Molecular and Immunophenotypical Characterization of a Feline Immunodeficiency Virus (FIV)-Associated Lymphoma: a Direct Role for FIV in B-Lymphocyte Transformation?

We describe the histopathological, immunohistochemical, and molecular characterization of a lymphoma arising in a 7-year-old cat following experimental infection with feline immunodeficiency virus (FIV). The tumor was high grade and of B-cell lineage. The transformed cell had an immature phenotype (CD79a(+), CD79b(−), CD21(−), immunoglobulin heavy and light chain negative), confirmed by antigen receptor gene analysis, which showed germ line configuration. Single-copy, clonally integrated FIV provirus was detected in tumor genomic DNA. FIV p24 antigen was not detected in tumor cells by immunostaining. This study provides the first evidence that the feline lentivirus may play a direct role in cell transformation under certain circumstances.

本研究描述了一只7岁家猫在实验性感染猫免疫缺陷病毒（Feline Immunodeficiency Virus, FIV）后发生的淋巴瘤的组织病理学、免疫组织化学与分子特征。该肿瘤为高级别B细胞源性淋巴瘤。经抗原受体基因分析证实，转化细胞呈现未成熟表型（CD79a阳性、CD79b阴性、CD21阴性，免疫球蛋白重链及轻链均呈阴性），且分析结果显示其基因呈种系构型。在肿瘤基因组DNA中检测到单拷贝、克隆整合的FIV前病毒。免疫染色未在肿瘤细胞中检测到FIV p24抗原。本研究首次提供证据表明，在特定条件下，猫慢病毒可直接参与细胞转化过程。