Author/Authors :
Mahmoudian, Jafar Nanotechnology Research Center - Faculty of Pharmacy - Tehran University of Medical Sciences (TUMS) - Tehran, Iran , Nazari, Mahboobeh Monoclonal Antibody Research Center - Avicenna Research Institute (ACECR) - Tehran, Iran , Ghods, Roya Oncopathology Research Center - Iran University of Medical Sciences (IUMS) - Tehran, Iran , Jeddi-Tehrani, Mahmood Monoclonal Antibody Research Center - Avicenna Research Institute (ACECR) - Tehran, Iran , Ostad, Nasser Nanotechnology Research Center - Faculty of Pharmacy - Tehran University of Medical Sciences (TUMS) - Tehran, Iran , Ghahremani, Mohammad Hossein Nanotechnology Research Center - Faculty of Pharmacy - Tehran University of Medical Sciences (TUMS) - Tehran, Iran , Vafaei, Sedigheh Reproductive Immunology Research Center - Avicenna Research Institute - (ACECR) - Tehran, Iran , Amiri, Mohammad Mehdi Department of Immunology - School of Public Health - Tehran University of Medical Sciences (TUMS) - Tehran, Iran , Zarnani, Amir-Hassan Department of Immunology - School of Public Health - Tehran University of Medical Sciences (TUMS) - Tehran, Iran
Abstract :
Placenta-specific 1 (PLAC1), as a new Cancer/Testis Antigen (CTA), is
frequently expressed in a variety of cancers and localized to cytoplasm and plasma
membrane. Surface expression of cancer target antigens is of great importance that
enables antibody-mediated cancer immunotherapy. The aim of the current study
was to express the intact human PLAC1 protein on plasma membrane of a eukaryotic
cell as a model for future anti-PLAC1-based cancer immunotherapy.
Methods: In the first approach, entire human PLAC1 gene including its own Signal
Peptide (SP) was cloned into pIRES2-EGFP and LeGO-iG2 vectors and expressed in
CHO-K1 cells. In the second approach, cytosolic and Signal-Anchor (SA) sequence of
Transferrin Receptor Protein 1 (TFR1) were fused to extracellular portion of PLAC1 and
expressed as above. Expression of PLAC1 was then assessed using Reverse Transcription
Polymerase Chain Reaction (RT-PCR), Western Blot (WB), Immunocytochemistry
(ICC), Immunofluorescence (IF) and Flow Cytometry (FC).
Results: The first approach resulted in the expression of PLAC1 in submembranous but
not in the surface of transfected CHO-K1 cells. Using the chimeric human PLAC1 construct,
the same intracellular expression pattern was observed.
Conclusion: These results indicated that there are some yet unknown PLAC1 localization
signals employed by cancer cells for surface expression of PLAC1.
