Characterization of Porcine Monocyte-Derived Macrophages Cultured in Serum-Reduced Medium

Area of Science:

• Veterinary Immunology
• Cell Biology
• Biotechnology

Background:

• Fetal bovine serum (FBS) is crucial for cell culture but its use is increasingly scrutinized.
• Developing reduced-serum methods for porcine monocyte-derived macrophages (MDMs) is essential for sustainable research.
• Variability in FBS from different suppliers can influence cell behavior and experimental outcomes.

Purpose of the Study:

• To establish a reduced-serum cell culture system for generating porcine MDMs.
• To compare the effects of a reduced-serum supplement (Nu-Serum™ Growth Medium Supplement - NUS) versus conventional FBS.
• To evaluate the impact of FBS from two different providers (FBS1 and FBS2) on MDM characteristics.

Main Methods:

• Porcine peripheral blood mononuclear cells were cultured under reduced-serum (NUS) and conventional FBS conditions.
• Two different FBS lots (FBS1 and FBS2) were assessed.
• Key macrophage markers (IL-1β, CD86, IL-23p19, CXCL10, CCL5, CD14, CD16, CD163, CD80, IL-10) and functions (phagocytosis, respiratory burst) were analyzed via mRNA expression and activity assays.

Main Results:

• Reduced-serum conditions induced a proinflammatory cytokine profile (increased IL-1β, CD86, IL-23p19, CXCL10, CCL5 mRNA) without compromising phagocytic or respiratory burst activity.
• FBS source had a more significant impact than serum reduction.
• FBS1 cultures yielded macrophages with higher CD14, CD16, CD163 surface levels, lower CD80 mRNA, and increased IL-10 gene expression.
• FBS2 cultures showed increased IL-1β and CD86 mRNA, unlike FBS1.
• No significant differences were observed in phagocytic or respiratory burst activities between conditions.

Conclusions:

• Reduced-serum culture is a viable method for generating porcine MDMs.
• The source of FBS is a critical factor influencing porcine MDM phenotype and function.
• This study supports the trend of reducing FBS usage in biological research while highlighting the importance of FBS lot selection.