The following pages show positive control probe images with standard and mild pretreatment conditions. Optimal pretreatment condition is indicated for each tissue type.
2.2.1 Comparison of mild and standard pretreatment conditions for recommended positive control probe per tissue type
Positive control probe: Cl-POLR2A
Tissue: Spleen
Pretreatment: Standard

Pretreatment: Mild

Observation: Loss of cell boundary using standard pretreatment.
Positive control probe: Cl-POLR2A
Tissue: Lymph node
Pretreatment: Standard

Pretreatment: Mild

Observation: Loss of cell boundary using standard pretreatment.
Positive control probe: Cl-POLR2A
Tissue: Thymus
Pretreatment: Standard

Pretreatment: Mild

Observation: Loss of cell boundary using standard pretreatment.
Positive control probe: Cl-POLR2A
Tissue: Retina (eye)
Pretreatment: Standard

Pretreatment: Mild

Observation: Standard pretreatment causes more cell detachment and reduced signals.