Extracellular vesicles engineered to bind albumin demonstrate extended circulation time and lymph node accumulation...

Area of Science:

• Biotechnology
• Nanomedicine
• Drug Delivery

Background:

• Extracellular vesicles (EVs) show therapeutic promise but suffer from rapid clearance.
• Engineering EVs to bind albumin can overcome limitations in circulation time.

Purpose of the Study:

• To engineer EVs with enhanced serum albumin binding for prolonged circulation and improved therapeutic delivery.
• To investigate the biodistribution and accumulation of engineered EVs in vivo.

Main Methods:

• Surface display of albumin binding domains (ABDs) on EVs using tetraspanins (CD63, CD9, CD81) or Lamp2B.
• In vitro binding assays with human serum albumin (HSA).
• In vivo studies in mice to assess circulation time, biodistribution, and accumulation in lymph nodes and tumors.

Main Results:

• Engineered EVs demonstrated robust binding to HSA in vitro and mouse serum albumin (MSA) in vivo.
• EV circulation time significantly increased after various administration routes in mice.
• Engineered EVs showed notable accumulation in lymph nodes and solid tumors.

Conclusions:

• EV surface engineering with ABDs effectively prolongs circulation time by binding serum albumin.
• Enhanced EV accumulation in lymph nodes and tumors offers potential for targeted immunomodulation, cancer therapy, and immunotherapy.
• This strategy holds significant promise for improving the therapeutic efficacy of EVs across diverse disease indications.