Immunohistochemical characterization of novel murine monoclonal antibodies against human placenta-specific 1.
Human PLAC1 (placenta-specific 1) is a new member of cancer-testis antigens with 212 amino acids, and its expression is restricted to placenta and at much lower levels to testis. Recently, ectopic expression of the PLAC1 transcript has been demonstrated in a wide range of human tumors and cancer cell lines with a proposed function in tumor cell growth. No monoclonal anti-PLAC1 antibody applicable to immunohis-tochemical staining is available so far. To better understand the PLAC1 expression and localization, we aimed to produce monoclonal antibodies (mAbs) against the extracellular region of PLAC1. Mice were immunized with a synthetic peptide corresponding to the C-terminal 11 amino acids of PLAC1 conjugated with a carrier protein. Hybridomas were produced by standard protocol and screened for positive reactivity by enzyme-linked immunosorbent assay. Reactivity of final two clones was then assessed by Western blotting (WB), immunohistochemistry (IHC), and immunocytochemistry (ICC). Both clones showed a specific immunostaining pattern in human term placenta as the positive control. Reactivity was mostly localized to the cytoplasm of syncytiotrophoblasts. One of the clones showed an excellent staining signal in breast, ovary, and prostate cancer cell lines. Importantly, no reactivity was observed with human lymph node cells or prostate. None of the mAbs were able to detect PLAC1 in Western blot. Based on the present results, these mAbs can be used for detection of PLAC1 in IHC and ICC techniques.
Department of Molecular Medicine, School of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran, Iran; Monoclonal Antibody Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.
Roya
R
Ghods
Mohammad Hossein
MH
Ghahremani
Maryam
M
Darzi
Ahmad-Reza
AR
Mahmoudi
Omid
O
Yeganeh
Ali Ahmad
AA
Bayat
Parvin
P
Pasalar
Mahmood
M
Jeddi-Tehrani
Amir-Hassan
AH
Zarnani
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000937:Antigen-Antibody Reactions; D000951:Antigens, Neoplasm / Q000276:immunology; D006801:Humans; D007150:Immunohistochemistry; D061986:MCF-7 Cells; D051379:Mice; D011257:Pregnancy Proteins / Q000276:immunology*; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; C415583:PLAC1 protein, human; D011257:Pregnancy Proteins
Anti-PLAC1; PLAC1; immunohistochemistry; monoclonal antibody; placenta