Review of T Helper 2-Type Inflammatory Diseases Following Immune Checkpoint Inhibitor Treatment.

Immune checkpoints are mechanisms that allow cancer cells to evade immune surveillance and avoid destruction by the body's immune system. Tumor cells exploit immune checkpoint proteins to inhibit T cell activation, thus enhancing their resistance to immune attacks. Immune checkpoint inhibitors, like nivolumab, work by reactivating these suppressed T cells to target cancer cells. However, this reactivation can disrupt immune balance and cause immune-related adverse events. This report presents a rare case of prurigo nodularis that developed six months after administering nivolumab for lung adenocarcinoma. While immune-related adverse events are commonly linked to T helper-1- or T helper-17-type inflammations, T helper-2-type inflammatory reactions, as observed in our case, are unusual. The PD-1-PD-L1 pathway is typically associated with T helper-1 and 17 responses, whereas the PD-1-PD-L2 pathway is linked to T helper-2 responses. Inhibition of PD-1 can enhance PD-L1 functions, potentially shifting the immune response towards T helper-1 and 17 types, but it may also influence T helper-2-type inflammation. This study reviews T helper-2-type inflammatory diseases emerging from immune checkpoint inhibitor treatment, highlighting the novelty of our findings.

A Case of Refractory Vernal Keratoconjunctivitis Showing Improvement after the Administration of Upadacitinib for the Treatment of Atopic Dermatitis.

Vernal keratoconjunctivitis is a persistent allergic ocular disease predominantly mediated by the T-helper 2 lymphocyte-associated immune response. The standard therapeutic approaches for vernal keratoconjunctivitis include topical corticosteroids and immunosuppressive eye drops. However, managing vernal keratoconjunctivitis with only topical treatments becomes challenging during seasonally exacerbated periods. Systemic treatments such as oral corticosteroids or cyclosporine may be alternative options. Recently, dupilumab's efficacy in refractory vernal keratoconjunctivitis treatment has been documented. Here, we report a case of refractory vernal keratoconjunctivitis coexisting with atopic dermatitis that rapidly improved after upadacitinib administration. An 18-year-old Japanese woman presented with atopic dermatitis, vernal keratoconjunctivitis, and hay fever. In winter, the patient experienced widespread erythema and escalated itching, leading to significant discomfort and insomnia. Owing to the difficulty in maintaining her current regimen, upadacitinib (15 mg), a Janus kinase inhibitor was initiated. After upadacitinib administration, the treatment-resistant vernal keratoconjunctivitis and erythema improved. Upadacitinib is beneficial in severe cases of atopic dermatitis. Consequently, in our case, upadacitinib may offer therapeutic benefits for refractory vernal conjunctivitis by improving the T-helper 1/2 type immune response, autoimmunity, and oxidative stress. To our knowledge, this is the first report suggesting the potential utility of upadacitinib in managing severe vernal conjunctivitis.