Natural killer cells in vernal keratoconjunctivitis

Area of Science:

• Immunology
• Ophthalmology

Background:

• Natural killer (NK) cells modulate innate and adaptive immune responses through cytokine release.
• NK cells are implicated in allergic asthma and atopic dermatitis.
• Their role in allergic conjunctivitis, specifically vernal keratoconjunctivitis (VKC), is currently unknown.

Purpose of the Study:

• To investigate the presence and quantity of NK cells in the blood and conjunctiva of patients with active VKC.
• To compare NK cell levels in VKC patients with healthy controls.

Main Methods:

• Study included six patients with active VKC and six healthy controls.
• Blood samples and conjunctival biopsies were analyzed.
• NK cells were quantified using flow cytometry (blood) and immunohistochemistry (conjunctiva).
• Clinical findings and conjunctival immune infiltrates were correlated with NK cell numbers.

Main Results:

• NK cells were significantly decreased in the blood of VKC patients compared to healthy subjects.
• Conversely, NK cells were significantly increased in the conjunctiva of VKC patients.

Conclusions:

• NK cells are a significant component of immune infiltrates in the VKC conjunctiva, alongside lymphocytes, eosinophils, and mast cells.
• These findings suggest a role for NK cells and innate immunity in regulating allergic reactions in VKC.
• Targeting NK cells may offer new therapeutic strategies for allergic inflammation in VKC.