Lactoferrin content of peripheral blood cells

Area of Science:

• Immunology
• Hematology
• Biochemistry

Background:

• Lactoferrin is an iron-binding protein with antimicrobial and immunomodulatory functions.
• Its distribution and forms in human peripheral blood cells and plasma are not fully characterized.

Purpose of the Study:

• To quantify lactoferrin and lysozyme in various peripheral blood components.
• To investigate sex and menopausal status differences in neutrophil lactoferrin.
• To explore lactoferrin's cellular localization and molecular forms.

Main Methods:

• Peripheral blood separation into plasma, red cells, neutrophils, lymphocytes, monocytes, and platelets.
• Lactoferrin and lysozyme concentration measurements.
• Immunofluorescence microscopy for cellular localization.
• Gel chromatography (Sephadex G-200) for molecular form analysis.

Main Results:

• Neutrophil lactoferrin content was significantly higher in males and post-menopausal females than in pre-menopausal females.
• Lactoferrin was detected in monocytes and neutrophils, but not in lymphocytes, erythrocytes, or platelets.
• Immunofluorescence confirmed a lactoferrin surface receptor on monocytes.
• Gel chromatography revealed lactoferrin in neutrophils and plasma exists in polymerized or complexed forms.

Conclusions:

• Neutrophil lactoferrin levels exhibit variations based on sex and menopausal status.
• Monocytes possess surface receptors for lactoferrin.
• Lactoferrin in neutrophils and plasma exists in complexed forms, suggesting functional implications.