CTL-ImmunoSpot® S5 Core Analyzer

CTL-ImmunoSpot® S5 Micro Analyzer

CTL-ImmunoSpot® S5 Macro Analyzer

CTL-ImmunoSpot® S5 UV Analyzer

快速、全自動影像攝取儲存：

ImmunoSpot^TM Analyzer先以高解析度鏡頭捕捉微小孔中膜上呈色影像，儲存成TIF檔或是壓縮成JPEG檔；這些影像可以進一步使用手動、或是自動方式計算斑點數目。高解析度照相技術，輔以全自動影像分析，被認為是提供快速、大量、單細胞、且高靈敏度研究的解決方法。以電腦輔助的影像收集及使用ELISPOT的專用分析軟體，可以大幅地增強ELISPOT技術，使其可以在短時間內客觀並準確地處理大量的實驗數據。

At the very heart of science are exact, objective and reproducible measurements (see figure 1). The precise evaluation of even such pristine ELISPOT results is impossible when the spots are counted visually, as shown in the lower right panel of the figure.

By introducing and patenting ELISPOT image analysis, we converted the previously time-consuming and subjective evaluation of ELISPOT results into an automated and objective process.

Figure 1: Improvement of IFN-ץ ELISPOT assay results using the ImmunoSpot© protocol. Freshly isolated peripheral blood mononuclear cells were cultured for 24h with media or the recall antigen tetanus toxoid (TT). Note the decreased background and increased signal with the ImmunoSpot® protocol ("New").

• Which cytokine spots are produced by antigen-specific T cells (that are to be measured) vs. those produced by bystander cells (being of no T cell diagnostic value)?
• What do small vs. big spots mean?
• Where should the cutoffs be set for minimal/maximal spot size when counting and analyzing the different cytokine ELISPOT results?
• Are measurements made at single-cell resolution?
• In what frequency range are accurate measurements made?
• If there are antagonistic cytokines produced simultaneously, to what extent do they interfere with the results?
• How many replicates are required to produce significant results?

We Orchestrate the Largest Concentrated Effort Around ELISPOT

Starting from its CWRU based academic roots, CTL has grown to become the world leader in cytokine ELISPOT assay development, automated image analysis, and data management. Over forty employees at CTL dedicate their full-time effort specifically to the ELISPOT technology. These efforts are complemented by over 15 academic scientists at CWRU and by close collaboration with the many scientists worldwide.

CTL has been selected as the only ELISPOT reference laboratory by the Cancer Vaccine Consortium (CVC). Dozens of the finest immunology laboratories have entered collaborations contributing invaluable expertise. This alliance constitutes the largest group in the world to further the frontiers of ELISPOT technologies.

The ImmunoSpot® Product Line has Emerged as the Crystallization of Science

We provide scientifically validated ELISPOT analysis equipment, including three analyzer models to meet different user needs and budgets, satellites, accessory software, and data management solutions. In addition, CTL offers image analysis services, ELISPOT wet lab training, image analysis training, and complete contracted research services for clinical trials. Join the community of those who do not compromise in elevating ELISPOT to an exact science!

CTL is committed to pioneering ELISPOT methods and elevating them to an exact science.

EliSpot vs Other Applications

Differences between ELISPOT assays and other approaches for measuring antigen-specific T cell immunity

Every naïve T cell expresses a unique T cell receptor (TCR) which is specific for a single antigen.  In order to be able to recognize potential infinite numbers of microbial antigens and at the same time to distinguish them from self antigens, T cells system relies on an close to infinite number (~10¹²) of different possible T cell specificities. 

Subsequently, the frequencies of T cells recognizing individual antigens are very low.  As a result of the clonal expansion associated with infections, the frequency of antigen-specific effector cells can transiently rise to as high as 1:100, but these frequencies typically settle in the range of 1:10,000 for effector memory or memory cells.  The frequencies of specific T cells in blood after immunizations with subunit vaccines (proteins/peptides), environmental sensitization and in long term anti-microbial immunity rarely exceed the 1:10,000 thresholds. 

Therefore, techniques that measure T cell immunity need to be sensitive enough to reliably detect such rare cells.  In addition to measuring the frequencies of antigen specific T cells, which delineates the magnitude of immunity, it is essential to understand the functions of these T cells.  The quality of T cell immunity depends on whether theses cells are Th1 or Th2 (Tc1/Tc2) type cells and whether they are capable of direct killing.  Sophisticated assays therefore will also provide information on the effector lineage of the antigen-specific T cells. 

Optimized ELISPOT assays measure the magnitude and the quality of T cell immunity at single cell resolution by detecting individual events of antigen-specific T cells that engage in secretion of cytokines and effector molecules such as granzyme B and/or perforin.  The following is a comparison of the performance and utility of ELISPOT assays with other T cell diagnostic techniques including bulk supernatant measurements, Tetramer/Pentamer, and ICS techniques.

Interested in learning more about the advantages and applications of ELISPOT? Download Applications and Advantages of ELISPOT

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