Examining the amounts of neopterin and kynurenine in human colostrum milk

Colostrum is a breast fluid produced by humans, cows, and other mammals before breast milk is released. It's very nutritious and contains high levels of antibodies, which are proteins that fight infections and bacteria. Colostrum promotes growth and immunity improves gut health in infants and newborn animals. Neopterin, a non-conjugated pteridine derivative, is a sensitive biomarker of cellular immune response, and it is released from human monocyte/macrophages by the stimulation of interferon gamma (IFN-g). It is known that detection of neopterin levels in biological samples provides information about the cellular immune condition. Another biomarker which reflects cellular immunity is the enzyme indoleamine 2,3-dioxygenase, which plays a role in the formation of kynurenine (Kyn) by consuming tryptophan (Trp) in the tissues. Although there are a number of studies examining the neopterin, tryptophan and kynurenine levels in various biological samples, they are hardly ever detected in human milk. The main aim of the thesis study was to detect neopterin concentrations and the ratio of kynurenine to tryptophan in human colostrum milk samples. Neopterin levels of the milk samples were determined by an enzyme immunoassay while kynurenine and tryptophan levels were analyzed by high performance liquid chromatography method. Milk samples were collected in the first breasting time as colostrum samples (n=17) and stored at -20°C until analy-sis. It has been detected that the mean neopterin concentrations and Kyn/Trp ratios in colostrum samples were 4-5 times higher than the childhood serum levels, respectively.