final polishing was accomplished by a combination of diafiltration and flow-through chromatography. In vivo neutralization potency of the F(ab')2 product against the venom's lethal toxicity was determined. Results: Only three consecutive steps, performed under finely tuned conditions, were sufficient for preservation of the highest process recovery with the overall yield of 74%, comparing favorably to others. At the same time, regulatory requirements were met. Final product was aggregate- and pepsin-free. Its composition profile was analyzed by mass spectrometry as a quality control check. Impurities, present in minor traces, were identified mostly as IgG/IgM fragments, contributing to active drug. Specific activity of the F(ab')2 preparation with respect to the plasma was increased 3.9-fold. Conclusion: A highly streamlined mode for production of equine F(ab')2 antivenom was engineered. In addition to preservation of the highest process yield and fulfillment of the regulatory demands, performance simplicity and rapidity in the laboratory setting were demonstrated. Suitability for large-scale manufacturing appears promising.(AU)
Subject(s)
Mass Spectrometry , Antivenins , Chromatography , Downstream , Plasma , ImmunotherapyABSTRACT
RATIONALE: Although the fruiting-body of the fungi of the genus Xylaria shows a great variety of morphological characteristics, their mycelial forms are always very similar, imposing difficulties for their identification. Intact cell mass spectrometry (ICMS) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) can be a fast and reliable strategy to support the differentiation/identification of Xylaria species in those cases where fruit-bodies are not available. METHODS: Many experimental parameters such as sample preparation and culture media are crucial for filamentous fungi analysis by MALDI-TOFMS. For the purposes of this study, we used four matrices (CHCA, DHB, FA and SA) with five different concentrations (0.1, 0.3, 0.5, 1.0 and 2.5%) of TFA in the matrix, the influence of six different culture media (solid and liquid), and three mycelium peptide/protein extraction protocols (acid, basic and thymol-supported solution) to optimize the sample preparation of the endophytic fungus X. arbuscula. RESULTS: It was observed that sinapinic acid (30 mg/mL) dissolved in acetonitrile/0.1% TFA and PDA were the best matrix solution and culture medium, respectively, for the ICMS of X. arbuscula. The formic acid and ammonium bicarbonate (AB) protocols provided similar mass spectra; however, a higher number of peaks were observed using AB extraction. Mass spectra obtained from different thymol-containing solutions (EtOH/aqueous 0.1% TFA and ACN/aqueous 0.1% TFA) show increasing peak abundances at m/z 3000-6500. CONCLUSIONS: X. arbuscula could be analyzed by ICMS. However, an extraction step was required to provide suitable MALDI mass spectra. Formic acid-, AB- and thymol-containing solutions were demonstrated to be good cocktails for the extraction of peptide/protein biomarkers from these fungi.