Targeting Phospholipase D Genetically and Pharmacologically for Studying Leukocyte Function.

Area of Science:

• Cell Biology
• Biochemistry
• Immunology

Background:

• Phospholipase D (PLD) hydrolyzes phospholipids, generating phosphatidic acid (PA).
• PA is a crucial signaling molecule involved in cell growth, cell cycle progression, and cell motility.
• Leukocyte migration is vital in inflammatory processes and disease pathogenesis.

Purpose of the Study:

• To investigate the role of Phospholipase D (PLD) in leukocyte migration using genetic and pharmacological approaches.
• To elucidate the specific contributions of PLD1 and PLD2 isoforms in neutrophil and macrophage functions.
• To understand the molecular mechanisms of PLD in ischemia-reperfusion injury (IRI)-induced neutrophilia and atherosclerosis.

Main Methods:

• Utilized PLD1-knockout (KO) and PLD2-KO mice for genetic studies.
• Isolated and fluorescently labeled bone marrow neutrophils (BMN) for studying neutrophilia in IRI.
• Prepared bone marrow-derived macrophages (BMDM) from KO mice to assess cholesterol phagocytosis.
• Employed pharmacological PLD inhibitors to study isoform-specific functions in BMN and BMDM.

Main Results:

• Established a three-part methodology for targeting PLD in leukocyte models.
• Provided insights into PLD's involvement in neutrophil migration relevant to IRI.
• Investigated PLD's potential role in macrophage cholesterol phagocytosis, a key step in atherosclerosis.
• Differentiated the contributions of PLD1 and PLD2 to leukocyte functions.

Conclusions:

• The developed three-step approach enables a comprehensive understanding of PLD's molecular underpinnings in pathological conditions.
• PLD is implicated in IRI-associated neutrophilia and atherosclerosis progression.
• Further research into PLD function can inform therapeutic strategies for inflammatory diseases.