CCR2- and CCR2+ corneal macrophages exhibit distinct characteristics and balance inflammatory responses after epithelial abrasion

Macrophages are distributed throughout the body and are crucial for the restoration of damaged tissues. However, their characteristics in the cornea and roles in the repair of corneal injures are unclear. Here we show that corneal macrophages can be classified as CCR2^- macrophages, which already exist in the cornea at embryonic day 12.5 (E12.5) and are similar to yolk sac-derived macrophages, microglia, in phenotype and gene expression, and CCR2⁺ macrophages, which do not appear in the cornea until E17.5. At a steady state, CCR2^- corneal macrophages have local proliferation capacity and are rarely affected by monocytes; however, following corneal epithelial abrasion, most CCR2^- corneal macrophages are replaced by monocytes. In contrast, CCR2⁺ macrophages are repopulated by monocytes under both a steady-state condition and following corneal wounding. Depletion of CCR2⁺ macrophages decreases corneal inflammation after epithelial abrasion, whereas depletion of CCR2^- macrophages increases inflammation of the injured cornea. Loss of either cell type results in a delay in corneal healing. These data indicate that there are two unique macrophage populations present in the cornea, both of which participate in corneal wound healing by balancing the inflammatory response.

Differential expression of hENT1 and hENT2 in colon cancer cell lines

Human equilibrative nucleoside transporters (hENT) 1 and 2, encoded by SLC29A1 and SLC29A2, permit the bidirectional passage of nucleoside analogues into cells and may correlate with clinical responses to chemotherapy in patients with colorectal cancer (CRC). The purpose of this study was to evaluate the expression profiles of SLC29A1 and SLC29A2 in human cancer cell lines. Using quantitative real-time polymerase chain reaction, we comprehensively profiled the transcription levels of SLC29A1 and SLC29A2 in 16 colon cancer cell lines. We validated the ubiquitous and heterogeneous distribution of SLC29A1 and SLC29A2 in human colon cancer cell lines and demonstrated that SLC29A1 was highly expressed in 25% of metastatic cell lines (Colo201 and Colo205) and 62.5% of primary cell lines (Caco2, Colo320, HCT116, RKO, and SW48). For the first time, we showed that both SLC29A1 and SLC29A2 were expressed at lower levels in colon cancer cell lines originating from metastatic sites than from primary sites. These findings indicate that most patients with metastatic CRC (mCRC) may have low hENT1 expression, and treatment with nucleoside analogues may be inefficient. However, some patients still show high hENT1 expression and have a high probability of benefiting from these drugs. Therefore, evaluating transporter expression profiles and different drug responses between primary and metastatic tumors in patients with mCRC is important. Further assessment of the association between hENTs and drug-based treatment of mCRC is required to elucidate the mechanisms of chemotherapy resistance.

Effectiveness of telephone-based interventions on health-related quality of life and prognostic outcomes in breast cancer patients and survivors-A meta-analysis

The aim of this meta-analysis was to evaluate the effect of telephone-based interventions on prognostic outcomes and health-related quality of life (HRQoL) in breast cancer patients and survivors. A systematic search of the Cochrane Library, Web of science, Medline, EMBASE, CNKI and CBM database was carried out. Randomised, controlled trials (RCTs) examining the effects of telephone-based intervention versus a control group receiving no telephone intervention, on prognostic outcomes and HRQoL with breast cancer were included. A meta-analysis was conducted to quantify the effects of telephone-based interventions on anxiety, depression, fatigue, self-efficiency, physiological function, social-domestic function and quality of life. In total, 14 studies involving 2002 participants were included. Due to the effect of telephone-based interventions, statistically significant results were found on anxiety (standard mean difference [SMD] = -0.16, 95% confidence intervals [CI] [0.01, 0.30], p = .04), self-efficiency (SMD = 0.22, 95% CI [-0.34, -0.10], p = .0004), social-domestic function (SMD = 0.19, 95% CI [-0.35, -0.03], p = .02) and quality of life (SMD = 0.54, 95% CI [-1.00, -0.08], p = .02). Although the effects on depression, fatigue and physiological function were in the expected direction, these effects were not statistically significant (p > .05) based on the insufficient evidence.

[Infection of chronic otitis media with Acinetobacter：6 cases report]

Objective:To investigate the clinical characteristics, diagnostic methods and prognosis of patients with chronic otitis media with Acinetobacter infection. Method:Retrospective analysis of clinical data of 6 cases of chronic otitis media complicated with Acinetobacter infection. Including history, clinical manifestations, laboratory examination, audiology, inner ear, CT, MRI imaging characteristics, treatment and prognosis of etc. to summarize the clinical characteristics, diagnosis and treatment of chronic otitis media with Acinetobacter infection. Result:The age was between 17 years old and 61 years old (Median age 30 years) .Two of them was male and 4 were female. Four cases were had underlying diseases. Five cases with main symptom of cholesteatoma, 1 case with earache symptoms, and 1 case with facial paralysis symptoms. Four cases had vary degrees of physical decline and destruction of bone. After surgery treatment, five patients improved ear pus, among 3 cases was cured, 2 cases of recurrence. Conclusion:Chronic otitis media with Acinetobacter infection occurs in the patient with elderly, poor physical constitution. However, the recurrence rate of conventional treatment is higher. The disease has high misdiagnosis rate. Operation combined with sensitive antibiotic therapy is a radical cure method.

Abstract A031: Cancer vaccine formulation dictates synergy with CTLA-4 and PD-L1 checkpoint blockade therapy

Introduction: Therapeutic blockade of the T cell checkpoint receptors, CTLA-4 and PD-1, can cure some patients with metastatic cancer. Primary resistance to checkpoint blockade therapy is likely due to insufficient spontaneous anti-tumor immunity, and might be overcome by tumor-specific vaccination. However, the same 676-patient landmark study1 that led to FDA approval of anti-CTLA-4 for patients with melanoma showed no added benefit to anti-CTLA-4 monotherapy of concurrent vaccination with gp100 peptide in Incomplete Freund's Adjuvant (IFA), which instead significantly decreased overall response rate and disease control rate through an unknown mechanism1.

Experimental Procedure: To understand the parameters that control synergy between checkpoint blockade and anti-cancer vaccination, we modelled vaccination with gp100 peptide in IFA and anti-CTLA-4 therapy in the standard treatment model of established subcutaneous B16 melanoma2. To correct for the fact that B16 melanoma progresses so rapidly that there is no time for multiple cycles of gp100 vaccination as was given to the melanoma patients, we adoptively transferred naive TCR-transgenic pmel-1 CD8+ T cells that specifically recognize the hgp10025-33 epitope.

Results: Paralleling what was observed in patients1, gp100/IFA vaccination did not enhance, but significantly decreased, the therapeutic efficacy of anti-CTLA-4 therapy, even though we found high levels of gp100-specific pmel-1 T cells in the circulation. Anti-CTLA-4 monotherapy increased intratumoral localization of Tyrosinase-related protein-2 (TRP-2), p15E and gp100 melanoma antigen-specific CD8+ effector T cells (Teff), while gp100/IFA vaccination-induced, gp100-specific CD8+ Teff accumulated at the inflamed vaccination site. Combination of gp100/IFA vaccination and anti-CTLA-4 therapy caused TRP-2, p15E and gp100-specific Teff to similarly redistribute to the gp100/IFA vaccination site and away from the tumor site. This T cell redistribution was accompanied by reduced tumor control and was mediated by IFN-γ, CXCR3 and ICAM-1. At vaccination sites, ICAM-1 and VCAM-1 expression lacked clear association with the vasculature, and instead was abundant on SSChiCD11bhiLy6GloLy6ChiF4-80+CCR2+ (inflammatory) monocytes. Inflammatory monocytes infiltrating were accompanied by CD8+ Teff recruitment; and, conversely, when CD8+ Teff level were low so were inflammatory monocytes, indicating CCR2/CXCR3 positive feedback loop between CD8+ Teff and inflammatory monocytes resulting in their accumulation at the vaccination site, and consequent local skin inflammation. Non-persistent vaccine formulations do not induce these undesirable effects and potently synergize with anti-CTLA-4 and anti-PD-L1 checkpoint blockade, resulting in markedly increased anti-tumor activity. In a challenging setting of 7-day established tumors where dual checkpoint blockade cured only 10% of the mice, addition of non-persistent Vesicular Stomatitis Virus encoding gp100 (VSV.gp100) resulted in 67% cure (p < 0.0001, >200d). Correspondently, dual checkpoint blockade with gp100/IFA vaccination did not cure any mice.

Conclusions: Overall, our results indicate persistent vaccine formulations can fail to increase, or even diminish, the efficacy of CTLA-4 and PD-L1 checkpoint-based cancer therapy through divergent trafficking of checkpoint blockade-induced Teff to the vaccination site. Non-persistent vaccine formulations do not induce these undesirable effects and potently synergize with anti-CTLA-4 and anti-PD-L1 checkpoint blockade, resulting in markedly increased anti-tumor activity.

1. Hodi, F.S., et al. Improved survival with ipilimumab in patients with metastatic melanoma. N Engl J Med 363, 711-723 (2010).

2. Fu, T., He, Q. & Sharma, P. The ICOS/ICOSL pathway is required for optimal antitumor responses mediated by anti-CTLA-4 therapy. Cancer Res 71, 5445-5454 (2011).

Citation Format: Yared Hailemichael, Tihui Fu, Amber Woods, Jason Roszik, Kimberly S. Schluns, Victor H. Engelhard, Padmanee Sharma, Willem W. Overwijk. Cancer vaccine formulation dictates synergy with CTLA-4 and PD-L1 checkpoint blockade therapy [abstract]. In: Proceedings of the Second CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; 2016 Sept 25-28; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(11 Suppl):Abstract nr A031.

[Predictor measures on CT for hematoma expansion following acute intracerebral hemorrhage]

OBJECTIVE

To evaluate the worth of solid predictors in acute intracerebral hematoma(ICH) expansions in computer tomography images.

METHODS

A total of 105 patients with acute ICH in The Second Affiliated Hospital of Soochow University during January 2012 to February 2015 were enrolled. CT plain scan, CTA within 6 hours since the symptoms and CT plain scan recheck within 24 hours were executed. Hematoma location, initial volume of hematoma, shape of hematoma, "spot sign" , UHG speed were analyzed with single factor and binary Logistic regression between the patients with and without hematoma expansion.

RESULTS

There were 30 cases with hematoma expansion and 75 cases with no hematoma expansion in 105 patients. In single factor comparisons, hematoma location(χ(2) =13.125, P<0.05), hematoma shape(χ(2) =23.987, P<0.05), spot sign(χ(2) =25.846, P<0.05), UHG speed(χ(2) =20.328, P<0.05) and the initial hematoma volume(t=-3.183, P<0.05) between the hematoma expansions and the non-hematoma expansions made significant differences. In binary Logistic regression, hematoma shape(irregular (P=0.033) and cleavage(P=0.009)), spot sign(P=0.000) and UHG speed(P=0.040) had significant differences between the two groups. ROC curve areas of hematoma shape, spot sign and UHG speed were 0.776(95%CI 0.682-0.870), 0.740(95%CI 0.625-0.855) and 0.720(95% CI 0.604-0.836). The high specificities of hematoma shape(84%), spot sign (88%)and UHG speed(84%)revealed their great reliabilities with equal sensitivity (60%).

CONCLUSION

Hematoma shape, spot sign and UHG speed are solid predictors of hematoma expansion among which spot sign has promising specificity, hematoma shape and UHG speed are more convenient to be observed.

Interdependent IL-7 and IFN-γ signalling in T-cell controls tumour eradication by combined α-CTLA-4+α-PD-1 therapy

Combination therapy with α-CTLA-4 and α-PD-1 has shown significant clinical responses in different types of cancer. However, the underlying mechanisms remain elusive. Here, combining detailed analysis of human tumour samples with preclinical tumour models, we report that concomitant blockade of CTLA-4 and PD-1 improves anti-tumour immune responses and synergistically eradicates tumour. Mechanistically, combination therapy relies on the interdependence between IL-7 and IFN-γ signalling in T cells, as lack of either pathway abrogates the immune-boosting and therapeutic effects of combination therapy. Combination treatment increases IL-7Rα expression on tumour-infiltrating T cells in an IFN-γ/IFN-γR signalling-dependent manner, which may serve as a potential biomarker for clinical trials with immune checkpoint blockade. Our data suggest that combining immune checkpoint blockade with IL-7 signalling could be an effective modality to improve immunotherapeutic efficacy. Taken together, we conclude that combination therapy potently reverses immunosuppression and eradicates tumours via an intricate interplay between IFN-γ/IFN-γR and IL-7/IL-7R pathways.

Identification and functional characterization of four transient receptor potential ankyrin 1 variants in Apolygus lucorum (Meyer-Dür)

As signal integrators that respond to various physical and chemical stimuli, transient receptor potential (TRP) channels fulfil critical functional roles in the sensory systems of both vertebrate and invertebrate organisms. Here, four variants of TRP ankyrin 1 (TRPA1) were identified and cloned from the green plant bug, Apolygus lucorum. Spatiotemporal expression profiling across development and in different adult tissues revealed that the highest relative-transcript levels occurred in first-instar nymphs and antennae, respectively. In Xenopus laevis-based functional assays, Apo. lucorum TRPA1-A (AlucTRPA1-A), AlucTRPA1-B and AlucTRPA1-C were activated by increasing the temperature from 20 to 40 °C with no significant desensitization observed after repeated temperature stimuli. The activation temperature of AlucTRPA1-A and AlucTRPA1-B was < 25 °C, whereas the activation temperature of AlucTRPA1-C was between 25 and 30 °C. Amongst the variants, only AlucTRPA1-A and AlucTRPA1-C were directly activated by high concentrations of allyl isothiocyanate, cinnamaldehyde and citronellal. Taken together, these results suggest that AlucTRPA1 variants may function in vivo as both thermal and chemical sensors, with the four variants potentially mediating different physiological functions. This study not only enriches our understanding of TRPA1 function in Hemiptera (Miridae), but also offers a foundation for developing new pest control strategies.

ICOS Promotes the Function of CD4+ Effector T Cells during Anti-OX40-Mediated Tumor Rejection

ICOS is a T-cell coregulatory receptor that provides a costimulatory signal to T cells during antigen-mediated activation. Antitumor immunity can be improved by ICOS-targeting therapies, but their mechanism of action remains unclear. Here, we define the role of ICOS signaling in antitumor immunity using a blocking, nondepleting antibody against ICOS ligand (ICOS-L). ICOS signaling provided critical support for the effector function of CD4(+) Foxp3(-) T cells during anti-OX40-driven tumor immune responses. By itself, ICOS-L blockade reduced accumulation of intratumoral T regulatory cells (Treg), but it was insufficient to substantially inhibit tumor growth. Furthermore, it did not impede antitumor responses mediated by anti-4-1BB-driven CD8(+) T cells. We found that anti-OX40 efficacy, which is based on Treg depletion and to a large degree on CD4(+) effector T cell (Teff) responses, was impaired with ICOS-L blockade. In contrast, the provision of additional ICOS signaling through direct ICOS-L expression by tumor cells enhanced tumor rejection and survival when administered along with anti-OX40 therapy. Taken together, our results showed that ICOS signaling during antitumor responses acts on both Teff and Treg cells, which have opposing roles in promoting immune activation. Thus, effective therapies targeting the ICOS pathway should seek to promote ICOS signaling specifically in effector CD4(+) T cells by combining ICOS agonism and Treg depletion. Cancer Res; 76(13); 3684-9. ©2016 AACR.

MicroRNA-34a and Impaired FGF19/21 Signaling in Obesity

The obesity epidemic and the urgent need for effective and safe drugs to treat obesity-related diseases have greatly increased research interest in the metabolic hormones, fibroblast growth factor-19 (FGF19, FGF15 in mice), and FGF21. FGF19 and FGF21 function as endocrine hormones that play key roles in energy metabolism and counteract obesity. Importantly, in obese humans and lab animals, circulating FGF19 and FGF21 levels are elevated, and metabolic actions of these hormones are impaired but the underlying mechanisms remained unknown. Recent microRNA (miR) studies have revealed that aberrantly elevated miR-34a in obesity directly targets β-Klotho, the obligate coreceptor for both FGF19 and FGF21, and attenuates metabolic signaling of these hormones. In this review, we will discuss recent findings in the miR and FGF19/21 fields, emphasizing the novel function of obesity-associated miR-34a in attenuation of FGF19/21 metabolic actions, and further discuss miRs, including miR-34a, as potential drug targets for obesity-related diseases.

Resistance and integron characterization of Acinetobacter baumannii in a teaching hospital in Chongqing, China

A total of 189 Acinetobacter baumannii isolates were collected in 2011 from a teaching hospital in Chongqing, China. Susceptibility data showed strains carrying integrons were significantly more resistant to all tested antibiotics that strains lacking integrons. Five types of gene cassettes belonging to class I integrons were identified in this study, and for the first time two types of gene cassettes belonging to class II integrons are reported. Most of the cassettes belong to a class I integron (136/144) encoding arr3, aacA4, dfrA17, aadA5, aadB, cat, blaOXA10 , aadA1, aadA2, dfrA and aacC1. Isolates contained a class I gene cassette; AadA2-HP-dfrA was the prevalent strain in this hospital. A class II integron was detected in eight strains, which contained the type IV fimbriae expression regulatory gene pilR and sulfate adenylyltransferase, suggesting a possible role in multidrug resistance. The major epidemic strains from intensive care unit patients belong to international clone 2. In conclusion, the presence of integrons was significantly associated with multiple drug resistance of A. baumannii in this hospital, and class I integron isolates bearing AadA2-HP-dfrA were the prevalent strain in this hospital.

A TRPA1 channel that senses thermal stimulus and irritating chemicals in Helicoverpa armigera

Sensing and responding to changes in the external environment is important for insect survival. Transient receptor potential (TRP) channels are crucial for various sensory modalities including olfaction, vision, hearing, thermosensation and mechanosensation. Here, we identified and characterized a transient receptor potential gene named as HarmTRPA1 in Helicoverpa armigera antennae. HarmTRPA1 was abundantly expressed in the antennae and labial palps. Transcripts of HarmTRPA1 could also be detected in the head and proboscis. Furthermore, functional analyses of HarmTRPA1 were conducted in the Xenopus Oocyte system. The results showed that the HarmTRPA1 channel could be activated by increasing the temperature from 20 to 45 °C. No significant adaptation was observed when the stimulus was repeated. In addition to thermal stimuli, pungent natural compounds including allyl isothiocyanate, cinnamaldehyde and citronellal also activated HarmTRPA1. Taken together, we infer that HarmTRPA1 may function as both a thermal sensor involved in peripheral temperature detection and as a chemical sensor detecting irritating chemicals in vivo. Our data provide valuable insight into the TRPA1 channel in this moth and lay the foundation for developing novel strategies for pest control.

Pilot-scale comparison of four duckweed strains from different genera for potential application in nutrient recovery from wastewater and valuable biomass production

The application potential of four duckweed strains from four genera, Wolffia globosa 0222, Lemna japonica 0223, Landoltia punctata 0224 and Spirodela polyrhiza 0225, were compared in four parallel pilot-scale wastewater treatment systems for more than 1 year. The results indicated that each duckweed strain had unique potential advantages. Unlike L. japonica 0223 and La. punctata 0224, which grow throughout the year, S. polyrhiza 0225 and W. globosa 0222 do not survive cold weather. For year round performance, L. japonica 0223 was best not only in dry biomass production (6.10 g·m(-2) ·day(-1) ), but also in crude protein (35.50%), total amino acid (26.83%) and phosphorus (1.38%) content, plus recovery rates of total nitrogen (TN), total phosphorus (TP) and CO2 (0.31, 0.085 and 7.76 g·m(-2) ·day(-1) , respectively) and removal rates of TN and TP (0.66 and 0.089 g·m(-2) ·day(-1) , respectively). This strongly demonstrates that L. japonica 0223 performed best in wastewater treatment and protein biomass production. Under nutrient starvation conditions, La. punctata 0224 had the highest starch content (45.84%), dry biomass production (4.81 g·m(-2) ·day(-1) ) and starch accumulation (2.9 g·m(-2) ·day(-1) ), making it best for starch biomass production. W. globosa 0222 and S. polyrhiza 0225 showed increased flavonoid biomass production, with higher total flavonoid content (5.85% and 4.22%, respectively) and high dominant flavonoids (>60%). This study provides useful information for selecting the appropriate local duckweed strains for further application in wastewater treatment and valuable biomass production.

A fast and accurate decoder for underwater acoustic telemetry

The Juvenile Salmon Acoustic Telemetry System, developed by the U.S. Army Corps of Engineers, Portland District, has been used to monitor the survival of juvenile salmonids passing through hydroelectric facilities in the Federal Columbia River Power System. Cabled hydrophone arrays deployed at dams receive coded transmissions sent from acoustic transmitters implanted in fish. The signals' time of arrival on different hydrophones is used to track fish in 3D. In this article, a new algorithm that decodes the received transmissions is described and the results are compared to results for the previous decoding algorithm. In a laboratory environment, the new decoder was able to decode signals with lower signal strength than the previous decoder, effectively increasing decoding efficiency and range. In field testing, the new algorithm decoded significantly more signals than the previous decoder and three-dimensional tracking experiments showed that the new decoder's time-of-arrival estimates were accurate. At multiple distances from hydrophones, the new algorithm tracked more points more accurately than the previous decoder. The new algorithm was also more than 10 times faster, which is critical for real-time applications on an embedded system.

Extended survival and reduced risk of AML progression in erythroid-responsive lenalidomide-treated patients with lower-risk del(5q) MDS

Lenalidomide is the approved treatment for patients with red blood cell (RBC) transfusion-dependent lower-risk myelodysplastic syndromes (MDS) and chromosome 5q deletion (del(5q)). We report the long-term outcomes (median follow-up 3.2 years) in patients treated with lenalidomide in the MDS-003 trial. RBC transfusion independence (TI) ≥ 8 weeks was achieved in 97 of 148 treated patients (65.5%), with a median response duration of 2.2 years. Partial or complete cytogenetic response was achieved by 63 of 88 evaluable patients (71.6%). Median overall survival (OS) was longer in patients achieving RBC-TI ≥ 8 weeks (4.3 vs 2.0 years in non-responders; P<0.0001) or cytogenetic response (4.9 vs 3.1 years in non-responders; P=0.010). Time to acute myeloid leukemia (AML) progression was longer in patients achieving RBC-TI ≥ 8 weeks or any cytogenetic response versus non-responders (P=0.001 and P=0.0002, respectively). In a landmark multivariate analysis, RBC-TI ≥ 8 weeks was associated with prolonged OS (P<0.001) and a trend toward reduced relative risk of AML progression (P=0.080). Among these lower-risk MDS patients with del(5q), lenalidomide was associated with prolonged RBC-TI and cytogenetic responses, which were linked to improved OS and reduced risk of AML progression.

CD4 T cells require ICOS-mediated PI3K signaling to increase T-Bet expression in the setting of anti-CTLA-4 therapy

The transcription factor T-bet controls the Th1 genetic program in T cells for effective antitumor responses. Anti-CTLA-4 immunotherapy elicits dramatic antitumor responses in mice and in human patients; however, factors that regulate T-bet expression during an antitumor response mediated by anti-CTLA-4 remain to be elucidated. We were the first to report that treatment with anti-CTLA-4 led to an increase in the frequency of T cells expressing inducible costimulator (ICOS). In both treated patients and mice, our data revealed that CD4(+)ICOS(hi) T cells can act as effector T cells, which produce the Th1 cytokine IFN-γ. We also showed in a small retrospective analysis that an increased frequency of CD4(+)ICOS(hi) T cells correlated with better clinical outcome and the absence of ICOS or its ligand (ICOSL) in mouse models led to impaired tumor rejection. Here, we show that CD4(+)ICOS(hi) T cells from anti-CTLA-4-treated patients had an increase in signaling via the phospoinositide-3-kinase (PI3K) pathway and an increase in expression of T-bet. An ICOS-specific siRNA transfected into human T cells led to diminished PI3K signaling and T-bet expression. Therefore, we hypothesized that ICOS, and specifically ICOS-mediated PI3K signaling, was required for T-bet expression. We conducted studies in ICOS-deficient and ICOS-YF mice, which have a single amino acid change that abrogates PI3K signaling by ICOS. We found that ICOS-mediated PI3K signaling is required for T-bet expression during an antitumor response elicited by anti-CTLA-4 therapy. Our data provide new insight into the regulation of T-bet expression and suggest that ICOS can be targeted to improve Th1 antitumor responses.

ICOS signaling in CD8+ CTL contributes to the antitumor efficacy (P2122)

The expression of Inducible costimulator (ICOS) on CD8+ CTL and its role in antitumor immunity remains largely unknown. To address this issue, we crossed ICOS-deficient mice with pmel-1 transgenic mice to generate pmel1/ICOS-/- mice. The loss of ICOS in pmel-1CD8+ CTL cells did not affect the expression of other T cell activation markers (e.g. CD25 and CD69) but led to a significant decrease in IFN-gamma production and killing of target tumor cells. Similarly, adoptive transfer of pmel-1 cells into ICOS-ligand knockout mice showed impaired cell proliferation and decreased expression of IFN-gamma and CD107a. Most importantly, when activated ICOS- / - pmel-1 cells were adoptively tranfered into tumor-bearing mice they displayed poor proliferation and diminished antitumor activity as compared to ICOS-intact pmel-1 cells. These results provide direct evidence for the important role of ICOS in CD8+ CTL mediated antitumor immunity and have implications in the development of novel immunotherapy for cancer by manupilation of ICOS pathway.

QTL and epistatic analyses of heterosis for seed yield and three yield component traits using molecular markers in rapeseed (Brassica napus L.)

Aiming to explore the basis of heterosis in rapeseed, QTLs for yield and three yield component traits were mapped and the digenic interactions were detected in an F2 population derived from a cross between two elite rapeseed lines, SI-1300 and Eagle, in this study. Twenty-eight QTLs were detected for the four yield traits, with only two of them detected simultaneously in the Wuhan and Jingmen environments. Additive, partial dominance, dominance, and overdominance effects were all identified for the investigated traits. Dominance (including partial dominance) was shown by 55% of the QTLs, which suggests that dominance is a major genetic basis ofheterosis in rapeseed. At the P < or = 0.01 level with 1000 random permutations, 108 and 104 significant digenic interactions were detected in Wuhan and Jingmen, respectively, for the four yield-related traits using all possible locus pairs of molecular markers. Digenic interactions, including additive by additive, additive by dominance, and dominance by dominance, were frequent and widespread in this population. In most cases (78.3%), the interactions occurred among marker loci for which significant effects were not detected by single-locus analysis. Some QTLs (57.1%) detected by single-locus analysis were involved in epistatic interactions. It was concluded that epistasis, along with dominance (including partial dominance), is responsible for the expression of heterosis in rapeseed.