Geburtshilfe Frauenheilkd 2014; 74 - FV_06_04
DOI: 10.1055/s-0034-1388584

Pregnancy – A natural vaccination against tumor-associated antigens of the breast?

M Boudewijns 1, A Krause 2, P Beckhove 2, C Sohn 1, C Domschke 1, F Schütz 1
  • 1Universitätsfrauenklinik, Heidelberg, Germany
  • 2Deutsches Krebsforschungszentrum, Heidelberg, Germany

Objectives: Epidemiological studies have demonstrated that parity is a factor associated with decreased lifetime risk of developing breast cancer. Coincidental, breast carcinomas overexpress a range of tumor associated antigenes (TAA) such as the carcinoembryonic antigen (CEA), Mucin-1, and Her2. The objective of our study was to identify the impact of pregnancy on the presence of TAA-specific T-cell immunity and the incidence leading to an induction of TAA-specific regulatory T-cells (Treg).

Methods: We monitored the existence of TAA-specific T-cells of altogether 52 healthy individuals and 65 patients diagnosed with breast cancer or ductal carcinoma in situ (DCIS) with an IFN-y ELIspot assay using peptides and proteins derived from well-characterized TAAs. To investigate the influence of regulatory Treg, we performed the Elispot before and after depletion of CD4+CD25+ Tregs.

Results: For healthy individuals, for patients with carcinoma in-situ and for patients with breast cancer, we observed a significantly higher TAA-specific T-cell reaction after prior pregnancy compared to nullipara, respectively before and after T-reg depletion. (p < 0,05).

The highest T-cell reaction was observed in patients with invasive breast cancer after prior pregnancy (p < 0,05)

Conclusions: The findings of our studies implicate a T-cell induced reaction of the immune system as a possible resason for the protective influence of pregnancy concerning breast cancer. Pregnancy might therefore be discussed as a natural vaccination against TAAs of the breast.