SummaryProtein homology studies identified five kinases potentially capable of phosphorylating the Spo0F response regulator and initiating sporulation in Bacillus subtilis. Two of these kinases, KinA and KinB, were known from previous studies to be responsible for sporulation in laboratory media. In vivo studies of the activity of four of the kinases, KinA, KinC, KinD (ykvD) and KinE (ykrQ), using abrB transcription as an indicator of Spo0A,P level, revealed that KinC and KinD were responsible for Spo0A,P production during the exponential phase of growth in the absence of KinA and KinB. In vitro, all four kinases dephosphorylated Spo0F,P with the production of ATP at approximately the same rate, indicating that they possess approximately equal affinity for Spo0F. All the kinases were expressed during growth and early stationary phase, suggesting that the differential activity observed in growth and sporulation results from differential activation by signal ligands unique to each kinase.

In this open-label randomized clinical trial, HLA-identical sibling-matched hematopoietic stem cells (HSC) were transplanted (non-MSCs group, n ¼ 15) or cotransplanted with mesenchymal stem cells (MSCs) (MSCs group, n ¼ 10) in hematologic malignancy patients. The median number of MSCs infused was 3.4 Â 10 5 kg À1 (range, 0.3-15.3 Â 10 5 kg À1 ). MSCs infusions were well tolerated. The median time to neutrophil engraftment (absolute neutrophil count 40.5 Â 10 9 l À1 ) was 16 days for MSCs group and 15 days for non-MSCs group. The median time to platelet engraftment (platelet count 450 Â 10 9 l À1 ) was 30 and 27 days, respectively. Grades II-IV acute graft-versus-host disease (GVHD) was observed respectively, in one (11.1%) and eight (53.3%) evaluable patients. Chronic GVHD was found in one (14.3%) and four (28.6%) evaluable patients. The number of patients who relapsed were six (60.0%) and three (20.0%), and the 3-year disease-free survivals were 30.0 and 66.7%, respectively. Thus cotransplantation of MSCs and HSCs may prevent GVHD, but the relapse rate is obviously higher than the control group. We conclude that use of MSCs must be handled with extreme caution before a large-scale clinical trial is performed.

We recently reported the discovery of AM-8553 (1), a potent and selective piperidinone inhibitor of the MDM2-p53 interaction. Continued research investigation of the N-alkyl substituent of this series, focused in particular on a previously underutilized interaction in a shallow cleft on the MDM2 surface, led to the discovery of a one-carbon tethered sulfone which gave rise to substantial improvements in biochemical and cellular potency. Further investigation produced AMG 232 (2), which is currently being evaluated in human clinical trials for the treatment of cancer. Compound 2 is an extremely potent MDM2 inhibitor (SPR KD = 0.045 nM, SJSA-1 EdU IC50 = 9.1 nM), with remarkable pharmacokinetic properties and in vivo antitumor activity in the SJSA-1 osteosarcoma xenograft model (ED50 = 9.1 mg/kg).

We have previously shown that Toll-like receptor (TLR)-activated murine nonparenchymal liver cells [(NPC); Kupffer cells (KC), liver sinusoidal endothelial cells (LSEC)]T he hepatitis B virus (HBV) is a hepatotropic DNA virus that can lead to chronic hepatitis, which can be complicated by the development of liver cirrhosis and hepatocellular carcinoma. Current approved therapeutic strategies for treatment HBV include interferon-alpha (IFN-␣) and nucleoside and nucleotide analogs. 1,2 However, only a minority of patients that are treated with these agents show a long-term sustained response with "eradication" [for example, hepatitis B surface antigen (HBsAg) loss] of the virus.

Summary Little is known of how the Toll‐like receptor (TLR) system can modulate the function of non‐parenchymal liver cells (NPC) as a major component of the innate and adaptive immune system of the liver. To investigate the diversification of TLR signalling pathways in NPC, we isolated Kupffer cells (KC) and liver sinusoidal endothelial cells (LSEC) from wild‐type C57BL/6 mice and examined their responses to TLR1 to TLR9 agonists. The data show that KC respond to all TLR ligands by producing tumour necrosis factor‐α (TNF‐α) or interleukin‐6 (IL‐6), to TLR3 and TLR4 ligands only by producing interferon‐β (IFN‐β), to TLR1 and TLR8 ligands by significantly up‐regulating major histocompatibility complex (MHC) class II and costimulatory molecules, and to TLR1, ‐2, ‐4 and ‐6 ligands by inducing high levels of T‐cell proliferation and IFN‐γ production in the mixed lymphocyte reaction (MLR). Similarly, LSEC respond to TLR1 to ‐4, ‐6, ‐8 and ‐9 ligands by producing TNF‐α, to TLR3 and ‐4 ligands by producing IL‐6, and to TLR3 ligands by producing IFN‐β. Interestingly, despite significant up‐regulation of MHC class II and co‐stimulatory molecules in response to TLR8 ligands, LSEC stimulated by TLR1, ‐2 or ‐6 could stimulate allogeneic T cells as assessed by MLR. By contrast, myeloid dendritic cells, used as positive control for classical antigen‐presenting cells, respond to TLR1, ‐2, ‐4 and ‐9 ligands by both up‐regulation of CD40 and activation of allogeneic T cells. In conclusion, NPC display a restricted TLR‐mediated activation profile when compared with ‘classical’ antigen‐presenting cells which may, at least in part, explain their tolerogenic function in the liver.