Expanded clinical and experimental use of SOX11 - using a monoclonal antibody

Abstract

BackgroundThe transcription factor SOX11 is of diagnostic and prognostic importance in mantle cell lymphoma (MCL) and epithelial ovarian cancer (EOC), respectively. Thus, there is an unmet clinical and experimental need for SOX11-targeting assays with low background, high specificity and robust performance in multiple applications, including immunohistochemistry (IHC-P) and flow cytometry, which until now has been lacking.MethodsWe have developed SOX11-C1, a monoclonal mouse antibody targeting SOX11, and successfully evaluated its performance in western blots (WB), IHC-P, fluorescence microscopy and flow cytometry.ResultsWe confirm the importance of SOX11 as a diagnostic antigen in MCL as 100% of tissue micro array (TMA) cases show bright nuclear staining, using the SOX11-C1 antibody in IHC-P. We also show that previous reports of weak SOX11 immunostaining in a fraction of hairy cell leukemias (HCL) are not confirmed using SOX11-C1, which is consistent with the lack of transcription. Thus, high sensitivity and improved specificity are demonstrated using the monoclonal SOX11-C1 antibody. Furthermore, we show for the first time that flow cytometry can be used to separate SOX11 positive and negative cell lines and primary tumors. Of note, SOX11-C1 shows no nonspecific binding to primary B or T cells in blood and thus, can be used for analysis of B and T cell lymphomas from complex clinical samples. Dilution experiments showed that low frequencies of malignant cells (~1%) are detectable above background using SOX11 as a discriminant antigen in flow cytometry.ConclusionsThe novel monoclonal SOX11-specific antibody offers high sensitivity and improved specificity in IHC-P based detection of MCL and its expanded use in flow cytometry analysis of blood and tissue samples may allow a convenient approach to early diagnosis and follow-up of MCL patients.

Sox11 expression in astrocytic gliomas: correlation with nestin/c-Met/IDH1-R132H expression phenotypes, p-Stat-3 and survival

“…The pattern of staining was nuclear, as reported by other investigators in foetal brain tissue (Haslinger et al , 2009), mantle cell lymphoma (Nordström et al , 2012), ovarian carcinoma (Brennan et al , 2009) and medulloblastoma (de Bont et al , 2008), conforming to the nuclear localisation signals conserved among all Sox proteins. Indeed, the lack of nuclear staining reportedly correlates with the absence of Sox11 mRNA in normal and neoplastic tissues (Ek et al , 2008).…”

763 Expanded Clinical and Experimental Use of SOX11 – Using a Monoclonal Antibody

“…Proteins were blotted onto a PVDF membrane with the iBlot W Dry Blotting System (Invitrogen) and the membrane was blocked in 5% milk/PBS. SOX11 expression Sequence was originally derived from the HPR project as previously described [35]. was assessed using SOX11-C1 at a final concentration of 1 μg/ml in 5% milk/PBS.…”

Emerging role of SOX11 in mantle cell lymphoma

“…Furthermore, as most studies use IHC to assess SOX11 expression, it is worth mentioning that tissue fixation time could have a large impact on the staining intensity. Also, most studies have assessed SOX11 expression using polyclonal reagents, which display a potential cross-reactivity to SOX4 50 and/or suffer from batch variations. Thus, current literature supports the use of specific monoclonal SOX11 antibodies that today are present on the market.…”

“…It has further been suggested that SOX11 may be used as a marker for minimal residual disease. 50 Analysis of SOX11 protein, being highly homologous to other SOX4 and SOX12, has been hampered by unspecific tools and only recently a specific monoclonal antibody was developed. 50 The superiority of this antibody has also been confirmed by independent users.…”

“…50 Analysis of SOX11 protein, being highly homologous to other SOX4 and SOX12, has been hampered by unspecific tools and only recently a specific monoclonal antibody was developed. 50 The superiority of this antibody has also been confirmed by independent users. 52 Thus, current literature should be carefully interpreted to acknowledge that analysis may include background levels of other SOX family proteins.…”