Anti-CD19 Antibody (FMC63) is an antibody that binds to CD19, with a human K d value ranging from 0.42 nM to 149 nM. Anti-CD19 Antibody (FMC63) mediates tumor cell killing, cytokine secretion, stable CAR expression, T cell activation and memory differentiation. Anti-CD19 Antibody (FMC63) fails to eliminate lymphoma cells carrying CD19 point mutations or co-expressing FMC63-CAR19, induces higher levels of activation-induced cell death, and reduces cell persistence. Anti-CD19 Antibody (FMC63) can be used in research related to B-cell non-Hodgkin's lymphoma, B-cell acute lymphoblastic leukemia, relapsed or refractory diffuse large B-cell lymphoma, etc [1] [2] [3] [4].
In Vitro, Anti-CD19 Antibody (FMC63) (10 μg/mL; 10 min) recognizes a CD19 epitope distinct from that recognized by h1218, as shown by simultaneous binding of h1218 to FMC63-bound CD19 in an Octet epitope binning assay[1]. Anti-CD19 Antibody (FMC63) (50-1600 nM) binds to recombinant human CD19-ECD-Ck with a mean Kd of 149 nM, a slow on-rate of 8.94 × 103 (1/Ms), and a slow off-rate of 1.31 × 10-3 (1/s) in an Octet affinity measurement assay[1]. Anti-CD19 Antibody (FMC63) relies on the membrane-distal amino acid H218 in CD19 for binding, as shown by reduced binding to HEK293T cells expressing the CD19H218/KSS mutant in a flow cytometry-based epitope mapping assay[1]. Soluble FvFc fusion protein of Anti-CD19 Antibody (FMC63) (37.5, 18.75, 9.375, 4.688, 2.344, 1.17 nM; 160 sec association, 300 sec dissociation) binds to recombinant extracellular CD19 with a KD of 0.42 nM[3]. Soluble FvFc fusion protein of Anti-CD19 Antibody (FMC63) (5-50 nM; 30 min) specifically binds to CD19+ Raji cells, with 95.6% binding at 5 nM and 98.9% binding at 50 nM[3].
References:
[1]. Zhang Y, et al. Safety and efficacy of a novel anti-CD19 chimeric antigen receptor T cell product targeting a membrane-proximal domain of CD19 with fast on- and off-rates against non-Hodgkin lymphoma: a first-in-human study. Molecular cancer. 2023 Dec 09;22(1):200.
[2]. Seigner J, et al. Solving the mystery of the FMC63-CD19 affinity. Scientific reports. 2023 Dec 27;13(1):23024.
[3]. Andrade CO, et al. Development and evaluation of novel humanized CD19 CAR-T cells for advanced B cell malignancies. Frontiers in immunology. 2026;17:1798748.
[4]. Seipel K, et al. Clinical Impact of Single Nucleotide Polymorphism in CD-19 on Treatment Outcome in FMC63-CAR-T Cell Therapy. Cancers. 2023 Jun 05;15(11):3058.
In Vitro, Anti-CD19 Antibody (FMC63) (10 μg/mL; 10 min) recognizes a CD19 epitope distinct from that recognized by h1218, as shown by simultaneous binding of h1218 to FMC63-bound CD19 in an Octet epitope binning assay[1]. Anti-CD19 Antibody (FMC63) (50-1600 nM) binds to recombinant human CD19-ECD-Ck with a mean Kd of 149 nM, a slow on-rate of 8.94 × 103 (1/Ms), and a slow off-rate of 1.31 × 10-3 (1/s) in an Octet affinity measurement assay[1]. Anti-CD19 Antibody (FMC63) relies on the membrane-distal amino acid H218 in CD19 for binding, as shown by reduced binding to HEK293T cells expressing the CD19H218/KSS mutant in a flow cytometry-based epitope mapping assay[1]. Soluble FvFc fusion protein of Anti-CD19 Antibody (FMC63) (37.5, 18.75, 9.375, 4.688, 2.344, 1.17 nM; 160 sec association, 300 sec dissociation) binds to recombinant extracellular CD19 with a KD of 0.42 nM[3]. Soluble FvFc fusion protein of Anti-CD19 Antibody (FMC63) (5-50 nM; 30 min) specifically binds to CD19+ Raji cells, with 95.6% binding at 5 nM and 98.9% binding at 50 nM[3].
References:
[1]. Zhang Y, et al. Safety and efficacy of a novel anti-CD19 chimeric antigen receptor T cell product targeting a membrane-proximal domain of CD19 with fast on- and off-rates against non-Hodgkin lymphoma: a first-in-human study. Molecular cancer. 2023 Dec 09;22(1):200.
[2]. Seigner J, et al. Solving the mystery of the FMC63-CD19 affinity. Scientific reports. 2023 Dec 27;13(1):23024.
[3]. Andrade CO, et al. Development and evaluation of novel humanized CD19 CAR-T cells for advanced B cell malignancies. Frontiers in immunology. 2026;17:1798748.
[4]. Seipel K, et al. Clinical Impact of Single Nucleotide Polymorphism in CD-19 on Treatment Outcome in FMC63-CAR-T Cell Therapy. Cancers. 2023 Jun 05;15(11):3058.