RESUMEN
There is a continuous need to improve the viral safety of plasma products, and we here report the development and optimization of a manufacturing-scale virus removal nanofiltration step for intravenous immunoglobulin (IVIG) using the recently introduced Planova™ BioEX filter. IVIG throughput was examined for various operating parameters: transmembrane pressure, temperature, protein concentration, and prefiltration methods. The developed procedure was based on filtering undiluted process solution (50.0â¯g/l IVIG) under constant transmembrane pressure filtration at 294â¯kPa and 25⯰C following prefiltration with a 0.1⯵m MILLEX VV filter. The recovery of IgG was approximately 98%, and no substantial changes in biochemical characteristics were observed before and after nanofiltration in scaled-up production. A viral clearance validation study with parvovirus under worst-case conditions performed at the National Institutes for Food and Drug Control of China (NIFDC) showed PPV logarithmic reduction value (LRV)â¯>â¯4. Improved viral safety of IVIG can be assured by implementing a Planova BioEX nanofiltration step to ensure effective parvovirus clearance under conditions providing excellent protein recovery and no detectable impact on product biochemical properties. This plasma-derived IVIG product is the first to be certified for parvovirus safety by the NIFDC in China.
Asunto(s)
Inmunoglobulinas Intravenosas/química , Inmunoglobulinas Intravenosas/aislamiento & purificación , Filtros Microporos , Humanos , Parvovirus , Presión , Ultrafiltración/instrumentación , Ultrafiltración/métodos , Inactivación de VirusRESUMEN
Alzheimer's disease (AD) is characterized by memory loss, intracellular neurofibrillary tangles, and extracellular plaque deposits composed of ß-amyloid (Aß). Previous reports showed that naturally occurring autoantibodies, such as intravenous immunoglobulin (IVIG), benefited patients with moderate-stage AD who carried an APOE-ε4 allele. However, the mechanism underlying the role of IVIG remains unclear. In this study, we identified naturally occurring autoantibodies against Aß oligomers (NAbs-Aßo), which were purified by Aß42 oligomer or Cibacron Blue affinity chromatography from IVIG and termed as Oli-NAbs and Blue-NAbs, respectively. Oli-NAbs and Blue-NAbs recognized Aß42 oligomers or both Aß40 and 42 oligomers, differently. Both antibodies inhibited Aß42 aggregation and attenuated Aß42-induced cytotoxicity. Compared with vehicles, Oli-NAbs, Blue-NAbs and IVIG significantly improved the memory and cognition, and reduced the soluble and oligomeric Aß levels in APPswe/PS1dE9 transgenic mice. Further investigation showed that Blue-NAbs at increased doses effectively decreased plaque burden and insoluble Aß levels, whereas Oli-NAbs significantly declined the microgliosis and astrogliosis, as well as the production of proinflammatory cytokines in vivo. Therefore, high levels of these antibodies against oligomeric Aß40 or Aß42 were required, correspondingly, to achieve the optimal effect. NAbs-Aßo could be condensed to a high concentration by affinity chromatography and its isolation from IVIG may not interfere with the normal function of conventional IVIG as its concentration is very low. Thus, the isolated NAbs-Aßo as an extra product of plasma required low cost and the enriched NAbs-Aßo may be more feasible than IVIG for the treatment of AD.