Characterization of the inflammatory cells in progressing tumor-like alveolar hydatid cyst. 2. Cell surface receptors, endocytosed immune complexes and lysosomal enzyme content.

Alveolar hydatid cysts (LCM) grow progressively and contribute significantly to the morbidity of hydatid-hosts. To examine whether modifications in immune effector parameters correlate with the pattern of LCM growth, in vivo experiments were carried out in C57BL/6J mice infected intraperitoneally with LCM. Immigrant peritoneal and intra-LCM leukocytes were tested for the loss of cell surface receptors, membrane-bound and internalized immune complexes (ICs) and lysosomal enzyme contents during the restrictive and progressive growth phases of the LCM. The proportion of Fc and C3b receptor-bearing intra-LCM leukocytes decreased 2-fold and 31 to 72% of the leukocytes contained ICs during the progressive phase of the LCM. Acid phosphatase and beta-glucuronidase activities of macrophages declined sharply during the restrictive phase but they gradually increased as the infection progressed. IC-mediated dysfunction of effector leukocytes and modulation of antibody dependent cell cystolysis mechanism are discussed in murine hydatidosis.