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Fibroblastic reticular cells (FRCs), a subpopulation of stromal cells in lymphoid organs and fat-associated lymphoid clusters (FALCs) in adipose tissue, play immune-regulatory roles in the host response to infection and may be useful as a form of cell therapy in sepsis. Here, we found an unexpected major role of TLR9 in controlling peritoneal immune cell recruitment and FALC formation at baseline and after sepsis induced by cecal ligation and puncture (CLP). TLR9 regulated peritoneal immunity via suppression of chemokine production by FRCs. Adoptive transfer of TLR9- deficient FRCs more effectively decreased mortality, bacterial load, and systemic inflammation after CLP than WT FRCs. Importantly, we found that activation of TLR9 signaling suppressed chemokine production by human adipose tissue-derived FRCs. Together, our results indicate that TLR9 plays critical roles in regulating peritoneal immunity via suppression of chemokine production by FRCs. These data form a knowledge basis upon which to design new therapeutic strategies to improve the therapeutic efficacy of FRC-based treatments for sepsis and immune dysregulation diseases., Introduction Sepsis is now the leading cause of death in US hospitals and is projected to account for more than 5 million deaths globally each year (1-3). Currently, no effective [...]

The electrochemical deposition and dissolution of lead on gold electrodes immersed in an aqueous solution of lead nitrate were studied in situ using a biasing liquid cell by transmission electron microscopy (TEM). We investigate in real time the growth mechanisms of lead dendrites as deposited on the electrodes under an applied potential. TEM images reveal that lead dendrites are developed by the fast protrusion of lead branches in the electrolyte and tip splitting. And, the fast growing tip of the dendritic branch is composed of polycrystalline nanograins and it develops into a single crystalline branch eventually. This study demonstrated unique electrochemical growth of single crystal dendrites through nucleation, aggregation, alignment and attachment of randomly oriented small grains. Additionally, we found the lead concentration in the electrolyte drastically influences the morphology of dendritic formation.

Phosphorus (P) deficiency is one of the limiting factors in crop production. Large genetic variations in crop P efficiency have been evaluated, and thus their genetic improvement should be important to address this problem. However, 50–80% of the total P in agricultural soils exists as organic compounds. One strategy for improving crop P nutrition is to enhance root secretion of acid phosphatases (APases) to obtain or remobilize Pi from organic P sources. Purple acid phosphatase (PAP) is a special group of APase with distinct properties. However, the molecular properties and functions of PAPs have not been well studied. In the present study, we found that there are four PvPAPs in common bean, which contain five blocks of conserved amino acid motifs with seven invariant residues. Subsequently, functions of P starvation-induced PvPAP3 were elucidated. Phylogenetic analysis shows that PvPAP1 and PvPAP2, PvPAP3 and PvPAP4 separately belong to high and low molecular mass PAP groups. Expression patterns of the four PvPAPs are obviously different as related to Pi availability. Among them, strong induced expression of PvPAP3 was detected by Pi starvation in roots. Transgenic Arabidopsis plants overexpressing PvPAP3 have superior growth and P uptake when ATP was supplied as the sole external P source. Taken together, our study demonstrated that the P efficiency in common bean could be improved through overexpression of PvPAP3, thus might have great implications for improving crop production on soils lacking of available P which is a serious limitation worldwide.