Long-term effects: Galectin-1 and specific immunotherapy for allergic responses in the intestine.

BACKGROUND AND AIMS: Mast cell activation interferes with the effects of allergen-specific immunotherapy (SIT). Galectin-1 (Gal-1) is capable of regulating immune cells' functions. This study tests the hypothesis that administration of Gal-1 promotes and prolongs the efficacy of SIT via suppressing mast cell activation. METHODS: An intestinal allergy mouse model was developed. The coadministration of SIT and Gal-1 on suppression of the allergic responses, prevention of mast cell activation, and generation of antigen-specific regulatory T cells (Treg) in the intestine was observed in sensitized mice. RESULTS: The coadministration of Gal-1 and SIT markedly suppressed the allergic responses in the mouse intestine vs the use of either SIT alone or Gal-1 alone. The Gal-1 binds to the IgE/FcɛRI complexes on the surface of mast cells to prevent mast cell activation during SIT. Gal-1 promoted the SIT-generated allergen-specific Tregs in the intestine of sensitized mice. Coadministration of Gal-1 and SIT significantly enhanced the efficacy of immunotherapy in suppressing allergic responses in the intestine, which lasted for at least for 12 months. CONCLUSIONS: Long-term effects of specific immunotherapy on intestinal allergy can be achieved with Gal-1/SIT therapy by inhibiting mast cell activation and facilitating Treg development.

Forkhead box protein-3 (Foxp3)-producing dendritic cells suppress allergic response.

BACKGROUND: The generation of the tolerogenic dendritic cells (DC) is not fully understood yet. Forkhead box protein-3 (Foxp3) is an important molecule in the immune tolerance. This study tests a hypothesis that DCs express Foxp3, which can be upregulated by Staphylococcal enterotoxin B (SEB). METHODS: The expression of Foxp3 by DCs was evaluated by real-time RT-PCR, Western blotting, flow cytometry, and chromatin immunoprecipitation assay. RESULTS: We observed that mice treated with SEB at 0.25-0.5 µg/mouse showed high frequencies of transforming growth factor (TGF)-ß-producing CD4+ T cells and TGF-ß-producing DCs in the intestine, while the IL-4+ CD4+ T cells and TIM4+ DCs were dominated in the intestine in mice treated with SEB at 1-10 µg/mouse. Treating DCs with SEB in the culture induced high levels of Foxp3 at the TGF-ß promoter locus. The function of Foxp3 was blocked by STAT6 (signal transducer and activator transcription-6); the latter was induced by exposing DCs to SEB in the culture at doses of 100-400 ng/ml. Treating allergic mice with specific immunotherapy (SIT) together with SEB significantly promoted the therapeutic effects on the allergic responses than treating with SIT alone. CONCLUSION: Dendritic cells have the capacity to express Foxp3, which can be upregulated by exposure to SEB.

Characterization of cold-induced remodelling reveals depot-specific differences across and within brown and white adipose tissues in mice.

AIM: Brown and beige adipose tissues dissipate energy in the form of heat via mitochondrial uncoupling protein 1, defending against hypothermia and potentially obesity. The latter has prompted renewed interest in understanding the processes involved in browning to realize the potential therapeutic benefits. To characterize the temporal profile of cold-induced changes and browning of brown and white adipose tissues in mice. METHODS: Male C57BL/6J mice were singly housed in conventional cages under cold exposure (4 °C) for 1, 2, 3, 4, 5 and 7 days. Food intake and body weight were measured daily. Interscapular brown adipose tissue (iBAT), inguinal subcutaneous (sWAT) and epididymal white adipose tissue (eWAT) were harvested for histological, immunohistochemical, gene and protein expression analysis. RESULTS: Upon cold exposure, food intake increased, whilst body weight and adipocyte size were found to be transiently reduced. iBAT mass was found to be increased, whilst sWAT and eWAT were found to be transiently decreased. A combination of morphological, genetic (Ucp-1, Pgc-1α and Elov13) and biochemical (UCP-1, PPARγ and aP2) analyses demonstrated the depot-specific remodelling in response to cold exposure. CONCLUSION: Our results demonstrate the differential responses to cold-induced changes across discrete BAT and WAT depots and support the notion that the effects of short-term cold exposure are achieved by expansion, activation and increasing thermogenic capacity of iBAT, as well as browning of sWAT and, to a lesser extent, eWAT.

Pharmacokinetics studies of enrofloxacin injectable in situ forming gel in dogs.

The objective of this study was to evaluate the pharmacokinetic characteristics of enrofloxacin (ENR) injectable in situ gel we developed in dogs following a single intramuscular (i.m.) administration. Twelve healthy dogs were randomly divided into two groups (six dogs per group), then administrated a single 20 mg/kg body weight (b.w.) ENR injectable in situ gel and a single 5 mg/kg b.w. ENR conventional injection, respectively. High-performance liquid chromatography (HPLC) was used to determine ENR plasma concentrations. The pharmacokinetic parameters of ENR injectable in situ gel and conventional injection in dogs are as follows: MRT (mean residence time) (45.59 ± 14.05) h verse (11.40 ± 1.64) h, AUC (area under the blood concentration vs. time curve) (28.66 ± 15.41) µg·h/mL verse (11.06 ± 3.90) µg·h/mL, cmax (maximal concentration) (1.59 ± 0.35) µg/mL verse (1.46 ± 0.07) µg/mL, tmax (time needed to reach cmax ) (1.25 ± 1.37) h verse (1.40 ± 0.55) h, t1/2λz (terminal elimination half-life) (40.27 ± 17.79) h verse (10.32 ± 0.97) h. The results demonstrated that the in situ forming gel system could increase dosing interval of ENR and thus reduced dosing frequency during long-term treatment. Therefore, the ENR injectable in situ gel seems to be worth popularizing in veterinary clinical application.

MicroRNA-100/99a, deregulated in acute lymphoblastic leukaemia, suppress proliferation and promote apoptosis by regulating the FKBP51 and IGF1R/mTOR signalling pathways.

BACKGROUND: MicroRNAs alter multiple cell processes and thus influence tumour carcinogenesis and progression. MiR-100 and miR-99a have been reported to be aberrantly expressed in acute leukaemia. In this study, we focused on their functions in acute lymphoblastic leukaemia (ALL) and the molecular networks in which they are involved. METHODS: MiR-100 and miR-99a expression levels were measured in acute leukaemia patients by qRT-PCR. Kaplan-Meier analysis and log-rank tests were used to calculate the survival rate. Three human ALL cell lines were studied. Apoptosis and proliferation were analysed using siRNA transfection, western blot and flow cytometry. RESULTS: In vivo, miR-100 and miR-99a were down-regulated in 111 ALL patients, especially in high-risk groups; their expression levels were correlated with the patient's 5-year survival. In vitro, the restoration of miR-100 and miR-99a in ALL cells suppressed cell proliferation and increased dexamethasone-induced cell apoptosis. Ectopic expression of miR-100 and miR-99a targeted FK506-binding protein 51 (FKBP51) and, in turn, influenced glucocorticoid receptor (GR) activity. Meanwhile, miR-100 and miR-99a overexpression inhibited the expression of IGF1R and mTOR and their downstream oncogene MCL1. CONCLUSION: MiR-100 and miR-99a have critical roles in altering cellular processes by targeting both the FKBP51 and IGF1R/mTOR signalling pathways in vitro and might represent a potential novel strategy for ALL treatment.

MiR-100 regulates cell differentiation and survival by targeting RBSP3, a phosphatase-like tumor suppressor in acute myeloid leukemia.

Acute myeloblastic leukemia (AML) is characterized by the accumulation of abnormal myeloblasts (mainly granulocyte or monocyte precursors) in the bone marrow and blood. Though great progress has been made for improvement in clinical treatment during the past decades, only minority with AML achieve long-term survival. Therefore, further understanding mechanisms of leukemogenesis and exploring novel therapeutic strategies are still crucial for improving disease outcome. MicroRNA-100 (miR-100), a small non-coding RNA molecule, has been reported as a frequent event aberrantly expressed in patients with AML; however, the molecular basis for this phenotype and the statuses of its downstream targets have not yet been elucidated. In the present study, we found that the expression level of miR-100 in vivo was related to the stage of the maturation block underlying the subtypes of myeloid leukemia. In vitro experiments further demonstrated that miR-100 was required to promote the cell proliferation of promyelocytic blasts and arrest them differentiated to granulocyte/monocyte lineages. Significantly, we identified RBSP3, a phosphatase-like tumor suppressor, as a bona fide target of miR-100 and validated that RBSP3 was involved in cell differentiation and survival in AML. Moreover, we revealed a new pathway that miR-100 regulates G1/S transition and S-phase entry and blocks the terminal differentiation by targeting RBSP3, which partly in turn modulates the cell cycle effectors pRB/E2F1 in AML. These events promoted cell proliferation and blocked granulocyte/monocyte differentiation. Our data highlight an important role of miR-100 in the molecular etiology of AML, and implicate the potential application of miR-100 in cancer therapy.

Cutaneous adverse drug reactions in a hospital-based Chinese population.

BACKGROUND: Cutaneous adverse drug reactions (CADRs) are common skin adverse reactions associated with drugs. AIM: To assess recent trends in CADRs and the drugs associated with them, using data from the past 5 years in the largest single database available on a hospital-based population in China. METHODS: All clinical records of inpatients admitted with a diagnosis of CADR to the Dermatology Ward, Huashan Hospital from January 2004 to December 2008 were retrospectively studied. RESULTS: In the 734 patients, the three most common types of CADRs were nonsevere reactions, erythema multiforme (EM)-like eruptions (n = 255), urticaria (n = 192) and exanthematous reactions (n = 159), followed by three severe reactions: Stevens-Johnson syndrome (n = 58), toxic epidermal necrolysis (n = 29) and exfoliative dermatitis (n = 22). The most common single drug associated with the development of all drug eruptions was allopurinol, followed by amoxicillin, cephalosporins, antiepileptic agents and antipyretic/analgesic agents. However, the most common single drugs associated with severe reactions were antiepileptic agents, followed by allopurinol, antipyretic/analgesic agents and cephalosporins. In contrast to patients with nonsevere reactions, patients with severe reactions were more likely to be male (P < 0.001) and to have a greater mean age of onset (P < 0.001), a longer latency period (P < 0.001) and a longer duration of hospitalization (P < 0.001). CONCLUSION: In contrast to previous studies, we found allopurinol to be the most common single drug associated with CADRs followed by antibiotics (amoxicillin and cephalosporins), and antiepileptic, especially carbamazepine. A higher incidence of EM-like eruptions and urticaria was also seen.