Complete IHC Immunohistochemistry Protocol for Beginners

critical

Mouse-on-Mouse Cross-Reactivity in Tissue Staining

High background when using mouse primary antibodies on mouse tissue, caused by secondary antibody binding to endogenous mouse immunoglobulins and Fc receptors rather than only the primary antibody.

💡 4 · ✓ 4

severe

High Background from Excessive Antibody Concentrations

Elevated background staining throughout tissue sections due to excessively high concentrations of primary or secondary antibodies leading to non-specific binding.

💡 4 · ✓ 5

severe

Mouse-on-Mouse (MOM) Background

High background staining when using mouse primary antibody on mouse tissue. Secondary antibody binds endogenous mouse IgG throughout the tissue, creating non-specific signal.

💡 3 · ✓ 4

severe

Residual Reagent Background from Inadequate Washing

Elevated background signal caused by residual fixative or unbound antibodies remaining on tissue sections between procedural steps, producing false-positive staining.

💡 5 · ✓ 5

severe

Inadequate Detection System Sensitivity

Weak signal or no staining despite proper primary antibody performance. Standard HRP-conjugated secondary antibodies fail to provide sufficient signal amplification.

💡 4 · ✓ 4

moderate

Nuclear protein not detected due to insufficient permeabilization

No staining observed when targeting nuclear proteins. Antibody cannot access nuclear compartment despite proper antibody concentration and incubation time.

💡 3 · ✓ 4

moderate

High Background Staining in IHC

Excessive background signal obscuring specific staining. Non-specific binding observed throughout tissue sections, making interpretation difficult.

💡 5 · ✓ 5

moderate

Inadequate Washing Steps Causing Poor Contrast

High background persists with poor contrast between positive signal and background despite other optimization steps, making interpretation difficult.

💡 4 · ✓ 4