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ELISPOT severe

Merged or Indistinguishable Spots

Symptom
Spots merge together and become indistinguishable, making it impossible to count individual cytokine-secreting cells. This results in large, confluent areas instead of discrete spots.
Common Causes
  1. 1 Over-stimulation causing excessive cytokine/protein secretion by cells
  2. 2 Prolonged cell culture exceeding 24 hours leading to excessive cytokine production
  3. 3 Too many cells per well (exceeding optimal 1-2 × 10⁵ cells per well range)
  4. 4 Excessive primary antibody concentration during coating step
Solutions
  1. 1 Reduce stimulant concentration in culture media or shorten stimulation time
  2. 2 Limit cell culture incubation to maximum 24 hours
  3. 3 Optimize and reduce cell number per well to 1-2 × 10⁵ cells
  4. 4 Reduce primary antibody concentration during coating step
Related Video (2)
Mabtech ★ 85
ELISpot tutorial: step-by-step full assay protocol
"Step-by-step protocol tutorial directly teaches correct technique execution, including cell stimulation conditions and spot formation that would help prevent over-stimulation artifacts"
Animated biology With arpan ★ 72
Elispot assay ( assay to determine cytokine producing cells)
"Introduces ELISpot fundamentals and single-cell detection principles, providing context for understanding why spot discreteness matters and how proper assay design prevents merging"
Source: abcam.com ↗
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