HEK293に発現する完全長CD20タンパク質

CD20はB細胞表面抗原として、プレB細胞と成熟したB細胞に発現しますが、前駆B細胞や成熟した形質細胞には発現しません。 また、CD20はB細胞由来のリンパ腫や白血病などの腫瘍細胞や炎症や免疫関連疾患に関与するB細胞に発現しているため、リンパ腫や白血病などの自己免疫疾患の治療標的にもなっています。

CD20分子を標的とした抗体医薬品は三つの世代開発されています。第一世代のヒト-マウスキメラ抗体のRitux*mabは代表的で、ヒト化が不十分なため、一部の患者には薬剤耐性や副作用が出ていました。第二世代ではヒト化修飾抗体のOfatumumabは代表的で、免疫原性を減少させ、副作用を抑制できましたが、抗体の特異性や抗原との親和性が低下します。第三世代はFcフラグメントグリコシル化修飾抗体でObinutuzumabが代表的で、抗体の特異性、抗原との結合親和性が高くなっているため、ADCCとADCP効果が増強されました。

モノクローナル抗体薬に限らず、CD20はCD3などの標的と結合することによって、二重特異性抗体を開発し、T細胞をB細胞の周囲に集めさせ、T細胞のB細胞に対する殺傷能力を促進します。

2e5 of CD20-CAR-293 cells transfected with anti-CD20-scFv were stained with 100 μL of 3 μg/mL of Biotinylated Human CD20 Full Length, His,Avitag (Cat. No. CD0-H82E3) and negative control protein respectively, washed and then followed by PE-SA and analyzed with FACS (QC tested).

2e5 of CD20-CAR-293 cells transfected with anti-CD20-scFv were stained with 100 μL of 3 μg/mL of Human CD20 / MS4A1 Full Length Protein, His Tag (Nanodisc) (HEK293)(Cat. No. CD0-H52H1) and negative control protein respectively, washed and then followed by PE anti-His antibody and analyzed with FACS (QC tested).

Immobilized RTX at 5 μg/mL (100 μL/well) can bind Biotinylated Human CD20 Full Length, His,Avitag (Cat. No. CD0-H82E3) with a linear range of 0.008-0.125 μg/mL

Immobilized RTX at 2 μg/mL (100 μL/well) can bind Human CD20 Full Length, His Tag (Cat. No. CD0-H52H1) with a linear range of 1-63 ng/mL

Immobilized RTX at 2 μg/mL (100 μL/well) can bind Biotinylated Human CD20 Full Length, His,Avitag (HEK293) (Cat. No. CD0-H82E5) with a linear range of 4-63 ng/mL (in presence of DDM and CHS).

Immobilized anti-CD20 antibody at 2 μg/mL (100 μL/well) can bind Biotinylated Human CD20 Full Length, His,Avitag (HEK293) (Cat. No. CD0-H82E5) with a linear range of 4-63 ng/mL (in presence of DDM and CHS).

Immobilized RTX at 2 μg/mL (100 μL/well) can bind Human CD20 Full Length, His Tag, HEK293 (SPR verified) (Cat. No. CD0-H52H3) with a linear range of 0.4-3 ng/mL (in presence of DDM and CHS).

Immobilized anti-CD20 antibody at 2 μg/mL (100 μL/well) can bind Human CD20 Full Length, His Tag, HEK293 (SPR verified) (Cat. No. CD0-H52H3) with a linear range of 0.4-6 ng/mL (in presence of DDM and CHS).

Biotinylated Human CD20, His,Avitag (HEK293) (Cat. No. CD0-H82E5) captured on Biotin CAP-Series S Sensor Chip can bind RTX with an affinity constant of 1.73 nM as determined in a SPR assay (in presence of DDM and CHS) (Biacore T200).

Human CD20 Full Length, His Tag, HEK293 (SPR verified) (Cat. No. CD0-H52H3) captured on CM5 chip via Anti-human IgG Fc antibodies surface can bind RTX with an affinity constant of 6.21 nM as determined in a SPR assay (in presence of DDM and CHS) (Biacore 8K).