ABCB8 Antibody

Definition and Biological Context

ABCB8 (ATP-binding cassette subfamily B member 8) is a mitochondrial inner membrane protein critical for cellular iron homeostasis, energy metabolism, and drug efflux. The ABCB8 antibody is a polyclonal reagent primarily used to detect and study this transporter in research settings. It is generated in rabbits using immunogens derived from human ABCB8 sequences, such as amino acids 469–718 .

Target Epitope and Reactivity

• Immunogen: Recombinant peptides corresponding to specific regions of ABCB8 (e.g., residues 469–718 in humans) .

• Reactivity: Human, mouse, and rat samples .

• Molecular Weight: ~80 kDa .

Mechanistic Insights

ABCB8 functions as an ATP-dependent transporter regulating mitochondrial iron export and ATP-sensitive potassium (mitoK$_{ATP}$) channels . It also mediates doxorubicin (DOX) efflux, influencing drug resistance in cancers and cardiotoxicity .

Role in Drug Resistance and Toxicity

• Cancer: ABCB8 overexpression in tumors enhances DOX efflux, contributing to chemoresistance .

• Cardiotoxicity: Downregulation of ABCB8 in cardiomyocytes increases DOX retention and oxidative stress, exacerbating cardiac damage .

Iron Regulation

ABCB8 expression is inversely correlated with cellular iron levels:

• Iron overload reduces ABCB8, impairing DOX efflux .

• Iron chelation upregulates ABCB8, mitigating toxicity .

Applications in Research

• Mitochondrial Studies: Localizes ABCB8 to the inner mitochondrial membrane .

• Disease Models:

  • Hereditary hemochromatosis (HH): ABCB8 deficiency exacerbates DOX cardiotoxicity .

  • Cancer: ABCB8 inhibition reverses chemoresistance in breast and renal cancers .

• Techniques:

  • Western Blot: Detects ABCB8 in lysates from heart, liver, and cancer cell lines (e.g., MCF7, Jurkat) .

  • IHC: Identifies ABCB8 in formalin-fixed tissues (e.g., human testis, mouse heart) .

Validation Data

• Western Blot: Bands at ~80 kDa in human fetal heart, HepG2, and Jurkat lysates .

• Immunofluorescence: Mitochondrial localization in HeLa cells .