In human and different animal species, blood monocytes are classified based on their expression pattern of different monocytic markers into phenotypically and functionally different subsets. In the current study, we used flow cytometry and monoclonal antibodies to CD172a, CD14, CD163 and MHCII to identify monocyte subsets in peripheral blood of dromedary camels. Based on CD14, CD163 and MHCII expression, camel CD172a + monocytes were divided into three subsets: The major subpopulation of camel monocytes (mo-I) showed high expression of CD14 and CD163, but low expression of MHCII. A second subset of monocytes (mo-II) expressed highly all three markers, CD14, CD163 and MHCII. A third monocyte subset (mo-III) displayed low expression of CD14 and CD163 with high MHCII expression. While the two MHCIIhigh subsets (mo-II and mo-III) showed higher expression of CD11a in comparison to the MHCIIlow subset (mo-I), CD18 and CD11b were highest expressed on the two CD14high subsets (mo-I and mo-II). Bacterial stimulation of camel leukocytes identified mo-II cells as an antimicrobial monocyte subset with the highest phagocytic and ROS production capacity. The comparison of monocyte counts and phenotype between newborn calves and adult camels revealed significantly reduced numbers of mo-II cells in newborn animals. Monocytes of newborns expressed significantly more CD172a and CD163 molecules but less CD14 and MHCII molecules than monocytes of adult camels. Camel monocyte subsets, mo-I, mo-II and mo-III are counterparts of bovine classical, intermediate and non-classical monocytes respectively. The distribution of camel monocyte subsets is influenced by age.

中文翻译：

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单峰骆驼CD14^高MHCII^高单核细胞显示出炎性并在新生骆驼犊牛中减少

在人类和不同动物物种中，血液单核细胞根据它们在不同单核细胞标记物上的表达模式进行分类，分为表型和功能上不同的子集。在本研究中，我们使用流式细胞仪和针对CD172a，CD14，CD163和MHCII的单克隆抗体来鉴定单峰骆驼外周血中的单核细胞亚群。基于CD14，CD163和MHCII表达，骆驼CD172a +单核细胞被分为三个子集：骆驼单核细胞的主要亚群（mo-I）显示CD14和CD163的高表达，但MHCII的低表达。单核细胞的第二个亚群（mo-II）高度表达CD14，CD163和MHCII这三个标记。第三个单核细胞亚群（mo-III）显示出CD14和CD163的低表达以及高MHCII的表达。尽管两个MHCIIhigh高子集（mo-II和mo-III）与MHCIIlow低子集（mo-I）相比，CD11a的表达更高，但是CD18和CD11b在两个CD14high高子集（mo-I和mo-II）上的表达最高。 ）。骆驼白细胞的细菌刺激将mo-II细胞鉴定为具有最高吞噬能力和ROS生产能力的抗菌单核细胞亚群。新生牛犊和成年骆驼之间单核细胞计数和表型的比较表明，新生动物中的mo-II细胞数量明显减少。与成年骆驼的单核细胞相比，新生儿的单核细胞表达的CD172a和CD163分子明显多，而CD14和MHCII分子则少。骆驼单核细胞亚群mo-I，mo-II和mo-III分别对应于牛的经典，中间和非经典单核细胞。