Plasma substitute induced impairment of the reticuloendothelial system function

Area of Science:

• Immunology
• Pharmacology
• Physiology

Background:

• Plasma substitutes are crucial for volume replacement but can interact with the reticuloendothelial system (RES).
• Previous research suggests potential RES dysfunction following administration of these colloidal solutions.

Purpose of the Study:

• To investigate the impact and duration of RES dysfunction induced by various plasma substitutes.
• To assess the physiological consequences of RES impairment on the elimination of endotoxins and phagocytic activity.

Main Methods:

• Evaluated RES function in normal and burned mice using 51-Cr-rabbit red blood cells (RBCs) and Salmonella enteritidis endotoxin clearance assays.
• Assessed in vitro liver phagocytosis using 125-I-HSA aggregates and post-infusion plasma.
• Tested dextran 40, dextran 70, hydroxyethyl starch, gelatin, and PVP as plasma substitutes.

Main Results:

• Plasma substitutes significantly decreased RBC clearance and endotoxin elimination in both normal and burned mice.
• RES dysfunction persisted for up to 6 hours in burned mice.
• In vitro liver phagocytosis was not enhanced by plasma from animals treated with plasma substitutes, unlike allogeneic plasma.

Conclusions:

• Tested plasma expanders impair RES phagocytic function, likely by interfering with phagocytosis-promoting plasma factors.
• This temporary RES impairment can compromise critical functions such as pathogen and toxin clearance.
• The findings highlight potential risks to immune response and cellular debris removal following plasma substitute administration.