In this study, an increase in the KT ratio associated with HIV infection is caused by decreases in Trp concentrations and increases in KYN concentrations in the serum.
More importantly, when the KYN concentration is increased through immune activation, production of its neuroactive metabolites, such as quinolinic acid, is stimulated.
4] Nonstandard abbreviations: KYN, kynurenine; IDO, indoleamine-2,3dioxygenase; KT, kynurenine-to-tryptophan; PN, peripheral neuropathy; ARD, AIDS-related dementia; and AZT, zidovudine.
Median and 95% confidence interval for Trp ([micro] mol/L), KYN ([micro] mol/L), and KT ratio in different patient groups and correlation with CD4 counts.
It has been consistently shown that renal insufficiency leads to an accumulation of various Kyns (24).
In order to obtain an initial indication of whether the rise of plasma Kyns correlates with the severity of sepsis, we quantified indoleamines in the plasma of 11 patients enrolled in a recent study treating severe sepsis by a novel selective extracorporeal immunoadsorption approach to remove LPS, IL6 and C5a from the circulation.
Thus, the half-life of certain types of Kyns may vary depending on the rate of flow along the pathway.
As a result, these immunoactive Kyns may compromise immune functions.