Takase Hinako, Watanabe Ayako, Yoshizawa Yasutaka, Kitami Madoka, Sato Ryoichi
Graduate School of Bio-Application and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei 2-24-16, Tokyo 184-8588, Japan.
Dev Comp Immunol. 2009 Jun;33(6):789-800. doi: 10.1016/j.dci.2009.01.005. Epub 2009 Feb 6.
C-type lectins can act as pattern recognition receptors (PRRs) in innate immunity. Previously, we identified two C-type lectins from silkworm (Bombyx mori), BmLBP and BmMBP, as PRRs. In the present study, we identified three homologs of these lectins by searching the silkworm genome database. These novel B. mori low-expression lectins were designated BmLEL-1, BmLEL-2, and BmLEL-3. Although Western-blot analysis failed to detect BmLEL-1, -2, or -3 in plasma, affinity precipitation of larval plasma with various microorganisms revealed that BmLEL-1 and -2 bind to rough and smooth strains of Gram-negative bacteria, respectively. BmLEL-1, -2, and -3 were found to be expressed in testis and ovary, where BmLEL-2 expression was up-regulated after bacteria infection. These results indicate that the novel C-type lectins might play a role in the innate immunity in these tissues as PRRs. Here, we discuss the roles and members of the C-type lectins as primary PRRs in B. mori cellular immunity.
C型凝集素可作为天然免疫中的模式识别受体（PRR）。此前，我们从家蚕（Bombyx mori）中鉴定出两种C型凝集素，即BmLBP和BmMBP，作为PRR。在本研究中，我们通过搜索家蚕基因组数据库鉴定出了这些凝集素的三个同源物。这些新型家蚕低表达凝集素被命名为BmLEL-1、BmLEL-2和BmLEL-3。尽管蛋白质免疫印迹分析未能在血浆中检测到BmLEL-1、-2或-3，但用各种微生物对幼虫血浆进行亲和沉淀显示，BmLEL-1和-2分别与革兰氏阴性菌的粗糙型和光滑型菌株结合。发现BmLEL-1、-2和-3在睾丸和卵巢中表达，其中细菌感染后BmLEL-2的表达上调。这些结果表明，新型C型凝集素可能作为PRR在这些组织的天然免疫中发挥作用。在此，我们讨论了C型凝集素作为家蚕细胞免疫中主要PRR的作用和成员。
