Effect of intraperitoneal prosthetic materials on reticuloendothelial function in the rat

Area of Science:

• Biomaterials Science
• Immunology
• Surgical Research

Background:

• The reticuloendothelial system (RES) plays a crucial role in immune surveillance and clearance of foreign particles.
• Bacterial translocation, the movement of bacteria from the gut to systemic sites, is a significant concern in surgical and critically ill patients.
• Prosthetic biomaterials implanted intraperitoneally may influence RES function and potentially lead to bacterial translocation.

Purpose of the Study:

• To investigate the effects of different intraperitoneal prosthetic biomaterials on RES function in rats.
• To evaluate the incidence and extent of bacterial translocation following implantation of various biomaterials.
• To determine if biomaterial surface area influences RES function and bacterial translocation.

Main Methods:

• Rats were implanted with rubber drains, knitted Dacron (KD), or silicone elastomer (SE) biomaterials of varying surface areas (3 cm2 or 10 cm2) or underwent sham operations.
• RES function was assessed by measuring the phagocytic index and the uptake of 125I-labeled Escherichia coli in systemic organs and gut-associated lymphoid tissues (GALT).
• Bacterial translocation was assessed by culturing samples from various organs.

Main Results:

• Implantation of prosthetic biomaterials significantly elevated the phagocytic index in most groups compared to controls.
• Uptake of labeled E. coli increased in systemic organs but decreased in GALT, indicating a shift in immune cell activity.
• Indigenous bacterial translocation to mesenteric lymph nodes, liver, spleen, lungs, and kidneys was observed, with a size-dependent effect of biomaterials.

Conclusions:

• Intraperitoneal prosthetic biomaterials significantly alter host RES function.
• These biomaterials induce bacterial translocation from the gut to systemic organs.
• The surface area of the implanted biomaterial plays a role in modulating RES function and the incidence of bacterial translocation.