Cell surface antigen expression on chemically induced murine leukaemias

Area of Science:

• Immunology
• Oncology
• Carcinogenesis

Background:

• Investigating the immunogenicity of chemically induced murine leukemias is crucial for understanding tumor antigen presentation.
• Previous studies suggest potential alterations in cell-surface antigens on tumor cells, affecting immune recognition.

Purpose of the Study:

• To evaluate the immunogenicity of chemically induced murine leukemias.
• To determine the expression of H-2 histocompatibility antigens on leukemia cells.
• To explore the implications for detecting tumor neoantigens.

Main Methods:

• In vivo transplantation assays to assess leukemia rejection by immunized syngeneic mice.
• In vitro indirect membrane immunofluorescence (IF) using syngeneic and allogeneic antisera.
• Alloantibody absorption assays to quantify H-2 antigen expression.

Main Results:

• Two out of five tested leukemias exhibited weak neoantigenicity; three were non-immunogenic.
• H-2 histocompatibility antigens were undetectable on most primary and transplanted leukemias.
• Transplantation to allogeneic recipients induced a humoral response against normal lymphoid cells, suggesting modified H-2 expression on leukemia cells.

Conclusions:

• Chemically induced murine leukemia cells display significantly modified H-2 antigen expression.
• This modification poses challenges for detecting tumor neoantigens using standard immunologic methods.
• Findings highlight the importance of considering antigen modulation in cancer immunology research.