TNF-a is N-glycosylated, and the glycosylated form exhibits distinct biological activity from the non-glycosylated form.

Densitometry of protein isoforms visualized by 2-DE. Spot trains are normal in human proteins and highlight the presence of multiple isoforms which differ according to their level of post-translational modification. The triangle indicates the theoretical MW and pI of the protein.

Tumor necrosis factor alpha (TNF-a) and the structurally related lymphotoxin-alpha are pro-inflammatory cytokines produced by a variety of immune and non-immune cells in response to multiple stimuli, including bacterial products, viral infections, and T- and B-cell activation.

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