RABA5A Antibody

Functional Roles in Cellular Processes

RAB5A regulates critical cellular pathways, including:

Endosomal Trafficking

• Early Endosome Fusion: RAB5A is required for plasma membrane-early endosome fusion and subsequent vesicle transport .

• Rab Conversion: Activated RAB5A recruits effectors (e.g., Rabenosyn-5) to mediate Rab5-to-Rab7 conversion, enabling endosome maturation .

Immune Regulation

• C5aR1 Internalization: In macrophages, RAB5A facilitates internalization of the complement C5a receptor (C5aR1) via early endosomes, modulating inflammatory responses .

Cancer Progression

• Gastric Cancer (GC): Overexpression of RAB5A correlates with advanced GC stages, metastasis, and proliferation. Co-localization with RAB4A enhances endosomal recycling of growth factors like EGF, promoting malignancy .

• Breast Cancer: High RAB5A expression predicts sensitivity to trastuzumab emtansine (T-DM1), an antibody-drug conjugate, by enhancing drug internalization .

Autophagy and Vesicular Transport

• Exosomal Release: RAB5A regulates exosome secretion (e.g., syndecan, SDCBP) and autophagosome maturation in cancer cells .

Applications in Research and Diagnostics

RAB5A antibodies are widely used in:

Gastric Cancer (GC)

Mechanism: RAB5A overexpression enhances EGF-induced proliferation via RAB4A co-localization, promoting endosomal recycling of growth factors .

Breast Cancer and ADC Response

• T-DM1 Sensitivity: High RAB5A expression correlates with pathologic complete response (pCR) in HER2+ breast cancer patients treated with T-DM1/pertuzumab .

• Biomarker Potential: RAB5A levels stratify patients into responsive (high) and non-responsive (low) groups, validated in I-SPY2 and KAMILLA trials .

Antibody Specificity and Validation

Commercial antibodies undergo rigorous validation:

1. Immunogen Design: Targeting conserved regions (e.g., aa 1–C-terminus) ensures cross-species reactivity .

2. Purification: Affinity-purified using protein A/G or antigen columns .

3. Controls: Preimmune IgG or peptide-blocking experiments confirm specificity .

Example Validation Data

• GeneTex GTX109665 (Rabbit Polyclonal):

  • WB: Detects 24 kDa RAB5A in HeLa, Neuro2A, and Raw264.7 lysates .

  • IP: Pulls down RAB5A from HeLa lysates without cross-reactivity .

• Proteintech 66339-1-Ig (Mouse Monoclonal):

  • IHC: Stains early endosomes in cancer tissues .