A groundbreaking study from Tsinghua University has shed light on the role of Granzyme K, a specific protein secreted by a unique type of immune cell, in driving chronic sinus infections. This research, published in the esteemed Nature scientific journal, reveals that what was once thought to be a vital defender in the immune system may actually contribute to persistent inflammation and tissue damage associated with chronic sinusitis and nasal polyps.

The team, comprising researchers from Tsinghua University and Beijing Tongren Hospital, dedicated nearly a decade to investigating the complexities of immune responses. They identified Granzyme K (GZMK) as the primary agent exacerbating the conditions, challenging the conventional perception of various immune cells in defending against infections.

Dr. Zhang Luo from Beijing Tongren Hospital likened white blood cells to the body's defense army, where T lymphocytes represent elite forces. Within this cadre, memory CD8+ T cells occupy a critical niche, functioning similarly to specialized commandos adept at executing specific tasks.

Interestingly, these memory CD8+ T cells deviate from traditional immune responses by secreting Granzyme K rather than the more recognized Granzyme B. This action allows them to sidestep the typical antibody activation route, yet paradoxically, it leads to intensified tissue damage and inflammation, worsening chronic sinus conditions.

Chronic sinusitis and nasal polyps are prevalent conditions affecting millions globally, manifesting symptoms such as nasal congestion, loss of smell, and chronic headaches. Current treatment options mainly provide temporary relief, leading to recurrent episodes that significantly impact patients' quality of life.

The study points to GZMK as a promising new target for drug development. In experimental models, inhibiting the action of GZMK showed a significant reduction in inflammation, indicating its potential for therapeutic applications.

Professor Qi Hai from Tsinghua University articulated the future implications of the research, stating, In the future, medications targeting Granzyme K could help control inflammation and reduce recurrence. This approach holds the potential to revolutionize the therapeutic landscape for chronic sinusitis, nasal polyps, and related allergic diseases.

(Gong Zhe contributed to the story.)