Thyroid hormone metabolism in innate immune cells

Area of Science:

• Immunology
• Endocrinology
• Cell Biology

Background:

• Thyroid hormone (TH) status impacts immune responses, particularly innate immunity.
• While effects on innate immune cells are known, intracellular TH metabolism's role is newly explored.
• Focus is on neutrophils, macrophages, and dendritic cells.

Purpose of the Study:

• Review intracellular TH metabolism in innate immune cells.
• Elucidate TH's role in innate immune cell function during inflammation.
• Highlight TH metabolism's significance in host defense.

Main Methods:

• Literature review of molecular machinery for intracellular TH metabolism.
• Analysis of genomic and non-genomic effects of TH.
• Examination of deiodinase enzymes and TH receptors in immune cells.

Main Results:

• Circulating TH levels significantly affect innate immune cell function.
• Elevated TH levels generally amplify pro-inflammatory responses.
• Intracellular TH metabolism is essential for cellular responses to inflammation.

Conclusions:

• Intracellular TH metabolism is vital for innate immune cell function.
• Deiodinase enzymes and TH receptors are critical for immune cell adequacy.
• TH metabolism plays a key role in host defense via immune cell modulation.