Bovine Lactoferrin Modulates Mononuclear Cell Activity in Human Palatine Tonsils.

Area of Science:

• Immunology
• Microbiology
• Gastroenterology

Background:

• Lactoferrin (LF) is a key protein in mucosal secretions, crucial for maintaining homeostasis.
• Palatine tonsils are the initial immune defense in the oral cavity, utilizing Toll-like receptors (TLRs) to detect pathogens.

Purpose of the Study:

• To investigate the effects of bovine lactoferrin (LF) on palatine tonsil immune cells.
• To examine LF's impact on immune cells stimulated by TLR7 (viral RNA mimic) and TLR9 (bacterial DNA mimic) ligands.

Main Methods:

• Mononuclear cells from palatine tonsils of patients with recurrent tonsillitis or IgA nephropathy were isolated.
• Cells were cultured with bovine LF and either TLR7 or TLR9 ligands.
• Immune cell activation, cytokine production, and relevant molecular markers were analyzed.

Main Results:

• Under TLR7 stimulation, LF enhanced plasmacytoid dendritic cells (pDCs), T-killer cells, and B cells without inducing inflammatory cytokines.
• Under TLR9 stimulation, LF suppressed pDCs, myeloid dendritic cells, T-helper cells, T-killer cells, B cells, and natural killer cells, reducing TNF-α and IL-6.
• LF decreased BAFF, APRIL, and galactose-deficient IgA1, which are implicated in IgA nephropathy pathogenesis.

Conclusions:

• Bovine LF may bolster antiviral immune responses in the tonsils.
• LF could promote immune tolerance to commensal bacteria in the tonsils.
• LF shows potential therapeutic benefits for managing viral infections, recurrent tonsillitis, and IgA nephropathy.