Moreover, there was a significant correlation between serum anti-TNF levels and uninflamed-tissue levels that was not present for tissue samples with evidence of inflammation.
Within tissue specimens, there was a positive correlation between mild to moderate mucosal inflammation grades and TNF levels and between mild to moderate mucosal inflammation grades and anti-TNF levels. With more severe inflammation, however, tissue levels of anti-TNF were lower.
In patients with active inflammation, the ratio of anti-TNF in tissue to local TNF levels appeared to be decreased, resulting in lower levels of tissue anti-TNF despite elevated levels of serum anti-TNF.
Neither C-reactive protein nor serum TNF levels were useful for identifying patients with mucosal inflammation.
"Importantly," the researchers note, "in moderately to severely inflamed tissue, the anti-TNF to TNF ratio was lower, implying that there was insufficient anti-TNF to neutralize the TNF."
