A Benchmark Fed-Batch Bioprocess for Production of cNISTmAb using NISTCHO

The end-to-end characterization of a fed-batch bioprocess for expressing a non-originator version of the NISTmAb IgG1 (cNISTmAb) using NISTCHO, a high-performance CHO production cell line available as a NIST reference material (RM 8675), is described. NISTCHO was developed to support bioprocess reproducibility, cross-laboratory standardization, technology benchmarking, and collaborative innovation in biomanufacturing process research. Propagation, scale-up, and cultivation of NISTCHO in fed-batch mode using 3 L single-use bioreactors is shown to yield reproducible titers exceeding 2 g/L. Upstream cell culture performance demonstrated predictable growth kinetics, sustained viability, and stable cell morphology across independent bioreactor runs. Metabolite analysis revealed characteristic CHO behavior, including lactate accumulation followed by consumption during later culture stages. Downstream purification consisting of Protein A (proA) capture followed by sequential anion exchange and cation exchange chromatography enabled efficient removal of host cell proteins and nucleic acids, producing high-purity antibody with overall recoveries of (62 to 70) %. Fc glycosylation analysis demonstrated a profile dominated by core fucosylated and galactosylated species, with low levels of high-mannose and α2,6-sialylated glycans, consistent with a typical CHO-derived IgG1 product. Together, these results establish a reproducible upstream and downstream bioprocess for high-yield, high-purity cNISTmAb using NISTCHO.