A rabbit monoclonal antibody against the antiviral and cancer genomic DNA mutating enzyme APOBEC3B

Abstract

The DNA cytosine deaminase APOBEC3B (A3B) is normally an antiviral factor in the innate immune response. However, A3B has been implicated in cancer mutagenesis, particularly in solid tumors of the bladder, breast, cervix, head/neck, and lung. Here, we report data on the generation and characterization of a rabbit monoclonal antibody (mAb) for human A3B through a series of immunoblot, immunofluorescence microscopy, and immunohistochemistry experiments. Positive results indicate that one mAb, 5210-87-13, will be useful for fundamental research in virology and cancer biology and that immunohistochemical quantification of A3B enzyme levels may constitute a clinical biomarker for tumor evolvability and differential treatment.

Human APOBEC3B promotes tumor heterogeneityin vivoincluding signature mutations and metastases

“…IHC clearly shows a strong accumulation of human A3B in the nuclear compartment of cells in multiple murine tissues, consistent with prior reports for human A3B subcellular localization in human cell lines and tissues. [17][18][19][20] These observations demonstrate that higher levels of human A3B are tolerated in primary mouse tissues and, further, that its nuclear import mechanism is conserved, despite the fact that only distantly related polynucleotide deaminase family members are expressed in mice (i.e., Apobec3, Apobec1, and Aicda).…”

“…IHC was performed as described with minor modifications. 17,46,47 Formalin-fixed paraffinembedded tissues were sectioned into 4-µm-thick slices and mounted on positively charged adhesive slides. They were then baked at 65°C for 20 minutes to deparaffinize and then rehydrated with three consecutive washes in CitriSolv (Decon Labs) for 5 min each followed by graded alcohols as above, followed by a final 5 min wash in running water.…”