ABSTRACT
Embryo is regarded as a semi-allograft for carrying paternal genetic information. It can escape the attack from maternal immune system and successfully implant into the uterus, which mainly relies on the establishment of immune tolerance at the maternal-fetal interface. The maternal-fetal interface is the basis for the connection and material exchange between the mother and fetus. The mechanisms of immune re-sponses at this interface are the key to the maintenance of normal pregnancy. Immunomodulatory molecules expressed at the maternal-fetal interface are vital for immune tolerance. Studies have shown that sialicacid-binding immunoglobulin-like lectins (Siglecs) are abundantly expressed at the maternal-fetal interface and play an important role in immune regulation. Siglecs are important members of the typeⅠimmunoglobulin-like superfamily. By binding with the sialic acid residues on the side chains of glycoproteins or glycolipids, Siglecs involve in immune regulation, the activation and proliferation of immune cells and immune cell-medi-ated physiological and pathological processes. Present research on the expression of Siglecs in the maternal-fetal interface is mainly focused on Siglec-6 and Siglec-10, while other Siglecs are less studied. Siglecs, such as Siglec-6 and Siglec-10, might involve in the regulation of immune tolerance at the maternal-fetal in-terface through binding to different ligands. This article briefly reviewed the expression of Siglecs and their ligands at the maternal-fetal interface and their roles in immune tolerance.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the species and distribution of mosquitoes and mosquito-borne arboviruses in Yuncheng city of Shanxi province, China.</p><p><b>METHODS</b>Mosquito samples were collected in 19 collection sites from Linyi county and Yongji city in Yuncheng city, in August, 2012. After identification and classification, all the specimens were homogenized and centrifuged to acquire supernatant before being inoculated to both C6/36 and BHK21 cells for viral isolation. Positive isolates were identified with arbovirus species-specific primers under RT-PCR, for further sequencing and phylogenetic analysis.</p><p><b>RESULTS</b>A total of 10 455 mosquitoes of 7 species in 4 genuese were collected. The predominant mosquito species in Linyi county was Culex pipens pallens (91.96%, 3 911/4 253), but the one in Yongji city was Culex tritaeniorhynchus (72.85%, 4 518/6 202). A total of 23 strains of viruses were isolated from the mosquito pools. 15 strains from Culex tritaeniorhynchus and Culex pipens pallens were identified as genotype I Japanese encephalitis virus (JEV). Four strains from Culex pipens pallens were identified as Culex flavivirus (CxFV). Three strains from Culex pipens pallens were identified as Culex pipiens pallens densovirus (CppDNV). One strain from Armigeres subalbatus and Aedes albopictus was identified as Getah virus (GETV).</p><p><b>CONCLUSION</b>Four kinds of arboviruses were isolated from the mosquito pools, including GETV and CxFV, which were isolated and documented in Shanxi province for the first time. In the city of Yuncheng, Culex tritaeniorhynchus had been the predominant species and major vector for transmitting JEV. Genotype I JEV remained the major JEV circulating in the local natural environment.</p>