Immunologic properties differ in preterm infants fed olive oil vs soy-based lipid emulsions during parenteral nutrition

Background: In the first period of life, premature infants need parenteral nutrition. Lipid emulsions (LEs), which are a part of parenteral nutrition, are known as potent immunological modulators and may therefore influence the immune status of parenterally fed infants. The aim of the study was to compare tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-10 production in the peripheral blood mononuclear cells (PBMCs) of premature infants parenterally fed with 2 LEs: olive oil (OO) and soybean oil (SO). Methods: Premature infants born at <32 weeks' gestation and with a birth weight <1500 g were randomized in a double-blind method within the first 48 hours of life to receive 1 of 2 LEs: OO based or SO based. At baseline and after 14 days, blood samples were collected, and PBMCs were isolated and then cultured for 48 hours in medium only and in the presence of anti-CD3 antibodies. Results: Of 44 recruited infants, 38 completed the study, 18 in the OO group and 20 in the SO group. The cytokine synthesis profile before the LE introduction was the same in both groups (nonstimulated and anti-CD3-induced PBMC). In the succeeding 14 days of parenteral nutrition, TNF-alpha, IL-6, and IL-10 levels in nonstimulated PBMCs remained unchanged in both groups. In contrast, IL-6 production was significantly higher in the SO group. Conclusions: SO-based LE may promote an excess of IL-6 production, especially in the T cell-dependent way of PBMC activation (via anti-CD3). OO emulsion seems to be immunologically more neutral than SO emulsion.