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Chemokine receptors transduce signals important for the function and trafficking of leukocytes. Recently, it has been shown that CC chemokine receptor (CCR)8 is selectively expressed by Th2 subsets, but its functional relevance is unclear. To address the biological role of CCR8, we generated CCR8 deficient (-/-) mice. Here we report defective T helper type 2 (Th2) immune responses in vivo in CCR8(-/)- mice in models of Schistosoma mansoni soluble egg antigen (SEA)-induced granuloma formation as well as ovalbumin (OVA)- and cockroach antigen (CRA)-induced allergic airway inflammation. In these mice, the response to SEA, OVA, and CRA showed impaired Th2 cytokine production that was associated with aberrant type 2 inflammation displaying a 50 to 80% reduction in eosinophils. In contrast, a prototypical Th1 immune response, elicited by Mycobacteria bovis purified protein derivative (PPD) was unaffected by CCR8 deficiency. Mechanistic analyses indicated that Th2 cells developed normally and that the reduction in eosinophil recruitment was likely due to systemic reduction in interleukin 5. These results indicate an important role for CCR8 in Th2 functional responses in vivo.

6Ckine is an unusual chemokine capable of attracting naive T lymphocytes in vitro. It has been recently reported that lack of 6Ckine expression in lymphoid organs is a prominent characteristic of mice homozygous for the paucity of lymph node T cell (plt) mutation. These mice show reduced numbers of T cells in lymph nodes, Peyer's patches, and the white pulp of the spleen. The genetic reason for the lack of 6Ckine expression in the plt mouse, however, has remained unknown. Here we demonstrate that mouse 6Ckine is encoded by two genes, one of which is expressed in lymphoid organs and is deleted in plt mice. A second 6Ckine gene is intact and expressed in the plt mouse.

Background: Prophylactic human papillomavirus (HPV) vaccines have to provide sustained protection. We assessed efficacy, immunogenicity, and safety of the HPV-16/18 AS04-adjuvanted vaccine up to 6.4 years.Methods: Women aged 15-25 years, with normal cervical cytology, who were HPV-16/18 seronegative and oncogenic HPV DNA-negative (14 types) at screening participated in a double-blind, randomised, placebo-controlled initial study (n=1113; 560 vaccine group vs 553 placebo group) and follow-up study (n=776; 393 vs 383). 27 sites in three countries participated in the follow-up study. Cervical samples were tested every 6 months for HPV DNA. Management of abnormal cytologies was prespecified, and HPV-16/18 antibody titres were assessed. The primary objective was to assess long-term vaccine efficacy in the prevention of incident cervical infection with HPV 16 or HPV 18, or both. We report the analyses up to 6.4 years of this follow-up study and combined with the initial study. For the primary endpoint, the efficacy analysis was done in the according-to-protocol (ATP) cohort; the analysis of cervical intraepithelial neoplasia grade 2 and above (CIN2+) was done in the total vaccinated cohort (TVC). The study is registered with ClinicalTrials.gov, number NCT00120848.Findings: For the combined analysis of the initial and follow-up studies, the ATP efficacy cohort included 465 women in the vaccine group and 454 in the placebo group; the TVC included 560 women in the vaccine group and 553 in the placebo group. Vaccine efficacy against incident infection with HPV 16/18 was 95.3% (95% CI 87.4-98.7) and against 12-month persistent infection was 100% (81.8-100). Vaccine efficacy against CIN2+ was 100% (51.3-100) for lesions associated with HPV-16/18 and 71.9% (20.6-91.9) for lesions independent of HPV DNA. Antibody concentrations by ELISA remained 12-fold or more higher than after natural infection (both antigens). Safety outcomes were similar between groups: during the follow-up study, 30 (8%) participants reported a serious adverse event in the vaccine group versus 37 (10%) in the placebo group. None was judged related or possibly related to vaccination, and no deaths occurred.Interpretation: Our findings show excellent long-term efficacy, high and sustained immunogenicity, and favourable safety of the HPV-16/18 AS04-adjuvanted vaccine up to 6.4 years.Funding: GlaxoSmithKline Biologicals (Belgium). [ABSTRACT FROM AUTHOR]

Background: The aim of this interim analysis of a large, international phase III study was to assess the efficacy of an AS04 adjuvanted L1 virus-like-particle prophylactic candidate vaccine against infection with human papillomavirus (HPV) types 16 and 18 in young women.Methods: 18,644 women aged 15-25 years were randomly assigned to receive either HPV16/18 vaccine (n=9319) or hepatitis A vaccine (n=9325) at 0, 1, and 6 months. Of these women, 88 were excluded because of high-grade cytology and 31 for missing cytology results. Thus, 9258 women received the HPV16/18 vaccine and 9267 received the control vaccine in the total vaccinated cohort for efficacy, which included women who had prevalent oncogenic HPV infections, often with several HPV types, as well as low-grade cytological abnormalities at study entry and who received at least one vaccine dose. We assessed cervical cytology and subsequent biopsy for 14 oncogenic HPV types by PCR. The primary endpoint--vaccine efficacy against cervical intraepithelial neoplasia (CIN) 2+ associated with HPV16 or HPV18--was assessed in women who were seronegative and DNA negative for the corresponding vaccine type at baseline (month 0) and allowed inclusion of lesions with several oncogenic HPV types. This interim event-defined analysis was triggered when at least 23 cases of CIN2+ with HPV16 or HPV18 DNA in the lesion were detected in the total vaccinated cohort for efficacy. Analyses were done on a modified intention-to-treat basis. This trial is registered with the US National Institutes of Health clinical trial registry, number NCT00122681.Findings: Mean length of follow-up for women in the primary analysis for efficacy at the time of the interim analysis was 14.8 (SD 4.9) months. Two cases of CIN2+ associated with HPV16 or HPV18 DNA were seen in the HPV16/18 vaccine group; 21 were recorded in the control group. Of the 23 cases, 14 (two in the HPV16/18 vaccine group, 12 in the control group) contained several oncogenic HPV types. Vaccine efficacy against CIN2+ containing HPV16/18 DNA was 90.4% (97.9% CI 53.4-99.3; p<0.0001). No clinically meaningful differences were noted in safety outcomes between the study groups.Interpretation: The adjuvanted HPV16/18 vaccine showed prophylactic efficacy against CIN2+ associated with HPV16 or HPV18 and thus could be used for cervical cancer prevention. [ABSTRACT FROM AUTHOR]

Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of insulin-producing β-cells in the pancreas. This destruction leads to chronic hyperglycemia, necessitating lifelong insulin therapy to manage blood glucose levels. Typically diagnosed in children and young adults, T1D can, however, occur at any age. Ongoing research aims to uncover the precise mechanisms underlying T1D and to develop potential interventions. These include efforts to modulate the immune system, regenerate β-cells, and create advanced insulin delivery systems. Emerging therapies, such as closed-loop insulin pumps, stem cell-derived β-cell replacement and disease-modifying therapies (DMTs), offer hope for improving the quality of life for individuals with T1D and potentially moving towards a cure. Currently, there are no disease-modifying therapies approved for stage 3 T1D. Preserving β-cell function in stage 3 T1D is associated with better clinical outcomes, including lower HbA1c and decreased risk of hypoglycemia, neuropathy, and retinopathy. Tumor Necrosis Factor alpha (TNF-α) inhibitors have demonstrated efficacy at preserving β-cell function by measurement of C-peptide in two clinical trials in people with stage 3 T1D. However, TNF-α inhibitors have yet to be evaluated in a pivotal trial for T1D. To address the promising clinical findings of TNF-α inhibitors in T1D, Breakthrough T1D convened a panel of key opinion leaders (KOLs) in the field. The workshop aimed to outline an optimal clinical path for moving TNF-α inhibitors to a pivotal clinical trial in T1D. Here, we summarize the evidence for the beneficial use of TNF-α inhibitors in T1D and considerations for strategies collectively identified to advance TNF-α inhibitors beyond phase 2 clinical studies for stage 3 T1D., Competing Interests: MAM is employed by the company Quaestio Global Partners, LLC. TM is employed by the company Putnam Associates. JM is employed by the company Medtronic. TQ is a consultant for Janssen Research & Development, Merck, SANOFI and Pfizer and a Clinical Trial, Principal Investigator at the Buffalo site: SANOFI, OPKO Biologics Ltd. Ascendis, Lumos and Pfizer. EL is a former employee of Regeneron Pharmaceuticals and owns company stock. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Bazile, Abdel Malik, Ackeifi, Anderson, Beck, Donath, Dutta, Hedrick, Karpen, Kay, Marder, Marinac, McVean, Meyer, Pettus, Quattrin, Verstegen, Vieth and Latres.)

Peptide loading of MHC class II (MHCII) molecules is facilitated by HLA-DM (DM), which catalyzes CLIP release, stabilizes empty MHCII, and edits the MHCII-bound peptide repertoire. HLA-DO (DO) binds to DM and modulates its activity, resulting in an altered set of peptides presented at the cell surface. MHCII-peptide presentation in individuals with type 1 diabetes (T1D) is abnormal, leading to a breakdown in tolerance; however, no direct measurement of the MHCII pathway activity in T1D patients has been performed. In this study, we measured MHCII Ag-processing pathway activity in humans by determining MHCII, MHCII-CLIP, DM, and DO levels by flow cytometry for peripheral blood B cells, dendritic cells, and monocytes from 99 T1D patients and 97 controls. Results showed that MHCII levels were similar for all three APC subsets. In contrast, MHCII-CLIP levels, independent of sex, age at blood draw, disease duration, and diagnosis age, were significantly increased for all three APCs, with B cells showing the largest increase (3.4-fold). DM and DO levels, which usually directly correlate with MHCII-CLIP levels, were unexpectedly identical in T1D patients and controls. Gene expression profiling on PBMC RNA showed that DMB mRNA was significantly elevated in T1D patients with residual C-peptide. This resulted in higher levels of DM protein in B cells and dendritic cells. DO levels were also increased, suggesting that the MHCII pathway maybe differentially regulated in individuals with residual C-peptide. Collectively, these studies show a dysregulation of the MHCII Ag-processing pathway in patients with T1D., (Copyright © 2023 by The American Association of Immunologists, Inc.)

Golimumab was recently evaluated in a phase 2a, randomized, double-blind, placebo-controlled, multicenter study (T1GER study) for safety and efficacy in children and young adults with newly diagnosed type 1 diabetes (T1D). Golimumab showed significant treatment effect where endogenous insulin production was preserved and clinical and metabolic parameters were improved. The objective of this report was to evaluate pharmacokinetic (PK) and pharmacodynamic data from the T1GER study by developing a population pharmacokinetic (PopPK) model and performing exposure-response (ER) analyses. The PopPK model was developed using data from the T1D study and 2 other pediatric studies with golimumab in ulcerative colitis and in polyarticular juvenile idiopathic arthritis. A 1-compartment model with first-order absorption and elimination was applied to describe the concentration-time profiles. Typical parameters normalized to the values in subjects with a standard weight of 70 kg were apparent clearance, 0.850 L/day; apparent volume of distribution, 16.0 L; and absorption rate constant, 1.01/day. From the ER analyses, no clear trends were observed for changes in both C-peptide area under the concentration-time curve and hemoglobin A 1c levels for the relatively narrow exposure ranges following the body surface area-based dosing regimen used in this study. In conclusion, the developed PopPK model was able to adequately describe the observed PK of golimumab in patients with T1D. Although golimumab showed significant treatment effect, the ER analyses did not show clear trends within the active treatment group, which may indicate that the exposure from this T1D-specific dosing regimen was at the plateau of the ER curve., (© 2023, The American College of Clinical Pharmacology.)

Objective: The T1GER (A Study of SIMPONI to Arrest β-Cell Loss in Type 1 Diabetes) study showed many metabolic benefits of the tumor necrosis factor-α blocker golimumab in children and young adults with type 1 diabetes (T1D). Off-therapy effects are reported., Research Designs and Methods: T1GER was a phase 2, placebo-controlled, randomized trial in which golimumab or placebo was administered for 52 weeks to participants 6-21 years old diagnosed with T1D within 100 days of randomization. Assessments occurred during the 52-week on-therapy and 52-week off-therapy periods., Results: After treatment was stopped, C-peptide area under the curve (AUC) remained greater in the treatment versus control group. At weeks 78 and 104, the golimumab group had lower reductions in the 4-h C-peptide AUC baseline than the placebo group, where specifically the golimumab group had reductions of 0.31 and 0.41 nmol/L, and the placebo group had reductions of 0.64 and 0.74 nmol/L. There were also trends in less insulin use, higher peak C-peptide levels and those in partial remission, and higher peak C-peptide levels in the golimumab group. Golimumab responders, defined as having an increase or minimal loss of C-peptide AUC and/or being in partial remission at week 52, showed even greater improvements in most metabolic parameters on and off therapy and had less hypoglycemia during the off-therapy period versus placebo. Adverse events, including infections, were similar between the groups during all time periods of the study., Conclusions: In children and young adults with new-onset T1D, golimumab preserved endogenous β-cell function and resulted in other favorable metabolic parameters on and off therapy. A subpopulation had disease stabilization while on therapy, with improved metabolic parameters off therapy., (© 2023 by the American Diabetes Association.)

Importance: Ciprofloxacin, 0.3%, plus fluocinolone acetonide, 0.025%, otic solution seems to be efficacious and safe in treating acute otitis externa (AOE) compared with ciprofloxacin, 0.3%, or fluocinolone acetonide, 0.025%, otic solution alone., Objective: To evaluate the superiority of ciprofloxacin, 0.3%, plus fluocinolone acetonide, 0.025%, otic solution compared with ciprofloxacin, 0.3%, or fluocinolone acetonide, 0.025%, otic solution alone in treating AOE., Design, Setting, and Participants: A phase 3 randomized, double-blind, active-controlled clinical trial was conducted between August 1, 2017, and September 14, 2018, at 36 centers in the US. The study population comprised 493 patients aged 6 months or older with AOE of less than 21 days' duration with otorrhea, moderate or severe otalgia, and edema, as well as a Brighton grading of II or III (tympanic membrane obscure but without systemic illness). Statistical analysis was performed from November 14, 2018, to February 14, 2019., Interventions: Participants were randomly assigned to receive ciprofloxacin plus fluocinolone, ciprofloxacin, or fluocinolone twice daily for 7 days and were evaluated on day 1 (visit 1; baseline), days 3 to 4 (visit 2; conducted via telephone), days 8 to 10 (visit 3; end of treatment), and days 15 to 17 (visit 4; test of cure)., Main Outcomes and Measures: The primary outcome was therapeutic cure (clinical and microbiological) at the end of the treatment period. The principal secondary end point was the time to end of ear pain. Efficacy analyses were conducted in the microbiological intent-to-treat population, clinical intent-to-treat population, and microbiological intent-to-treat population with Pseudomonas aeruginosa and Staphylococcus aureus., Results: A total of 493 patients (254 female patients [51.5%]; mean [SD] age, 38.2 [23.1] years) were randomized (197 to receive ciprofloxacin plus fluocinolone, 196 to receive ciprofloxacin, and 100 to receive fluocinolone). Therapeutic cure in the modified intent-to-treat population with ciprofloxacin plus fluocinolone (63 of 103 [61.2%]) was statistically comparable to that of ciprofloxacin (49 of 91 [53.8%]; difference in response rate, 7.3%; 95% CI, -6.6% to 21.2%; P = .30) and fluocinolone (20 of 45 [44.4%]; difference in response rate, 16.7%; 95% CI, -0.6% to 34.0%; P = .06) at visit 3 and significantly superior to ciprofloxacin at visit 4 (90 of 103 [87.4%] vs 69 of 91 [75.8%]; difference in response rate, 11.6%; 95% CI, 0.7%-22.4%; P = .04). A statistically faster resolution of otalgia was achieved among patients treated with ciprofloxacin plus fluocinolone (median, 5.0 days [range, 4.2-6.3 days]) vs ciprofloxacin (median, 5.9 days [range, 4.3-7.3 days]; 95% CI, 4.3-7.3 days; P = .002) or fluocinolone (median, 7.7 days [range, 6.7-9.0 days]; 95% CI, 6.7-9.0 days; P < .001). Ciprofloxacin plus fluocinolone demonstrated statistical superiority in sustained microbiological response vs ciprofloxacin (94 of 103 [91.3%] vs 74 of 91 [81.3%]; difference in response rate, 9.9%; 95% CI, 0.3%-19.6%; P = .04) and fluocinolone (34 of 45 [75.6%]; difference in response rate, 15.7%; 95% CI, 2.0%-29.4%; P = .01) and in the microbiological outcome vs fluocinolone by visit 3 (99 of 103 [96.1%] vs 37 of 45 [82.2%]; difference in response rate, 13.9%; 95% CI, 2.1%-25.7%; P = .01) and ciprofloxacin by visit 4 (97 of 103 [94.2%] vs 77 of 91 [84.6%]; difference in response rate, 9.6%; 95% CI, 0.9%-18.2%; P = .02). Fifteen adverse events related to study medications were registered, all of which were mild or moderate., Conclusions and Relevance: Ciprofloxacin, 0.3%, plus fluocinolone acetonide, 0.025%, otic solution was efficacious and safe in treating AOE but did not demonstrate superiority vs ciprofloxacin, 0.3%, or fluocinolone acetonide, 0.025%, otic solutions alone in the main study end point of therapeutic cure., Trial Registration: ClinicalTrials.gov Identifier: NCT03196973.

Background: The MenACYW-TT conjugate vaccine is approved for prevention of invasive meningococcal disease (IMD) as a single dose in individuals ≥2 years of age in the United States and ≥12 months in EU and some other countries. This Phase II study evaluated the safety and immunogenicity of this vaccine and of concomitant pediatric vaccines in infants/toddlers (6 weeks-15 months of age)., Methods: Five schedules of the MenACYW-TT conjugate vaccine were evaluated in the United States: 2, 4, 6, and 12 months; 2, 4, 6, and 15 months; 2, 4, and 12 months; 6 and 12 months; and 12 months alone. Routine pediatric vaccines (DTaP-IPV/Hib, PCV7/PCV13, MMR, and varicella) were administered per approved schedules. Proportions of participants with serum bactericidal antibodyassay with human complement (hSBA) titers ≥1:4 and ≥1:8, SBA with baby rabbit complement (rSBA) titers ≥1:8 and ≥1:128, and immune responses against concomitant vaccines were determined., Results: Tenderness and irritability were the most frequent solicited injection site and systemic reactions. Similar proportions of participants achieved an hSBA titer ≥1:8 for all four serogroups regardless of whether 2 or 3 doses were administered in the first year of life. Following a second-year dose, 91-100% of participants achieved the threshold for all 4 serogroups in all schedules regardless of the number of doses in the first year of life. Similar responses were seen with rSBA. Immunogenicity and safety profile of concomitant vaccines was similar whether the MenACYW-TT conjugate vaccine was administered or not., Conclusion: MenACYW-TT conjugate vaccine administered with pediatric vaccines is safe and immunogenic regardless of the schedule and does not affect the immunogenicity or safety of the concomitant vaccines., Clinical Trial Registry: NCT01049035., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: CR, JP, DN, EJ, and MSD currently are, and LMP and XDC were employees of Sanofi Pasteur at the time the study was conducted and hold stock options in Sanofi Pasteur., Inc. MC, JH, AG, and AJ received a grant to carry out the research at their respective study sites., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Type 1 diabetes is an autoimmune disease characterized by progressive loss of pancreatic beta cells. Golimumab is a human monoclonal antibody specific for tumor necrosis factor α that has already been approved for the treatment of several autoimmune conditions in adults and children. Whether golimumab could preserve beta-cell function in youth with newly diagnosed overt (stage 3) type 1 diabetes is unknown., Methods: In this phase 2, multicenter, placebo-controlled, double-blind, parallel-group trial, we randomly assigned, in a 2:1 ratio, children and young adults (age range, 6 to 21 years) with newly diagnosed overt type 1 diabetes to receive subcutaneous golimumab or placebo for 52 weeks. The primary end point was endogenous insulin production, as assessed according to the area under the concentration-time curve for C-peptide level in response to a 4-hour mixed-meal tolerance test (4-hour C-peptide AUC) at week 52. Secondary and additional end points included insulin use, the glycated hemoglobin level, the number of hypoglycemic events, the ratio of fasting proinsulin to C-peptide over time, and response profile., Results: A total of 84 participants underwent randomization - 56 were assigned to the golimumab group and 28 to the placebo group. The mean (±SD) 4-hour C-peptide AUC at week 52 differed significantly between the golimumab group and the placebo group (0.64±0.42 pmol per milliliter vs. 0.43±0.39 pmol per milliliter, P<0.001). A treat-to-target approach led to good glycemic control in both groups, and there was no significant difference between the groups in glycated hemoglobin level. Insulin use was lower with golimumab than with placebo. A partial-remission response (defined as an insulin dose-adjusted glycated hemoglobin level score [calculated as the glycated hemoglobin level plus 4 times the insulin dose] of ≤9) was observed in 43% of participants in the golimumab group and in 7% of those in the placebo group (difference, 36 percentage points; 95% CI, 22 to 55). The mean number of hypoglycemic events did not differ between the trial groups. Hypoglycemic events that were recorded as adverse events at the discretion of investigators were reported in 13 participants (23%) in the golimumab group and in 2 (7%) of those in the placebo group. Antibodies to golimumab were detected in 30 participants who received the drug; 29 had antibody titers lower than 1:1000, of whom 12 had positive results for neutralizing antibodies., Conclusions: Among children and young adults with newly diagnosed overt type 1 diabetes, golimumab resulted in better endogenous insulin production and less exogenous insulin use than placebo. (Funded by Janssen Research and Development; T1GER ClinicalTrials.gov number, NCT02846545.)., (Copyright © 2020 Massachusetts Medical Society.)

Background: Autoantibody screening in type 1 diabetes (T1D) may reduce the chances of potentially life-threatening diabetic ketoacidosis (DKA) at diagnosis by allowing individuals at risk of progression to more actively monitor for and/or manage progression to insulin dependence. We investigated parents' preferences for treatments to delay the onset of insulin dependence in children who are at high risk of developing Stage III T1D. Methods: A web-based survey ( n  = 1501) was administered to a stratified sample of parents (children <18 years) in the United States from an online panel. Parents were told to hypothetically assume that their youngest child would become insulin dependent within 6 months or 2 years and were offered a series of choices between no treatment and two hypothetical treatments that would delay insulin dependence. Random-parameters logit analysis and maximum acceptable risks were used to evaluate the relative importance of treatment benefits and risks. Results: Most parents chose at least one active treatment (2% always chose monitoring only). For parents of children without T1D ( n  = 901), delaying insulin dependence and reducing the risk of long-term health complications and serious infection were the most important treatment attributes. In addition, parents of children with T1D ( n  = 600) also valued reducing the risk of hospitalizations due to DKA. Conclusions: When told to assume their child would develop Stage III T1D, most parents considered active treatments to delay progression. For medicines under development to delay insulin dependence in T1D, the preferences expressed in this survey provide guidance on acceptable benefit-risk trade-offs.

Fatty acid binding protein-4 (FABP4) and FABP5 are two closely related FA binding proteins expressed primarily in adipose tissue and/or macrophages. The small-molecule FABP4 inhibitor BMS309403 was previously reported to improve insulin sensitivity in leptin-deficient Lep(ob)/Lep(ob) (ob/ob) mice. However, this compound was not extensively characterized in the more physiologically relevant animal model of mice with diet-induced obesity (DIO). Here, we report the discovery and characterization of a novel series of FABP4/5 dual inhibitors represented by Compounds 1-3. Compared with BMS309403, the compounds had significant in vitro potency toward both FABP4 and FABP5. In cell-based assays, Compounds 2 and 3 were more potent than BMS309403 to inhibit lipolysis in 3T3-L1 adipocytes and in primary human adipocytes. They also inhibited MCP-1 release from THP-1 macrophages as well as from primary human macrophages. When chronically administered to DIO mice, BMS309403 and Compound 3 reduced plasma triglyceride and free FA levels. Compound 3 reduced plasma free FAs at a lower dose level than BMS309403. However, no significant change was observed in insulin, glucose, or glucose tolerance. Our results indicate that the FABP4/5 inhibitors ameliorate dyslipidemia but not insulin resistance in DIO mice.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) induces degradation of low-density lipoprotein receptor (LDLR) in the liver. It is being pursued as a therapeutic target for LDL-cholesterol reduction. Earlier genome-wide gene expression studies showed that PCSK9 over-expression in HepG2 cells resulted in up-regulation of genes in cholesterol biosynthesis and down-regulation of genes in stress response pathways; however, it was not known whether these changes were directly regulated by PCSK9 or were secondary to PCSK9-induced changes to the intracellular environment. In order to further understand the biological function of PCSK9 we treated HepG2 cells with purified recombinant wild type (WT) and D374Y gain-of-function PCSK9 proteins for 8, 24, and 48 h, and used microarray analysis to identify genome-wide expression changes and pathways. These results were compared to the changes induced by culturing HepG2 cells in cholesterol-free medium, mimicking the intracellular environment of cholesterol starvation. We determined that PCSK9-induced up-regulation of cholesterol biosynthesis genes resulted from intracellular cholesterol starvation. In addition, we identified novel pathways that are presumably regulated by PCSK9 and are independent of its effects on cholesterol uptake. These pathways included "protein ubiquitination," "xenobiotic metabolism," "cell cycle," and "inflammation and stress response." Our results indicate that PCSK9 affects metabolic pathways beyond cholesterol metabolism in HepG2 cells., ((c) 2010 Wiley-Liss, Inc.)

G-protein-coupled bile acid receptor 1 (GPBAR1/TGR5/M-Bar/GPR131) is a cell surface receptor involved in the regulation of bile acid metabolism. We have previously shown that Gpbar1-null mice are resistant to cholesterol gallstone disease when fed a lithogenic diet. Other published studies have suggested that Gpbar1 is involved in both energy homeostasis and glucose homeostasis. Here, we examine the functional role of Gpbar1 in diet-induced obese mice. We found that body weight, food intake, and fasted blood glucose levels were similar between Gpbar1-null mice and their wild-type (WT) littermates when fed a chow or high-fat diet (HFD) for 2 months. However, insulin tolerance tests revealed improved insulin sensitivity in male Gpbar1(-/-) mice fed chow, but impaired insulin sensitivity when fed a HFD. In contrast, female Gpbar1(-/-) mice exhibited improved insulin sensitivity when fed a HFD compared with their WT littermates. Female Gpbar1(-/-) mice had significantly lower plasma cholesterol and triglyceride levels than their WT littermates on both diets. Male Gpbar1(-/-) mice on HFD displayed increased hepatic steatosis when compared with Gpbar1(+)(/)(+) males and Gpbar1(-/-) females on HFD. These results suggest a gender-dependent regulation of Gpbar1 function in metabolic disease.

Common community-acquired infections include those of the upper respiratory tract. In the 1990s, the antimicrobial treatment of upper respiratory tract infections focused on penicillin-resistant Streptococcus pneumoniae. However, following the introduction of a pneumococcal conjugate vaccine, a decrease in invasive pneumococcal disease occurred, and in the case of otitis media a shift towards Haemophilus influenzae as the predominant causative pathogen was observed. Future antimicrobial therapy for outpatient upper respiratory tract infections may need to focus on pathogens such as penicillin-susceptible S. pneumoniae, beta-lactamase-producing H. influenzae, beta-lactamase-negative amoxicillin-resistant H. influenzae and Moraxella catarrhalis. In these circumstances, third-generation oral cephalosporins, such as cefixime and cefdinir, could be increasingly used as an optional first-line therapy in community practice for upper respiratory tract infections suspected to be caused by these key pathogens, as an alternative to amoxicillin-clavulanate.

PCSK9 (proprotein convertase subtilisin/kexin type 9) mediates the post-translational degradation of the LDL receptor (LDLR) and, as a result, modulates serum levels of LDL-cholesterol (LDL-C). Individuals with gain-of-function mutations in the PCSK9 gene exhibit high serum levels of LDL-C, while those with loss-of-function mutations have low serum levels of LDL-C and are protected from heart disease. Similarly, mice lacking the expression of PCSK9 exhibit higher levels of LDLR in the liver and reduced serum cholesterol, while the overexpression of PCSK9 reduces LDLR and results in increased serum cholesterol. Thus, as a novel, validated target for controlling serum levels of LDL-C, PCSK9 has attracted research attention. The biological inhibition of PCSK9 appears feasible, and preclinical programs based on RNAi targeting of the protein are at an advanced stage. In contrast, the development of conventional small-molecule therapeutics to inhibit PCSK9 continues to present challenges.

Introduction: Inhaled short-acting bronchodilators are recommended for the quick relief of bronchospasm symptoms in children including those less than five years of age. However, limited safety data is available in this young population., Methods: Safety data were analyzed from a randomized, double-blind, parallel group, placebo-controlled multicenter, study evaluating albuterol HFA 90microg or 180microg versus placebo three times a day for 4 weeks using a valved holding chamber, Aerochamber Plus and facemask in children birth

G protein-coupled receptor 119 (GPR119) is expressed in pancreatic islets and intestine, and is involved in insulin and incretin hormone release. GPR119-knockout (Gpr119(-/-)) mice were reported to have normal islet morphology and normal size, body weight (BW), and fed/fasted glucose levels. However, the physiological function of GPR119 and its role in maintaining glucose homeostasis under metabolic stress remain unknown. Here, we report the phenotypes of an independently generated line of Gpr119(-/-) mice under basal and high-fat diet (HFD)-induced obesity. Under low-fat diet feeding, Gpr119(-/-) mice show normal plasma glucose and lipids, but have lower BWs and lower post-prandial levels of active glucagon-like peptide 1 (GLP-1). Nutrient-stimulated GLP-1 release is attenuated in Gpr119(-/-) mice, suggesting that GPR119 plays a role in physiological regulation of GLP-1 secretion. Under HFD-feeding, both Gpr119(+)(/)(+) and Gpr119(-/-) mice gain weight similarly, develop hyperinsulinemia and hyperleptinemia, but not hyperglycemia or dyslipidemia. Glucose and insulin tolerance tests did not reveal a genotypic difference. These data show that GPR119 is not essential for the maintenance of glucose homeostasis. Moreover, we found that oleoylethanolamide (OEA), reported as a ligand for GPR119, was able to suppress food intake in both Gpr119(+)(/)(+) and Gpr119(-/-) mice, indicating that GPR119 is not required for the hypophagic effect of OEA. Our results demonstrate that GPR119 is important for incretin and insulin secretion, but not for appetite suppression.

Neuromedin U (Nmu) is a neuropeptide expressed primarily in the gastrointestinal tract and central nervous system. Previous reports have identified two G protein-coupled receptors (designated Nmur1 and Nmur2) that bind Nmu. Recent reports suggest that Nmu mediates immune responses involving mast cells, and Nmur1 has been proposed to mediate these responses. In this study, we generated mice with an Nmur1 deletion and then profiled the responses of these mice in a cutaneous inflammation model utilizing complete Freund's adjuvant (CFA). We report here that mice lacking Nmur1 had normal inflammation responses with moderate changes in serum cytokines compared to Nmur1(+/+) littermates. Although differences in IL-6 were observed in mice lacking Nmu peptide, these mice exhibited a normal response to CFA. Our data argues against a major role for Nmur1 in mediating the reported inflammatory functions of NmU.

Background and Purpose: GPR119 is a G protein-coupled receptor that is preferentially expressed in islet cells and mediates insulin secretion. Oleoyl-lysophosphatidylcholine and oleoylethanolamide (OEA) act as endogenous ligands for this receptor, whereas PSN375963 and PSN632408 are two recently reported synthetic agonists. In this study, we explored mechanisms underlying GPR119-induced insulin secretion. In addition, we assessed the potential utility of the synthetic agonists as tools for exploring GPR119 biology., Experimental Approach: We examined natural and synthetic GPR119 agonist activity at GPR119 in MIN6c4 and RINm5f insulinoma cells. We evaluated insulin secretion, intracellular calcium [Ca(2+)](i), ion channel involvement and levels of cAMP., Key Results: We report that increases in insulin secretion induced by OEA were associated with increased cAMP and a potentiation of glucose-stimulated increases in [Ca(2+)](i). We also demonstrate that ATP-sensitive K(+) and voltage-dependent calcium channels were required for GPR119-mediated increases in glucose-stimulated insulin secretion. In contrast to OEA, the synthetic GPR119 agonist PSN375963 and PSN632408 have divergent effects on insulin secretion, cAMP and intracellular calcium in MIN6c4 cells., Conclusions and Implications: The endogenous ligand OEA signals through GPR119 in a manner similar to glucagon-like peptide-1 (GLP-1) and its receptor with respect to insulin secretion, [Ca(2+)](i) and cAMP. In addition, PSN375963 and PSN632408 substantially differ from OEA and from one another. These studies suggest that the commercially available synthetic agonists, although they do activate GPR119, may also activate GPR119-independent pathways and are thus unsuitable as GPR119-specific pharmacological tools.

Objective: FFAR1/GPR40 is a G-protein-coupled receptor expressed predominantly in pancreatic islets mediating free fatty acid-induced insulin secretion. However, the physiological role of FFAR1 remains controversial. It was previously reported that FFAR1 knockout (Ffar1(-/-)) mice were resistant to high-fat diet-induced hyperinuslinemia, hyperglycemia, hypertriglyceridemia, and hepatic steatosis. A more recent report suggested that although FFAR1 was necessary for fatty acid-induced insulin secretion in vivo, deletion of FFAR1 did not protect pancreatic islets against fatty acid-induced islet dysfunction. This study is designed to investigate FFAR1 function in vivo using a third line of independently generated Ffar1(-/-) mice in the C57BL/6 background., Research Design and Methods: We used CL-316,243, a beta3 adrenergic receptor agonist, to acutely elevate blood free fatty acids and to study its effect on insulin secretion in vivo. Ffar1(+/+) (wild-type) and Ffar1(-/-) (knockout) mice were placed on two distinct high-fat diets to study their response to diet-induced obesity., Results: Insulin secretion was reduced by approximately 50% in Ffar1(-/-) mice, confirming that FFAR1 contributes significantly to fatty acid stimulation of insulin secretion in vivo. However, Ffar1(+/+) and Ffar1(-/-) mice had similar weight, adiposity, and hyperinsulinemia on high-fat diets, and Ffar1(-/-) mice showed no improvement in glucose or insulin tolerance tests. In addition, high-fat diet induced comparable levels of lipid accumulation in livers of Ffar1(+/+) and Ffar1(-/-) mice., Conclusions: FFAR1 is required for normal insulin secretion in response to fatty acids; however, Ffar1(-/-) mice are not protected from high-fat diet-induced insulin resistance or hepatic steatosis.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to low density lipoprotein receptor (LDLR) and induces its internalization and degradation. PCSK9 binding to LDLR is mediated through the LDLR epidermal growth factor-like repeat A (EGF-A) domain. We show for the first time that an EGF-A peptide inhibits PCSK9-mediated degradation of LDLR in HepG2 cells. In addition to LDLR, we show that PCSK9 also binds directly to ApoER2 and mouse VLDLR. Importantly, binding of PCSK9 to either LDLR or mouse VLDLR was effectively inhibited by EGF-A while binding to ApoER2 was less affected. In contrast, LDL receptor-associated protein (RAP), which interacts with LDL receptor repeat type A (LA) domains, inhibited PCSK9 binding to ApoER2 with greater efficacy than either LDLR or mVLDLR. These data demonstrate that while PCSK9 binds several receptors via its EGF-A binding domain, additional contacts with other receptor domains are also involved.

Background: The need for alternative antimicrobial therapy for recurrent and persistent acute otitis media (AOM) in children has raised interest in assessing the efficacy and safety of fluoroquinolones for treatment of these infections., Methods: In an evaluator-blinded, active-comparator, noninferiority, multicenter study, children (6 months to <5 years) were randomized 1:1 to receive levofloxacin (10 mg/kg twice daily) or amoxicillin/clavulanate (14:1; amoxicillin 45 mg/kg twice daily) for 10 days, with evaluations 4-6 days of therapy (visit 2), 2-5 days after completing therapy (visit 3), and 10-17 days after last dose (visit 4). Primary outcome was clinical cure at visit 3 based on resolution of clinical signs and symptoms of AOM., Results: A total of 1650 children were randomized and 1305 were clinically evaluable at visit 3 (630 levofloxacin, 675 comparator). Clinical cure rates were 72.4% (456 of 630) in levofloxacin-treated and 69.9% (472 of 675) in amoxicillin/clavulanate-treated children. Cure rates were also similar for levofloxacin and comparator for each age group (< or =24 months: 68.9% versus 66.2%; >24 months: 76.9% versus 75.1%; respectively). Cure rates at visit 4 were 74.9% and 73.8% in levofloxacin and amoxicillin/clavulanate groups, respectively. The upper limits of the confidence intervals were less than the noninferiority margin of 10% indicating that levofloxacin treatment is noninferior to comparator treatment overall and in both infants (6 months to 2 years) and children 2-5 years. No differences between treatment groups regarding the frequency or type of adverse events were apparent., Conclusions: Levofloxacin was not inferior to amoxicillin/clavulanate for the treatment of recurrent and/or persistent AOM in infants and children.

Mice lacking GPR103A expression display osteopenia. Analysis of mouse quantitative trait loci literature associated with bone mineral density suggested GPR103A ligand P518/Qrfp (chromosome 2qB) as a candidate osteoporosis gene. Promoter and coding regions of mouse P518/Qrfp were sequenced from genomic DNA obtained from the osteoporosis-prone strain SAMP6 and control strains SAMR1, A/J, AKR/J, BALB/c, C3H/HeJ, C57BL/6J, and DBA/2J. Four single-nucleotide polymorphisms (SNPs) were identified in only SAMP6 genomic DNA, g.-1773 T-->C, g.110 A-->G (N37S), g.188 G-->A (R63K), and g.135 T-->C (H45H). The promoter SNP generated a novel neuron-restrictive silencing factor binding site, a repressor that decreases gene expression in nonneuronal tissues. TaqMan analysis demonstrated fivefold lower P518/Qrfp liver expression in SAMP6 versus SAMR1 or C57BL/6J control strains. Tissue distribution of human, mouse, and rat P518/Qrfp and its receptors showed expression in bone and spinal cord. A direct role for P518/Qrfp function in maintaining bone mineral density is suggested.

Functional interleuin-8 (IL-8) receptors (IL-8RA and IL-8RB: CXCR1 and CXCR2, respectively) have been described in human, monkey, dog, rabbit, and guinea pig. Although three IL-8R homologues have been found in rat, only one of these, rat CXCR2, appears to be functional based on responsiveness to ligands. Similarly, CXC chemokines induce biological responses through the murine homolog of CXCR2, but the identification of functional rodent CXCR1 homologues has remained elusive. We have identified and characterized the mouse CXCR1 homologue (mCXCR1). Murine CXCR1 shares 68 and 88% amino acid identity with its human and rat counterparts, respectively. Similar to the tissue distribution pattern of rat CXCR1, we found murine CXCR1 mRNA expression predominantly in lung, stomach, bone marrow, and leukocyte-rich tissues. In contrast to previous reports, we determined that mCXCR1 is a functional receptor. We show predominant engagement of this receptor by mouse GCP-2/CXCL6, human GCP-2, and IL-8/CXCL8 by binding, stimulation of GTPgammaS exchange, and chemotaxis of mCXCR1-transfected cells. Furthermore, murine CXCR1 is not responsive to the human CXCR2 ligands ENA-78/CXCL5, NAP-2/CXCL7, GRO-alpha, -beta, -gamma/CXCL1-3, or rat CINC-1-3. In addition, we show concomitant elevation of mCXCR1 and its proposed major ligand, GCP-2, positively correlated with paw swelling in murine collagen-induced arthritis. This report represents the first description of a functional CXCR1-like receptor in rodents.

Recent work has shown that neuromedin U (NmU), a peptide initially identified as a smooth muscle contractor, may play a role in regulating food intake and energy homeostasis. To further evaluate this putative function, we measured food intake, body weight, energy expenditure and glucose homeostasis in transgenic mice that ubiquitously overexpress murine proNmU. NmU transgenic mice were lighter and had less somatic and liver fat, were hypophagic, and had improved insulin sensitivity as judged by an intraperitoneal insulin tolerance test. Transgenic mice had higher levels of hypothalamic NPY, POMC and MCH mRNA. There was no difference in O2 consumption between genotypes; however, NmU transgenic mice displayed a modest increase in respiratory quotient during food deprivation and refeeding. There were no behavioral disturbances in the NmU transgenic mice that could account for the results (e.g. changes in locomotor activity). When placed on a high-fat diet, transgenic mice remained lighter than wild-type mice and ate less, but gained weight at a rate similar to wild-type mice. Despite the increased weight gain with high-fat feeding, glucose tolerance was significantly improved in the transgenic mice. These findings support the hypothesized role of NmU as an endogenous anorexigenic peptide.

GPR54 is a G-protein-coupled receptor that displays a high percentage of identity in the transmembrane domains with the galanin receptors. The ligand for GPR54 has been identified as a peptide derived from the KiSS-1 gene. KiSS-1 has been shown to have anti-metastatic effects, suggesting that KiSS-1 or its receptor represents a potential therapeutic target. To further our understanding of the physiological function of this receptor, we have generated a mutant mouse line with a targeted disruption of the GPR54 receptor (GPR54 -/-). The analysis of the GPR54 mutant mice revealed developmental abnormalities of both male and female genitalia and histopathological changes in tissues which normally contain sexually dimorphic features. These data suggest a role for GPR54/KiSS-1 in normal sexual development, and indicate that study of the GPR54 mutant mice may provide valuable insights into human reproductive syndromes.

Hemokinin-1 (HK-1) is a recently described mouse tachykinin peptide whose biological functions are not fully understood. To date, a unique receptor for HK-1 has not been identified. Recent studies suggest HK-1 may have a role in immunological functions, but there has been little characterization of HK-1's effects in the central nervous system (CNS). In the present studies, we confirm that HK-1 is an endogenous agonist at all of the known tachykinin receptors, and is selective for the NK1 receptor over the NK2 and NK3 subtypes. CHO cells transfected with the human NK1 receptor released intracellular calcium in response to HK-1. In addition, HK-1 competed with substance P (SP) for binding to mouse NK1 and human NK1 receptors. In vivo central administration of HK-1 to gerbils and mice induced foot-tapping and scratching behaviors, respectively, similar to those observed following central administration of SP or the NK1 receptor agonist, GR-73632. Furthermore, these behavioral effects were blocked by the selective NK1 receptor antagonist, MK-869. Finally, a comprehensive expression analysis of HK-1 demonstrated that HK-1 mRNA is much more broadly expressed than previously reported with expression observed in many brain regions. Together these data demonstrate that HK-1 is a functional agonist at NK1 receptors and suggest that HK-1 may function both centrally and peripherally.

Unlabelled: PepPat, a hybrid method that combines pattern matching with similarity scoring, is described. We also report PepPat's application in the identification of a novel tachykinin-like peptide. PepPat takes as input a query peptide and a user-specified regular expression pattern within the peptide. It first performs a database pattern match and then ranks candidates on the basis of their similarity to the query peptide. PepPat calculates similarity over the pattern spanning region, enhancing PepPat's sensitivity for short query peptides. PepPat can also search for a user-specified number of occurrences of a repeated pattern within the target sequence. We illustrate PepPat's application in short peptide ligand mining. As a validation example, we report the identification of a novel tachykinin-like peptide, C14TKL-1, and show it is an NK1 (neuokinin receptor 1) agonist whose message is widely expressed in human periphery., Availability: PepPat is offered online at: http://peppat.cbi.pku.edu.cn.

Background: The EST database provides a rich resource for gene discovery and in silico expression analysis. We report a novel computational approach to identify co-expressed genes using EST database, and its application to IL-8., Results: IL-8 is represented in 53 dbEST cDNA libraries. We calculated the frequency of occurrence of all the genes represented in these cDNA libraries, and ranked the candidates based on a Z-score. Additional analysis suggests that most IL-8 related genes are differentially expressed between non-tumor and tumor tissues. To focus on IL-8's function in tumor tissues, we further analyzed and ranked the genes in 16 IL-8 related tumor libraries., Conclusions: This method generated a reference database for genes co-expressed with IL-8 and could facilitate further characterization of functional association among genes.

Neuromedin U (NmU) is a neuropeptide involved in various physiological functions such as feeding behavior, muscle contractile activity, and regulation of intestinal ion transport. Recently, two human G protein-coupled receptors have been identified as NmU-specific receptors, NmU-R1 and NmU-R2, which share 55% amino acid identity. It is unclear however, which of the two receptors mediates responses to NmU observed in rodent models. Attempts to define the pharmacological profile of the two receptors are confounded by overlapping expression of the two receptors and a lack of subtype-selective compounds. In order to establish a basis to further our understanding of the function of these receptors, we cloned and characterized the mouse homologues of the two human NmU receptors. Mouse NmU-R1 and mouse NmU-R2 are 79 and 81% identical to their respective human homologues. Expression of NmU-R1 was mainly observed in testis, gastrointestinal (GI) tract, and immune system, while NmU-R2 was primarily expressed in brain tissues. Each mouse receptor was independently expressed in HEK293 cells and demonstrated a dose-dependent calcium flux in response to NmU-8, NmU-23 and NmU-25. In an attempt to identify a synthetic NmU peptide that would exhibit selectivity at one of the two receptors, we examined the functional activity of eight alanine-substituted NmU-8 peptides. These experiments demonstrated that alanine substitution at positions 5 and 7 affects the functional activity of the peptide at both receptors. The arginine residue at position 7 is required for NmU-8 activity at either receptor while alanine substitution at position 5 selectively affects the potency and the efficacy at mNmU-R1. These experiments validate the use of rodent models to characterize NmU function relative to humans and suggest that substitution at Arginine-5 of NmU-8 may provide a receptor selective peptide.

We developed transgenic mice conditionally expressing the neutrophil chemoattracting chemokine KC and the beta-galactosidase gene in multiple tissues. In these transgenic mice, doxycycline treatment induced a strong up-regulation in the expression of KC in several tissues, including heart, liver, kidney, skin, and skeletal muscle. Expression of KC within these tissues led to a rapid and substantial increase in the serum levels of KC (serum KC levels were higher than 200 ng/ml 24 h after treatment). Accordingly, beta-galactosidase expression was also detected after injection of doxycycline and was highest in skeletal muscle, pancreas, and liver. Surprisingly, despite expression of KC in multiple tissues, no neutrophil infiltration was observed in any of the tissues examined, including skin. Doxycycline treatment of nontransgenic mice grafted with transgenic skin caused dense neutrophilic infiltration of the grafts, but not the surrounding host skin, indicating that the KC produced in transgenic tissues was biologically active. In separate experiments, neutrophil migration toward a localized source of recombinant KC was impaired in animals overexpressing KC but was normal in response to other neutrophil chemoattractants. Analysis of transgenic neutrophils revealed that high concentrations of KC in transgenic blood had no influence on L-selectin cell surface expression but caused desensitization of the receptor for KC, CXCR2. These results confirm the neutrophil chemoattractant properties of KC and provide a mechanistic explanation for the paradoxical lack of leukocyte infiltration observed in the presence of elevated concentrations of this chemokine.

Introduction: Sparse recent data are available in the United States regarding the pathogens of acute otitis media (AOM) most likely to be recovered from children recently treated with the two most frequently prescribed antibiotics, amoxicillin or amoxicillin/clavulanate (AMC)., Methods: Of the 704 rural Kentucky children with culture-positive AOM who underwent a single tympanocentesis or culture of otorrhea between 1992 and 1998, 96 pathogens were recovered from 90 children during therapy or within 7 days posttherapy with an aminopenicillin. Identification and susceptibility testing of AOM pathogens were performed by routine National Committee for Clinical Laboratory Standards methods., Results: Pathogens recovered from children with AOM recently treated (0 to 7 days) with amoxicillin (n = 38) and AMC (n = 58), respectively, were as follows: Haemophilus influenzae (beta-lactamase-negative), 16 and 29%; H. influenzae (beta-lactamase-positive), 11 and 22%; penicillin-susceptible Streptococcus pneumoniae, 26 and 12%; intermediately penicillin-nonsusceptible S. pneumoniae (PNSP), 20 and 10%; resistant PNSP 13 and 17%; Moraxella catarrhalis (beta-lactamase-positive), 13 and 7%; and Streptococcus pyogenes, 3 and 2%. H. influenzae was also isolated from 8 (75%) of 12 children treated with high dose AMC ( approximately 80 mg/kg/day amoxicillin component). Significantly fewer children recently treated with amoxicillin were otitis-prone than those given AMC (24% vs. 74%, P < 0.0001)., Conclusions: The predominant pathogen recovered from children with AOM recently treated with amoxicillin was S. pneumoniae (59%) rather than beta-lactamase-producing organisms (24%). H. influenzae was the predominant (51%) pathogen, rather than PNSP (27%), recovered from children recently treated with AMC.

Histamine exerts its numerous physiological functions through interaction with G protein-coupled receptors. Three such receptors have been defined at both the pharmacological and molecular level, while pharmacological evidence hints at the existence of further subtypes. We report here the cloning and characterization of a fourth histamine receptor subtype. Initially discovered in an expressed-sequence tag database, the full coding sequence (SP9144) was subsequently identified in chromosome 18 genomic sequence. This virtual coding sequence exhibited highest homology to the H(3) histamine receptor and was used to generate a full-length clone by polymerase chain reaction (PCR). The distribution of mRNA encoding SP9144 was restricted to cells of the immune system as determined by quantitative PCR. HEK-293 cells transiently transfected with SP9144 and a chimeric G protein alpha-subunit (Galpha(q/i1,2)) exhibited increases in intracellular [Ca(2+)] in response to histamine but not other biogenic amines. SP9144-transfected cells exhibited saturable, specific, high-affinity binding of [(3)H]histamine, which was potently inhibited by H(3) receptor-selective compounds. The rank order and potency of these compounds at SP9144 differed from the rank order at the H(3) receptor. Although SP9144 apparently coupled to Galpha(i), HEK-293 cells stably transfected with SP9144 did not exhibit histamine-mediated inhibition of forskolin-stimulated cAMP levels. However, both [(35)S]GTPgammaS binding and phosphorylation of mitogen-activated protein kinase were stimulated by histamine via SP9144 activation. In both of these assays, SP9144 exhibited evidence of constitutive activation. Taken together, these data demonstrate that SP9144 is a unique, fourth histamine receptor subtype.

Background: The recommendation of the Drug-Resistant Streptococcus pneumoniae Therapeutic Working Group that high-dose amoxicillin, with or without clavulanate, be used to treat acute otitis media (AOM) addressed concerns about the efficacy of existing therapies against drug-resistant S. pneumoniae. This recommendation relied on pharmacodynamic predictions of concentrations of amoxicillin in middle-ear fluid remaining higher than minimum inhibitory concentrations against intermediately resistant S. pneumoniae for >40% of the dosing interval., Objective: This study compared the tolerability and efficacy of cefprozil and high-dose amoxicillin/clavulanate in patients with AOM., Methods: Patients were randomized to receive 10 days of investigator-blinded oral treatment with either cefprozil suspension (30 mg/kg/d in 2 divided doses) or amoxicillin/clavulanate (45/6.4 mg/kg/d) plus amoxicillin (45 mg/kg/d) in 2 divided doses. The primary efficacy end point was the clinical cure rate 4 to 7 days after the end of treatment. Clinical response by age (6 months-<2 years vs > or =2-7 years), disease severity, and unilateral versus bilateral ear infection was also examined. The primary measures of tolerability were the frequency and severity of adverse events and their relation to study drug. Adverse events were either spontaneously reported or elicited during examination and questioning of the patient. Identified adverse events were coded and recorded using the COSTART (Coding Symbols for Thesaurus of Adverse Reaction Terms) system., Results: Three hundred four children between the ages of 6 months and 7 years with > or =1 sign or symptom of AOM were enrolled in the study, and 303 (150 cefprozil, 153 amoxicillin/clavulanate) were treated. Twenty-three patients in each treatment group were not evaluable; thus, 257 children were included in the analysis of evaluable patients. Clinical cure rates were 87% (110/127) with cefprozil and 89% (116/130) with amoxicillin/clavulanate (95% CI for the difference in cure rate, -10.7% to 4.1%). No between-group differences in efficacy were noted by age, disease severity, or unilateral or bilateral involvement. The overall incidence of drug-related adverse events was significantly lower with cefprozil than with amoxicillin/clavulanate (19% vs 32%, respectively; P = 0.008), as was the incidence of diarrhea (9% vs 19%, respectively; P = 0.021). Adverse events prompted discontinuation of therapy in 4 (3%) cefprozil patients and 8 (5%) amoxicillin/clavulanate patients., Conclusions: Based on a search of MEDLINE, this study is the first direct comparison of cefprozil versus high-dose amoxicillin/clavulanate. Cefprozil was as effective as high-dose amoxicillin/clavulanate, with a lower incidence of adverse events.

Neuromedin U is a neuropeptide prominently expressed in the upper gastrointestinal tract and central nervous system. Recently, GPR66/FM-3 (NmU-R1) was identified as a specific receptor for neuromedin U. A BLAST search of the GenBank(TM) genomic database using the NmU-R1 cDNA sequence revealed a human genomic fragment encoding a G protein-coupled receptor that we designated NmU-R2 based on its homology to NmU-R1. The full-length NmU-R2 cDNA was subsequently cloned, stably expressed in 293 cells, and shown to mobilize intracellular calcium in response to neuromedin U. This response was dose-dependent (EC(50) = 5 nm) and specific in that other neuromedins did not induce a calcium flux in receptor-transfected cells. Expression analysis of human NmU-R2 demonstrated its mRNA to be most highly expressed in central nervous system tissues. Based on these data, we conclude that NmU-R2 is a novel neuromedin U receptor subtype that is likely to mediate central nervous system-specific neuromedin U effects.

Objective: To examine the microbiologic and clinical efficacy of a 5-day course of cefdinir in the treatment of tympanocentesis-documented acute otitis media (AOM)., Design: Open label noncomparative trial., Setting: Primary care, ambulatory., Patients: Children ages 6 months through 12 years with signs of AOM and middle ear effusion confirmed by tympanometry in at least one ear., Intervention: Patients underwent tympanocentesis at baseline and received cefdinir 7 mg/kg twice a day for 5 days., Main Outcome Measures: Presumptive eradication of middle ear pathogens determined by clinical cure of signs and symptoms of AOM at end of therapy (Study Days 7 to 9) and Visit 3 (Study Days 16 to 21)., Results: A total of 125 of 177 enrolled children had 134 pathogens isolated by tympanocentesis: Streptococcus pneumoniae, 69 (51.5%); Haemophilus influenzae 44 (32.8%; beta-lactamase-positive in 18 of 44 strains); beta-lactamase-positive Moraxella catarrhalis, 15 (11.2%); and Streptococcus pyogenes, 6 (4.5%). The clinical cure rates by patient in the microbiologically and overall clinically evaluable groups, respectively, were 73% (84 of 115) and 77.4% (130 of 168) at the end of therapy visit and 57.4% (66 of 115) and 61.9% (104 of 168) at Visit 3. Presumptive eradication rates at end of therapy were 8 of 11 (72.7%) and 4 of 8 (50%) for patients with penicillin-intermediate and -resistant S. pneumoniae isolates, respectively. Adverse reactions occurred in 16% of patients, with diarrhea (11%) occurring most frequently., Conclusions: A 5-day regimen of cefdinir was effective in the eradication of the common causative pathogens of nonrefractory AOM, including intermediate penicillin-resistant S. pneumoniae and beta-lactamase-producing organisms. Cefdinir should be considered a suitable second line antibiotic for AOM.

Objective: Two dosage regimens of cefdinir were compared with amoxicillin/clavulanate for the treatment of suppurative acute otitis media (AOM) in children., Methods: This was an investigator-blinded, randomized, comparative, multicenter trial, in which tympanocentesis was performed in 384 patients, ages 6 months to 12 years, who had nonrefractory AOM. Patients were randomized to receive one of three 10-day treatment regimens: cefdinir 14 mg/kg daily (QD; n = 128); cefdinir 7 mg/kg twice a day (BID; n = 128); or amoxicillin/clavulanate 40/10 mg/kg/day divided for use three times a day (TID; n = 128)., Results: Of the 384 enrolled patients 303 were evaluable for clinical efficacy. Clinical success rates were statistically equivalent for the 3 treatment groups at the end of therapy: 85 of 102 (83.3%) for cefdinir QD; 81 of 101 (80.2%) for cefdinir BID; 86 of 100 (86%) for amoxicillin/clavulanate. Of the 197 evaluable patients from whom a susceptible pathogen was recovered, presumptive eradication rates at end of therapy were equivalent: 55 of 65 (84.6%), 54 of 66 (81.8%) and 55 of 66 (83.3%) for cefdinir QD-, cefdinir BID- and amoxicillin/clavulanate-treated patients, respectively. However, presumptive eradication rates for Streptococcus pneumoniae were significantly lower for cefdinir BID (55.2%) than for amoxicillin/clavulanate (89.5%; P = 0.0019) and marginally lower than for cefdinir QD (80%; P = 0.054). Diarrhea was the most common treatment-associated adverse reaction in all groups but was significantly more common in amoxicillin/clavulanate-treated patients (35%) than in patients who had been treated with cefdinir QD (10%, P<0.001) or cefdinir BID (13%, P<0.001)., Conclusions: A 10-day regimen of cefdinir 14 mg/kg QD or 7 mg/kg BID was as clinically effective overall as a 10-day regimen of amoxicillin/ clavulanate 40/10 mg/kg/day divided TID in the treatment of tympanocentesis-confirmed, nonrefractory AOM in children. These data suggest that cefdinir QD may be a better alternative than cefdinir BID for refractory AOM. Both dosing regimens of cefdinir were associated with significantly fewer gastrointestinal adverse reactions than was amoxicillin/clavulanate.

Neuromedin U (NmU) is a 25 amino acid peptide prominently expressed in the upper gastrointestinal (GI) tract and central nervous system. It is highly conserved throughout evolution and induces smooth muscle contraction in a variety of species. Our understanding of NmU biology has been limited because the identity of its receptor was unknown. Here we demonstrate that GPR66/FM-3 is specifically stimulated by NmU, causing the mobilization of intracellular calcium. This response was dose-dependent (EC(50) = 10 nM) and specific in that none of over 1000 ligands tested, including other neuromedins (NmB, C, L, K, N), induced a calcium flux in GPR66/FM-3-transfected cells. The GPR66/FM-3 mRNA is prominently expressed in the upper GI tract of humans, as is the mRNA for NmU, consistent with role for this receptor-ligand pair in regulating the function of this organ system. In addition, we show that whereas neuromedin U is expressed by monocytes and dendritic cells, GPR66/FM-3 is expressed by T cells and NK cells. These data suggest a previously unrecognized role for NmU as an immunoregulatory molecule.

Background: Influenza infection rates are higher in children than in other age groups. This study evaluated the efficacy, safety and tolerability of a 5-day course of twice daily inhaled zanamivir, 10 mg, compared with placebo in the treatment of symptomatic influenza A and B viral infections among children 5 to 12 years of age., Methods: This double blind, randomized, placebo-controlled, parallel group, multicenter study conducted in the Northern Hemisphere during the 1998 and 1999 influenza season enrolled 471 patients with influenza-like symptoms for < or = 36 h. Patients were randomly assigned to zanamivir (n = 224) or placebo (n = 247). Symptoms were recorded on diary cards twice daily during treatment, for 9 days after treatment and for 14 additional days (if still reporting moderate/severe cough and/or taking relief medication)., Findings: A total of 346 (73%) patients were influenza-positive by culture, serology or polymerase chain reaction (65% influenza A, 35% influenza B). Zanamivir reduced the median time to symptom alleviation by 1.25 days compared with placebo among patients with confirmed influenza infection (P < 0.001). Zanamivir-treated patients returned to normal activities significantly faster and took significantly fewer relief medications than placebo-treated patients. Zanamivir was well-tolerated, demonstrating adverse event profiles similar to those of placebo and no clinically significant changes in laboratory findings. Viral susceptibility testing revealed no zanamivir-resistant strains of influenza A or B., Conclusions: Zanamivir was effective in shortening the duration and severity of influenza symptoms and was well-tolerated among children 5 to 12 years of age.

Lymphotactin is unique among chemokines in that it contains only two of four conserved cysteines and may possess a structure less constrained than other chemokines. The viral chemokine vMIP-II, which presumably has a structure similar to that of CC chemokines has been shown to inhibit many chemokine receptors, but its activity at GPR5/XCR1 has not been described. Interestingly, vMIP-II (but not vMIP-I) was found to be a potent antagonist of lymphotactin activity at GPR5/XCR1, extending the range of chemokine classes that this viral protein is known to inhibit to include the C class chemokine. In addition, we have extended previous analyses of GPR5/XCR1 expression and show that this receptor is expressed in leukocyte cells previously shown to be responsive to lymphotactin., (Copyright 2000 Academic Press.)

Clarithromycin, an advanced-generation macrolide antibiotic, has demonstrated excellent in vitro activity against group A beta-hemolytic streptococcus (GABHS). Potent activity against Streptococcus pyogenes and a favorable pharmacokinetic profile have made it a reasonable alternative for treatment of patients with streptococcal pharyngitis. The safety and efficacy of clarithromycin and penicillin V were compared in a randomized, investigator-blind study. Children 6 months to 12 years of age received 5 days of clarithromycin suspension 7.5 mg/kg twice daily (n = 268) or 10 days of penicillin V suspension 13.3 mg/kg three times daily (n = 260). Patients were evaluated for signs and symptoms of pharyngitis, and throat swabs for culture were obtained prior to therapy, at the end of therapy, and at follow-up. Clarithromycin and penicillin V produced comparable rates of clinical success (cure + improvement) at the posttreatment (97% and 94%) and follow-up (81% and 82%) evaluations. The GABHS eradication rate, however, was significantly higher with clarithromycin (94% vs 78%, P < .001). Both drugs were well tolerated; gastrointestinal complaints were similar and mild. Resistance did not occur with the short course of clarithromycin or the standard regimen of penicillin V. Five days' treatment with clarithromycin was superior to 10 days of penicillin in eradicating S. pyogenes.

Identification of chemokine receptors and their associated ligands is crucial to the understanding of most immune reactions. Three human chemokines [I-309, thymus and activation-regulated chemokine (TARC) and macrophage inflammatory protein-1beta (MIP-1beta)] have been reported to be ligands for CC-chemokine receptor 8 (CCR8). In this report, we present evidence that TARC and MIP-1beta did not bind to or induce chemotaxis through CCR8 on a stable transfected cell line (1D-21) and did not bind to CCR8 on in vitro differentiated human CD4(+) Th(2) cell cultures. Also, I-309-dependent calcium mobilization in 1D-21 cells and in Th(2) cells was desensitized by I-309 but not by MIP-1beta or TARC. These results provide strong evidence that, at physiologically relevant concentrations, I-309 is the only known human ligand for CCR8. These data also provide a framework for suggesting minimum requirements for the assignment of chemokine receptor-ligand pairs.

The Kaposi's sarcoma-related herpesvirus (KSHV), also designated human herpesvirus 8, is the presumed etiologic agent of Kaposi's sarcoma and certain lymphomas. Although KSHV encodes several chemokine homologues (viral macrophage inflammatory protein [vMIP]-I, -II, and -III), only vMIP-II has been functionally characterized. We report here that vMIP-I is a specific agonist for the CC chemokine receptor (CCR)8 that is preferentially expressed on Th2 T cells. Y3 cells transfected with CCR8 produced a calcium flux in response to vMIP-I and responded vigorously in in vitro chemotaxis assays. In competition binding experiments, the interaction of vMIP-I with CCR8 was shown to be specific and of high affinity. In contrast to its agonist activity at CCR8, vMIP-I did not interact with CCR5 or any of 11 other receptors examined. Furthermore, vMIP-I was unable to inhibit CCR5-mediated HIV infection. These findings suggest that expression of vMIP-I by KSHV may influence the Th1/Th2 balance of the host immune response.

Lymphotactin (Lptn) is a C chemokine produced predominantly by NK and CD8-positive (CD8+) T cells including gammadelta TCR-positive (TCR+) intraepithelial lymphocytes. Lptn is chemotactic for NK and T cells and likely plays an important role in maintaining the integrity of the epithelium and in mucosal immune responses. In this study, we characterized the immune responses to OVA given intranasally with Lptn to mice. This regimen enhanced OVA-specific serum Ab responses and Ab titers in mucosal secretions. Lptn also enhanced OVA-specific Ab-forming cells in mucosal and systemic compartments. CD4-positive (CD4+) T cells isolated from mucosal compartments and spleens of mice intranasally immunized with OVA plus Lptn displayed higher OVA-specific proliferative responses and greater synthesis of IFN-gamma, IL-2, IL-4, IL-5, IL-6, and IL-10 than did CD4+ T cells from mice given OVA without Lptn. These studies indicate that Lptn has adjuvant properties and suggest that Lptn present in the mucosa has the potential to enhance mucosal and systemic Ab responses through help provided by Th1- and Th2-type cells to link the initial innate signals of the mucosa with the acquired immune system.