Inactivation of viruses by pasteurization at 60 °C for 10 h with and without 40% glucose as stabilizer during a new manufacturing process of α2-Macroglobulin from Cohn Fraction IV

Assessment on the efficacy of methods 2 to 5 and method 7 set out in Commission Regulation (EU) No 142/2011 to inactivate relevant pathogens when producing processed animal protein of porcine origin intended to feed poultry and aquaculture animals

An assessment was conducted on the level of inactivation of relevant pathogens that could be present in processed animal protein of porcine origin intended to feed poultry and aquaculture animals when methods 2 to 5 and method 7, as detailed in Regulation (EU) No 142/2011, are applied. Five approved scenarios were selected for method 7. Salmonella Senftenberg, Enterococcus faecalis, spores of Clostridium perfringens and parvoviruses were shortlisted as target indicators. Inactivation parameters for these indicators were extracted from extensive literature search and a recent EFSA scientific opinion. An adapted Bigelow model was fitted to retrieved data to estimate the probability that methods 2 to 5, in coincidental and consecutive modes, and the five scenarios of method 7 are able to achieve a 5 log10 and a 3 log10 reduction of bacterial indicators and parvoviruses, respectively. Spores of C. perfringens were the indicator with the lowest probability of achieving the target reduction by methods 2 to 5, in coincidental and consecutive mode, and by the five considered scenarios of method 7. An expert knowledge elicitation was conducted to estimate the certainty of achieving a 5 log10 reduction of spores of C. perfringens considering the results of the model and additional evidence. A 5 log10 reduction of C. perfringens spores was judged: 99-100% certain for methods 2 and 3 in coincidental mode; 98-100% certain for method 7 scenario 3; 80-99% certain for method 5 in coincidental mode; 66-100% certain for method 4 in coincidental mode and for method 7 scenarios 4 and 5; 25-75% certain for method 7 scenario 2; and 0-5% certain for method 7 scenario 1. Higher certainty is expected for methods 2 to 5 in consecutive mode compared to coincidental mode.

Improvement of irradiation-induced fibroblast damage by α2-macroglobulin through alleviating mitochondrial dysfunction

CONTEXT

α2-Macroglobulin (α2-M) is believed to be a potential anti-irradiation agent, but related mechanisms remains unclear.

OBJECTIVE

We investigated the irradiation protective effect of α2-M.

MATERIALS AND METHODS

A total of 10 Gy dose of irradiation was used to damage human skin fibroblasts. The influence of α2-M (100 µg/mL) on the proliferation, migration, invasion and apoptosis of fibroblasts was observed using Cell Counting Kit-8 (CCK8), wound healing, transwell, and flow cytometry. Malondialdehyde, superoxide dismutase and catalase was measured using related ELISA kits. The levels of mitochondrial membrane potential and calcium were detected using flow cytometry. The expression of transient receptor potential melastatin 2 (TRPM2) was investigated through western blotting and immunofluorescence staining.

RESULTS

High purity of α2-M was isolated from Cohn fraction IV. α2-M significantly increased cell proliferation, migration, invasion, but suppressed cell apoptosis after irradiation. The promotion of cell proliferation, migration and invasion by α2-M exceeded over 50% compared group irradiation. The increased cell ratio in the S phase and decreased cell ratio in the G2 phase induced by irradiation were remarkably reversed by α2-M. α2-M markedly suppressed the increased oxidative stress level caused by irradiation. The mitochondrial damage induced by irradiation was improved by α2-M through inhibiting mitochondrial membrane potential loss, calcium and TRPM2 expression.

DISCUSSION AND CONCLUSIONS

α2-M significantly promoted the decreased fibroblast viability and improved the mitochondria dysfunction caused by irradiation. α2-M might present anti-radiation effect through alleviating mitochondrial dysfunction caused by irradiation. This study could provide a novel understanding about the improvement of α2-M on irradiation-induced injury.

Inactivation and Removal of Chikungunya Virus and Mayaro Virus from Plasma-derived Medicinal Products

Background: Chikungunya virus (CHIKV) and Mayaro virus (MAYV) are closely related members of the Semliki Forest complex within the genus alphavirus and are transmitted by arthropods, causing acute febrile illness in humans. CHIKV has spread to almost all continents, whereas autochthonous MAYV infections have been reported in South America and in the Caribbean. Nevertheless, there was concern about potential spread of MAYV to other regions similar to CHIKV in the past. The risk for transmission of emerging viruses by blood transfusion and the safety of plasma-derived medicinal products (PDMPs) are constant concerns. The manufacturing processes of PDMPs include procedures to inactivate/remove viruses. Methods: In this study, we investigated the reduction of MAYV and CHIKV by heat inactivation in various matrices, solvent/detergent treatment and nanofiltration. Results: Unexpectedly, MAYV was significantly more resistant to heat and solvent/detergent treatment compared to CHIKV. However, being similar in size, both MAYV and CHIKV were removed below the detection limit by 35 nm virus filters. Conclusions: The inactivation profiles of different alphavirus members vary considerably, even within the Semliki Forest Complex. However, robust dedicated viral inactivation/removal procedures commonly used in the plasma product industry are effective in inactivating or removing MAYV and CHIKV.