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21.
Britten CM Gouttefangeas C Welters MJ Pawelec G Koch S Ottensmeier C Mander A Walter S Paschen A Müller-Berghaus J Haas I Mackensen A Køllgaard T thor Straten P Schmitt M Giannopoulos K Maier R Veelken H Bertinetti C Konur A Huber C Stevanović S Wölfel T van der Burg SH 《Cancer immunology, immunotherapy : CII》2008,57(3):289-302
The interpretation of the results obtained from immunomonitoring of clinical trials is a difficult task due to the variety of methods and protocols available to detect vaccine-specific T-cell responses. This heterogeneity as well as the lack of standards has led to significant scepticism towards published results. In February 2005, a working group was therefore founded under the aegis of the Association for Immunotherapy of Cancer ("CIMT") in order to compare techniques and protocols applied for the enumeration of antigen-specific T-cell responses. Here we present the results from two consecutive phases of an international inter-laboratory testing project referred to as the "CIMT monitoring panel". A total of 13 centers from six European countries participated in the study in which pre-tested PBMC samples, synthetic peptides and PE-conjugated HLA-tetramers were prepared centrally and distributed to participants. All were asked to determine the number of antigen-specific T-cells in each sample using tetramer staining and one functional assay. The results of the first testing round revealed that the total number of cells analyzed was the most important determinant for the sensitive detection of antigen-specific CD8(+) T-cells by tetramer staining. Analysis by ELISPOT was influenced by a combination of cell number and a resting phase after thawing of peripheral blood mononuclear cells. Therefore, the experiments were repeated in a second phase but now the participants were asked to change their protocols according to the new guidelines distilled from the results of the first phase. The recommendations improved the number of antigen-specific T-cell responses that were detected and decreased the variability between the laboratories. We conclude that a two-step approach in inter-laboratory testing allows the identification of distinct variables that influence the sensitivity of different T-cell assays and to formally show that a defined correction to the protocols successfully increases the sensitivity and reduces the inter-center variability. Such "two-step" inter-laboratory projects could define rational bases for accepted international guidelines and thereby lead to the harmonization of the techniques used for immune monitoring. 相似文献
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A. Mander C. Gouttefangeas C. Ottensmeier M. J. P. Welters L. Low S. H. van der Burg C. M. Britten 《Cancer immunology, immunotherapy : CII》2010,59(4):619-627
The Cancer Immunotherapy Immunoguiding Program has conducted an IFN-γ ELISPOT proficiency panel to examine the influence of
serum supplementation of test media on assay performance. Sixteen European laboratories analyzed the same PBMC samples using
different locally established protocols. Participants generated two simultaneous data sets—one using medium supplemented with
serum and one without serum. Performances of the two test conditions were compared by quantifying: (1) the number of viable
cells, (2) background spot formation induced in the medium only control and (3) the ability to detect antigen-specific T cell
responses. The study demonstrated that the number of viable cells recovered and the overall background spot production were
not significantly different between the two conditions. Furthermore, overall laboratory performance was equivalent for the
two test conditions; 11 out of 16 laboratories reported equal or greater detection rates using serum-free medium, while 5
laboratories reported decreased detections rates under serum-free conditions. These results show that good performance of
the IFN-γ ELISPOT assay can be achieved under serum-free conditions. Optimization of the protocol for serum-free conditions
should result in excellent detection rates and eliminate the requirement of serum batch and stability testing, allowing further
harmonization of the assay. 相似文献
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Jing?Chen Richard?Dick Jih-Gaw?Lin Ji-Dong?GuEmail authorView authors OrcID profile 《Applied microbiology and biotechnology》2016,100(23):9845-9860
Nitrite-dependent anaerobic methane oxidation (n-damo) process uniquely links microbial nitrogen and carbon cycles. Research on n-damo bacteria progresses quickly with experimental evidences through enrichment cultures. Polymerase chain reaction (PCR)-based methods for detecting them in various natural ecosystems and engineered systems play a very important role in the discovery of their distribution, abundance, and biodiversity in the ecosystems. Important characteristics of n-damo enrichments were obtained and their key significance in microbial nitrogen and carbon cycles was investigated. The molecular methods currently used in detecting n-damo bacteria were comprehensively reviewed and discussed for their strengths and limitations in applications with a wide range of samples. The pmoA gene-based PCR primers for n-damo bacterial detection were evaluated and, in particular, several incorrectly stated PCR primer nucleotide sequences in the published papers were also pointed out to allow correct applications of the PCR primers in current and future investigations. Furthermore, this review also offers the future perspectives of n-damo bacteria based on current information and methods available for a better acquisition of new knowledge about this group of bacteria. 相似文献
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James?S.?SinclairEmail authorView authors OrcID profile Shelley?E.?Arnott 《Oecologia》2017,183(2):441-453
Introduced plants can positively affect population viability by augmenting the diet of native herbivores, but can negatively affect populations if they are subpar or toxic resources. In organisms with complex life histories, such as insects specializing on host plants, the impacts of a novel host may differ across life stages, with divergent effects on population persistence. Most research on effects of novel hosts has focused on adult oviposition preference and larval performance, but adult preference may not optimize offspring performance, nor be indicative of host quality from a demographic perspective. We compared population growth rates of the Baltimore checkerspot butterfly, Euphydryas phaeton, on an introduced host, Plantago lanceolata (English plantain), and the native host Chelone glabra (white turtlehead). Contrary to the previous findings suggesting that P. lanceolata could be a population sink, we found higher population growth rates (λ) on the introduced than the native host, even though some component parameters of λ were higher on the native host. Our findings illustrate the importance of moving beyond preference–performance studies to integrate vital rates across all life stages for evaluating herbivore–host plant relationships. Single measures of preference or performance are not sufficient proxies for overall host quality nor do they provide insights into longer term consequences of novel host plant use. In our system, in particular, P. lanceolata may buffer checkerspot populations when the native host is limiting, but high growth rates could lead to crashes over longer time scales. 相似文献
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Joachim?BreckowEmail authorView authors OrcID profile Samaneh?Emami Sara?Amalhaf Arwin?Beshgard Jonas?Buermeyer Kaija?Spruck 《Radiation and environmental biophysics》2018,57(2):89-98
The radiation detriment in ICRP 103 is defined as the product of the organ-specific risk coefficient and the damage that may be associated with a cancer type or hereditary effect. This is used to indicate a weighted risk according to the radiation sensitivity of different organs and the severity of damage that may possibly arise. While the risk refers to radiation exposure parameters, the extent of damage is independent of radiation. The parameters that are not affected by radiation are lethality, impairment of quality of life, and reduced life expectancy, which are considered as quantities associated with the severity of disease or damage. The damage and thus the detriment appear to be mostly affected by lethality, which is the quotient of the age-standardized mortality rate to the incidence rate. The analysis of the detriment presented in this paper focuses on the influence of the lethality on the detriment from 1980 to 2012 in the USA and Germany. While the lethality in this period covering more than three decades has decreased approximately linearly by 30% (both USA and Germany), within the same period the detriment declined only by 13% in the USA and by 15% in Germany. If only based on these two countries, an update on the detriment parameters with reference to 2007, when ICRP 103 was released, would result in a reduced weighted risk, i.e. the radiation detriment would be reduced by 10 to 15% from originally 5.7% per Sv for the whole population to roughly 5% per Sv. 相似文献
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Mariëtte I. E. van Poelgeest Valeria V. Visconti Zohara Aghai Vanessa J. van Ham Moniek Heusinkveld Maarten L. Zandvliet A. Rob P. M. Valentijn Renske Goedemans Caroline E. van der Minne Els M. E. Verdegaal J. Baptist M. Z. Trimbos Sjoerd H. van der Burg Marij J. P. Welters 《Cancer immunology, immunotherapy : CII》2016,65(12):1451-1463
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Background
Obligate asexual reproduction is rare in the animal kingdom. Generally, asexuals are considered evolutionary dead ends that are unable to radiate. The phytophagous mite genus Bryobia contains a large number of asexual species. In this study, we investigate the origin and evolution of asexuality using samples from 111 populations in Europe, South Africa and the United States, belonging to eleven Bryobia species. We also examine intraspecific clonal diversity for one species, B. kissophila, by genotyping individuals from 61 different populations. Knowledge on the origin of asexuality and on clonal diversity can contribute to our understanding of the paradox of sex. 相似文献30.
Elise Glattard Ingeborg D. Welters Thomas Lavaux Arnaud H. Muller Alexis Laux Dan Zhang Alexander R. Schmidt Fran?ois Delalande Beno?t-Joseph Laventie Sylvie Dirrig-Grosch Didier A. Colin Alain Van Dorsselaer Dominique Aunis Marie-Hélène Metz-Boutigue Francis Schneider Yannick Goumon 《PloS one》2010,5(1)