Theileria annulata is a protozoan parasite transmitted by ticks to cattle. The most important processes of T. annulata are the infection and transformation of host monocytes, which promote cell division and generate a neoplastic phenotype. Dendritic cells play an important role in the development of adaptive immune responses against parasites and are traditionally classified into four types. One type of dendritic cell derived from afferent lymph was successfully transformed by T. annulata in vitro in a previous report. However, whether the monocyte-derived dendritic cells could be transformed and how the endocytic function is affected by T. annulata infection were not yet known. Bovine dendritic cells (DCs) derived from blood CD14⁺ monocytes were cocultured with T. annulata sporozoites in vitro. On day 15 post infection, rounded and continuously proliferating cells were observed. The effect of this transformation on cell phenotype was studied using immunostaining and flow cytometry. After transformation, the cells maintained the expression of the DC-specific marker CD11c, but it was downregulated as were the expression of CD11b, CD14 and CD86. In contrast, CD205, CD45 and MHC class Ⅱ molecules were upregulated in transformed cells. The levels of CD172a, CD21, CD40 and CD80 expression were very low in the transformed cells (<1 %). However, the transformed cells maintained high expression levels of MHC Ⅰ (>99 %). In addition, the normal and transformed DCs were cocultured with OVA-FITC antigen to compare the differences of the endocytic functions between these two types of cells. The results revealed that the endocytic functions of MoDCs were significantly inhibited after transformation by T. annulata.

环状泰勒虫是通过tick传播给牛的原生动物寄生虫。环线虫最重要的过程是宿主单核细胞的感染和转化，它们促进细胞分裂并产生肿瘤表型。树突状细胞在针对寄生虫的适应性免疫反应的发展中起重要作用，传统上分为四种类型。在以前的报道中，一种由传入淋巴液衍生的树突状细胞在体外成功地被环孢菌转化。但是，尚不知道单核细胞来源的树突状细胞是否可以被转化，以及环虫感染如何影响内吞功能。源自血液CD14 ^+的牛树突状细胞（DCs）单核细胞与环线虫共培养子孢子体外。感染后第15天，观察到圆形和连续增殖的细胞。使用免疫染色和流式细胞仪研究了这种转化对细胞表型的影响。转化后，细胞维持DC特异性标记CD11c的表达，但CD11b，CD14和CD86的表达下调。相反，CD205，CD45和MHCⅡ类分子在转化细胞中被上调。在转化细胞中，CD172a，CD21，CD40和CD80的表达水平非常低（<1％）。然而，转化的细胞保持了MHCⅠ的高表达水平（> 99％）。另外，将正常的和转化的DC与OVA-FITC抗原共培养以比较这两种类型的细胞之间的内吞功能的差异。T.菇。