Activation of mitogen activated protein kinases via complement receptor type 2

Background Complement receptor type 2 (CR2) is the receptor for C3d and C3dg and for Epstein Barr virus The aim of our study was to explore whether CR2 can independently mediate the activation of mitogen activated protein kinases (MAPKs, including ERK, JNK, and p38MAPK), and to highlight the molecular mechanism of CD 4 + cell deletion in AIDS Methods HOS cells (HOS CR2) and HOS CD4 cells (HOS CD4CR2) stably expressing CR2 were established and then identified by FACS and Western blotting Activation and blocking tests of MAPKs were assessed by Western blot Cell proliferation was determined using Cell Titer 96 Aqueous One Solution Reagent Results FACS results showed that the positive rates of HOS CR2 and HOS CD4CR2 cells were greater than 96%, and Western blot showed that the CR2 expression levels on HOS CR2 and HOS CD4CR2 cells were high Activation and blocking tests of MAPKs (ERK, JNK, and p38MAPK) were carried out in HOS CR2, HOS CD4, and HOS CD4CR2 cells The activation of MAPKs in HOS CR2 cells stimulated with PMA (100 ng/ml) and NHS (10%) was identical The activation of MAPKs increased at 5 minutes, reached a peak at 10 minutes, and decreased to baseline within 30 minutes, all in a time dependent manner; the activation of MAPKs was blocked by anti CR2 McAb, PD98059 (inhibitor of ERK), and Wortmanin (inhibitor of PI 3K), respectively In HOS CD4 cells, MAPKs were activated by HIV gp160 In HOS CD4CR2 cells, MAPK activation was induced by HIV gp160, 10% NHS, and HIV gp160+10%NHS; phosphorylation of p38MAPK was dramatically induced by HIV gp160+NHS, and lasted for 1 hour The cell proliferation results showed that HIV gp160 inhibited the proliferation of HOS CD4 and HOS CD4CR2 cells ( P <0 01) and that NHS enhanced the effect of HIV gp160 ( P <0 01) Conclusions The activation of MAPKs is independently mediated by CR2 and that anti CR2 McAb, PD98059, and Wortmanin block the activation of MAPKs, respectively The results of the signal transduction and cell proliferation assays of HOS CD4CR2 cells show that CR2 plays a role in the pathogenesis of HIV infection, especially in the inhibition of CD 4 + cell proliferation

Proposed nomenclature for Pseudallescheria,Scedosporium and related genera

As a result of fundamental changes in the International Code of Nomenclature on the use of separate names for sexual and asexual stages of fungi,generic names of many groups should be reconsidered.Members of the ECMM/ISHAM working group on Pseudallescheria/Scedosporium infections herein advocate a novel nomenclature for genera and species in Pseudallescheria,Scedosporium and allied taxa.The generic names Parascedosporium,Lomentospora,Petriella,Petriellopsis,and Scedosporium are proposed for a lineage within Microascaceae with mostly Scedosporium anamorphs producing slimy,annellidic conidia.Considering that Scedosporium has priority over Pseudallescheria and that Scedosporium prolificans is phylogenetically distinct from the other Scedosporium species,some name changes are proposed.Pseudallescheria minutispora and Petriellidium desertorum are renamed as Scedosporium minutisporum and S.desertorum,respectively.Scedosporium prolificans is renamed as Lomentospora prolificans.