DEVELOPING AN IN VITRO MODEL OF INFECTION OF BOVINE B CELLS WITH BLV

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 牛白血病病毒(BLV)是一种感染牛的逆转录病毒。它与人类T细胞白血病病毒密切相关。然而，BLV主要感染B细胞，而不是T细胞。BLV在大约5%的受感染动物中会导致B细胞淋巴肉瘤，但也会在更大比例的受感染牛中引起持续性淋巴细胞增多症和其他健康问题。在以前的出版物中，Isaacson等人。报道称，实验感染BLV的牛对各种非BLV抗原的抗体应答增强，并发现这些动物的B细胞表达MHC-II分子的数量显著增加。到目前为止，BLV阴性的牛淋巴肉瘤(BL-3)细胞与BLV感染的Flk-BLV细胞的无细胞培养上清液孵育已导致BL-3细胞的BLV聚合酶链式反应阳性。这些结果目前正在得到证实，并正在研究各种定量测定Flk-BLV上清液中BLV的方法。到目前为止，通过逆转录酶试验以及使用对BLV敏感的CC81细胞的TCID50试验来确定BLV滴度的尝试都没有成功，但努力仍在继续。此外，BLV感染的BL-3细胞将很快被流式细胞仪检测，以确定在体外BLV感染后MHC-II的表达水平是否增加。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Bovine leukemia virus (BLV) is a retrovirus that infects cattle. It is closely related to the human T cell leukemia virus. However, BLV mainly infects B cells, rather than T cells. BLV causes a B cell lymphosarcoma in about 5% of infected animals, but can also cause persistent lymphocytosis and other health problems in a larger percentage of infected cattle. In previous publications, Isaacson et al. reported that cattle experimentally infected with BLV had increased antibody responses to various non-BLV antigens, and a significantly increased number of B cells from these animals were found to express MHC-II molecules. To date, incubation of BLV-negative bovine lymphosarcoma (BL-3) cells with cell-free supernatants from BLV-infected FLK-BLV cells has resulted in the BL-3 cells becoming PCR-positive for BLV. These results are currently being confirmed, and various methods for quantitation of BLV in FLK-BLV supernatants are being investigated. Thus far, attempts to determine BLV titers by a reverse transcriptase assay, as well as by a TCID50 assay using BLV-susceptible CC81 cells, have been unsuccessful, but efforts are continuing. In addition, the BLV-infected BL-3 cells will soon be assayed by flow cytometry to determine whether levels of MHC-II expression are increased following in vitro BLV infection.