CD33/SIGLEC3 Recombinant Proteins, Domain ECDs and Stable Cell Lines

CD33, also known as SIGLEC3, is a type I inhibitory Siglec expressed primarily on myeloid progenitors, monocytes, macrophages, and many malignant myeloid cells. Its extracellular region contains V-set and C2-set immunoglobulin-like domains that recognize sialylated glycans, while intracellular ITIM-related motifs recruit phosphatases and modulate myeloid-cell activation. CD33 expression is comparatively low on primitive hematopoietic stem cells but can be high on malignant myeloid populations, making it a well-established target for antibody-based research. CD33 also undergoes antibody-mediated internalization, an important property for ADC and other intracellular-delivery strategies.

DIMA BIOTECH provides full human CD33 ECD and domain-specific constructs, together with mouse CD33 protein, for ELISA, antibody screening, epitope mapping, domain-recognition studies, and cross-species evaluation. Flow cytometry-validated monoclonal antibodies, reference antibodies, and PE/biotin-conjugated formats support cell-surface detection and candidate benchmarking. A CD33-overexpressing 293T stable cell line provides a standardized platform for FACS, cell binding, internalization, and cellular candidate screening. The combination of domain-specific antigens and cell-based tools is especially useful for evaluating epitope-dependent internalization and antibody specificity.