Aptamer- vs Fab-Conjugated Liposomes: A Comparative Study in Targeting Acute Myeloid Leukemia Cells

Area of Science:

• Nanomedicine
• Hematologic Malignancies
• Targeted Drug Delivery

Background:

• Acute Myeloid Leukemia (AML) is a blood cancer with poor prognosis despite current treatments.
• Targeted therapies are needed to improve efficacy and reduce systemic toxicity in AML treatment.
• CD33 antigen is a surface marker present on AML cells, making it a potential therapeutic target.

Purpose of the Study:

• To design and compare liposomal nanoparticles functionalized with DNA aptamers or fragment-antigen-binding (Fab) antibodies for targeting CD33 on AML cells.
• To evaluate the binding affinity, cellular uptake, and targeting efficiency of aptamer-conjugated liposomes (Apt-Lipm) versus Fab-conjugated liposomes (Fab-Lipm).

Main Methods:

• Preparation of Apt-Lipm and Fab-Lipm targeting the CD33 antigen on AML cells.
• Assessment of cellular uptake and binding affinity in CD33-positive AML cell lines.
• Investigation of intracellular distribution and endocytic pathways for Fab-Lipm.

Main Results:

• Fab-Lipm demonstrated significantly higher binding affinity and cellular uptake compared to Apt-Lipm.
• The study elucidated the intracellular pathways involved in Fab-Lipm uptake by AML cells.
• Fab-Lipm showed enhanced targeting efficiency for CD33-positive AML cells.

Conclusions:

• Fab-conjugated liposomal systems offer superior targeting precision for AML cells over aptamer-conjugated systems.
• This enhanced targeting capability holds promise for developing more effective therapeutic strategies against hematologic malignancies like AML.
• The findings support the potential of Fab-Lipm as a nanocarrier for targeted AML therapy.