A simple method to reduce the background and improve well-to-well reproducibility of staining in ELISPOT assays

The enzyme-link-ed immunospot (ELISPOT) assay due to its high sensitivity i s widely used for the detection of secreted cytokines at the single-cell le vel. Quality of staining is the key for accurate detection of spots and the ir subsequent quantification in ELISPOT assays. A simple technique employin g regular aluminum foil has been developed to improve the quality of staini ng. In plates wrapped with aluminum foil non-specific background staining a nd artifacts were reduced or abolished. Application of aluminum foil allowe d better contrast of specific spots as well as their uniform distribution a cross the filter membrane. This technique provides an inexpensive and relia ble tool for large-volume immune system cells screening by improving well-t o-well reproducibility in ELISPOT plates. (C) 2001 Elsevier Science B.V. Al l rights reserved.