Cancer Immunology, Immunotherapy

, Volume 62, Issue 6, pp 1107–1122 | Cite as

Monoclonal antibodies toward different Tn-amino acid backbones display distinct recognition patterns on human cancer cells. Implications for effective immuno-targeting of cancer

  • Daniel Mazal
  • Richard Lo-Man
  • Sylvie Bay
  • Otto Pritsch
  • Edith Dériaud
  • Christelle Ganneau
  • Andrea Medeiros
  • Luis Ubillos
  • Gonzalo Obal
  • Nora Berois
  • Mariela Bollati-Fogolin
  • Claude Leclerc
  • Eduardo Osinaga
Original Article


The Tn antigen (GalNAcα-O-Ser/Thr) is a well-established tumor-associated marker which represents a good target for the design of anti-tumor vaccines. Several studies have established that the binding of some anti-Tn antibodies could be affected by the density of Tn determinant or/and by the amino acid residues neighboring O-glycosylation sites. In the present study, using synthetic Tn-based vaccines, we have generated a panel of anti-Tn monoclonal antibodies. Analysis of their binding to various synthetic glycopeptides, modifying the amino acid carrier of the GalNAc(*) (Ser* vs Thr*), showed subtle differences in their fine specificities. We found that the recognition of these glycopeptides by some of these MAbs was strongly affected by the Tn backbone, such as a S*S*S* specific MAb (15G9) which failed to recognize a S*T*T* or a T*T*T* structure. Different binding patterns of these antibodies were also observed in FACS and Western blot analysis using three human cancer cell lines (MCF-7, LS174T and Jurkat). Importantly, an immunohistochemical analysis of human tumors (72 breast cancer and 44 colon cancer) showed the existence of different recognition profiles among the five antibodies evaluated, demonstrating that the aglyconic part of the Tn structure (Ser vs Thr) plays a key role in the anti-Tn specificity for breast and colon cancer detection. This new structural feature of the Tn antigen could be of important clinical value, notably due to the increasing interest of this antigen in anticancer vaccine design as well as for the development of anti-Tn antibodies for in vivo diagnostic and therapeutic strategies.


Tn antigen O-glycosylation Cancer Immunotherapy Vaccine Antibody 

Supplementary material

262_2013_1425_MOESM1_ESM.pdf (567 kb)
Supplementary material 1 (PDF 567 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Daniel Mazal
    • 1
  • Richard Lo-Man
    • 2
    • 3
  • Sylvie Bay
    • 4
    • 5
  • Otto Pritsch
    • 6
    • 7
  • Edith Dériaud
    • 2
    • 3
  • Christelle Ganneau
    • 4
    • 5
  • Andrea Medeiros
    • 8
  • Luis Ubillos
    • 6
  • Gonzalo Obal
    • 6
    • 7
  • Nora Berois
    • 9
  • Mariela Bollati-Fogolin
    • 10
  • Claude Leclerc
    • 2
    • 3
  • Eduardo Osinaga
    • 6
    • 9
  1. 1.Departamento de Anatomía Patológica y Citología del Hospital de la MujerCentro Hospitalario Pereira RossellMontevideoUruguay
  2. 2.Unité de Régulation Immunitaire et VaccinologieInstitut PasteurParisFrance
  3. 3.Institut National de la Santé et de la Recherche MédicaleParisFrance
  4. 4.Unité de Chimie des BiomoléculesInstitut PasteurParisFrance
  5. 5.Centre National de la Recherche Scientifique UMR 3523ParisFrance
  6. 6.Departamento de Inmunobiologia, Facultad de MedicinaUniversidad de la RepúblicaMontevideoUruguay
  7. 7.Unidad de Biofísica de ProteínasInstitut Pasteur de MontevideoMontevideoUruguay
  8. 8.Departamento de Bioquímica, Facultad de MedicinaUniversidad de la RepúblicaMontevideoUruguay
  9. 9.Laboratorio de Glicobiología e Inmunología TumoralInstitut Pasteur de MontevideoMontevideoUruguay
  10. 10.Unidad de Biología CelularInstitut Pasteur de MontevideoMontevideoUruguay

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