Host parasite relationship in hydatidosis: comparative analysis of hydatid cyst fluid and sheep serum.

Various biochemical and physiological characteristics of fresh sheep serum were estimated and compared with those of pooled hydatid cyst fluid (HCF), isolated from Echinococcus granulosus cysts of ovine origin. Concentrations of the following compounds were determined: total protein, total albumin, total lipids, triglycerides, cholesterol, high density, low density and very low density lipoproteins, glucose, bilirubin, creatinine, uric acid, urea, calcium, inorganic phosphate, iron, sodium and potassium. Total activities of the following enzymes were measured: glutaminate-oxaloacetate transaminase, glutaminate-pyruvate transaminase, L-gamma-glutamyl transferase, alkaline phosphatase and alpha-amylase. Osmolarity and pH were also determined and total proteins were subjected to acetate cellulose electrophoresis. It was shown that compounds that are related to the carbohydrate and lipid metabolism, as well as nitrogenous catabolism, were predominantly present in HCF when compared with sheep serum. In contrast, the HCF contained few proteins and showed a low activity of enzymes related to protein metabolism. HCF, although osmotically comparable to serum of a putative host, is characterized by high levels of sodium and potassium. Microscopically, ammonium urate, amorphous phosphate and calcium carbonate crystals are found. The results are discussed in view of cestode physiology and metabolical (in-)dependence of hydatid cysts.