Table 2.

Qualitative assessment of fluorescent staining of tight junction antibodies, where: - indicates negative staining; + indicates weak staining with no consistent structure; ++ indicates moderate staining of tight junctions, with some structure present; +++ indicates strong staining, with consistent structures present

Fixation	Claudin-1	Occludin	ZO-1
4% Paraformaldehyde	–	–	–
0.2% Triton Pre-extraction + 4% Paraformaldehyde	–	–	–
4% Paraformaldehyde + 0.1% Saponin	–	–	+
4% Paraformaldehyde + Acetone	–	–	–
Methanol	+++	–	+++
0.2% Triton Pre-extraction + Methanol	–	–	–
Methanol + 0.1% Saponin	+	–	+
Methanol + Acetone	–	+++	+++
Acetone	–	–	–