Sheep IgG (Fab) [HRP]

Real-time monitoring of product titers during process development and production of biotherapeutics facilitate implementation of quality-by-design principles and enable rapid bioprocess decision and optimization of the production process. Conventional analytical methods are generally performed offline/at-line and, therefore, are not capable of generating real-time data. In this study, a novel fiber optical nanoplasmonic sensor technology was explored for rapid IgG titer measurements. The sensor combines localized surface plasmon resonance transduction and robust single use Protein A-modified sensor chips, housed in a flexible flow cell, for specific IgG detection. The sensor requires small sample volumes (1-150 mu L) and shows a reproducibility and sensitivity comparable to Protein G high performance liquid chromatography-ultraviolet (HPLC-UV). The dynamic range of the sensor system can be tuned by varying the sample volume, which enables quantification of IgG samples ranging from 0.0015 to 10 mg/mL, without need for sample dilution. The sensor shows limited interference from the sample matrix and negligible unspecific protein binding. IgG titers can be rapidly determined in samples from filtered unpurified Chinese hamster ovary (CHO) cell cultures and show good correlation with enzyme-linked immunosorbent assay (ELISA).

Background/Aim: Cytomegalovirus (CMV) replication may cause life-threatening complications after allogeneic haematopoietic stem cell transplantation (allo-HSCT). The aim of the study was to characterize CMV events, and the outcome of letermovir (LTV) CMV prophylaxis. Patients and Methods: In this retrospective analysis of patients treated with an allo-HSCT between 2010 and 2020, we determined plasma CMV events, as well as associated risk factors. Results: We identified 423 patients who had undergone allo-HSCT between 2010 and 2020. CMV DNAemia was found in 130/423 (30.7%) of patients. CMV reactivation rate was significantly higher in patients with acute graft-versus-host disease, HLA mismatch, and CMV IgG seropositivity of donors and recipients. Among 42 patients receiving LTV prophylaxis those, 5 (11.9%) showed CMV DNAemia under LTV versus 87/353 (24.6%) in a control group. Conclusion: Despite the development of better approaches with weekly monitoring and early treatment initiation, CMV reactivations play an important role after allo-HSCT.