Heterophile antibody interference associated with natural killer cell therapy

Area of Science:

• Immunology
• Clinical Chemistry
• Oncology

Background:

• Adoptive transfer of ex vivo-expanded natural killer (NK) cells is an emerging cancer treatment.
• The safety and potential laboratory interferences of NK cell therapy are not well-characterized.

Purpose of the Study:

• To investigate the cause of falsely elevated parathyroid hormone (PTH) and thyroglobulin levels in patients undergoing NK cell therapy.
• To assess the persistence and resolution of laboratory abnormalities following NK cell therapy.

Main Methods:

• Evaluated three patients with elevated serum PTH and thyroglobulin levels post-autologous NK cell therapy.
• Measured hormone concentrations using standard assays and confirmed results with heterophile-blocking tubes (HBT).

Main Results:

• Patients exhibited falsely elevated serum PTH and thyroglobulin levels.
• Interference was attributed to heterophile antibodies induced by NK cell therapy, persisting up to 12 months.
• HBT treatment normalized hormone levels, confirming the interference.

Conclusions:

• NK cell therapy, potentially via mouse monoclonal antibodies, can induce heterophile antibodies causing laboratory test interference.
• Abnormal lab results in patients receiving NK cell therapy require evaluation for heterophile antibody interference to prevent misdiagnosis.