CD19, immunoglobulin level, and varied anti-cytokine autoantibodies underline dichotomous susceptibility to types of infection in patients with thymomas

To characterize the infective susceptibilities in thymoma patients beyond the classic Good syndrome attribution.

Patient Recruitment: Thymoma patients were recruited from Singapore and South Korea, and their clinical information was reviewed.
Immunological Assessment: Immunological parameters including immunoglobulin levels and lymphocyte subsets were correlated with infection types.
Autoantibody Detection: Neutralizing autoantibodies against various cytokines were detected using direct ELISA.
Immune Signaling Analysis: Serum switch experiments and Western blotting were used to ascertain immune signaling pathway disruptions.

Thymoma patients displayed two distinct groups based on infection types: one with recurrent viral or Pneumocystis jirovecii infections and another with non-tuberculous mycobacterium or invasive infections.
The first group had low immunoglobulin levels and CD19+ B cells, while the second group had normal immunoglobulin levels and neutralizing autoantibodies against IL-12, IL-23, and IFN-α.
The presence of autoantibodies compromised critical immune signaling pathways.

The findings indicate that infection vulnerability in thymoma patients is not solely linked to hypogammaglobulinemia.

The study highlights distinct immune profiles in thymoma patients.