A Human Dectin-2 Deficiency Associated With Invasive Aspergillosis

Area of Science:

• Immunology
• Mycology
• Genetics

Background:

• Invasive aspergillosis poses a significant threat to immunocompromised individuals.
• Dectin-2 is a fungal-binding receptor crucial for immune responses against Aspergillus species.

Observation:

• A homozygous deletion mutation (507 del C) was identified in the Dectin-2 receptor gene of an immunocompromised patient.
• The mutation resulted in a frameshift (N170I) and an early stop codon, leading to a defective Dectin-2 receptor.

Findings:

• The mutated Dectin-2 receptor showed weak expression, failed to cluster, and was functionally impaired.
• Peripheral blood mononuclear cells from the patient did not produce key cytokines (tumor necrosis factor, interleukin 6) in response to Aspergillus fumigatus.
• This represents the first identified case of Dectin-2 deficiency.

Implications:

• Dectin-2 plays a critical role in the innate immune defense against invasive aspergillosis.
• Dectin-2 deficiency can lead to severe, life-threatening fungal infections.
• Understanding Dectin-2 function is vital for developing targeted therapies for immunocompromised patients at risk of aspergillosis.