Biomaterial‐Associated Infection with Candida albicans in Mice

Abstract

Candida yeasts are frequently isolated from patients with continuous ambulatory peritoneal dialysis peritonitis or other biomaterial‐associated infections. The mouse model of candidal peritonitis was used to study the interaction of Candida cells with end‐point attached heparinized polyethylene (H‐PE) and with polymorphonuclear leukocytes (PMNs) or macrophages (Mφ). Two Candida strains differing in cell surface hydrophobicity and in expression of fibronectin (Fn) binding were used for the study. Cells of both Candida strains adhered at higher numbers to H‐PE surfaces preadsorbed with Fn or with human dialysis fluid (HDF) than to non‐modified H‐PE, supporting a role of Fn in mediating adhesion. C. albicans 4016 cells expressing low hydrophobicity and low binding of soluble Fn demonstrated stronger adhesion to PMNs than the more hydrophobic C. albicans 3248 yeasts, which express high binding of soluble Fn. However, C. albicans 4016 cells were more resistant to phagocytic killing and were hardly eradicated in intraperitoneally infected mice. The animals depleted in PMNs by treatment with CY were neither able to eradicate C. albicans 3248 (rapidly eliminated by normal mice) nor C. albicans 4016 yeasts (with a tendency to persist in the tissues of normal mice).

Effector function of leucocytes from susceptible and resistant mice against distinct isolates of Candida albicans

“…Candida strains derived from environmental sampling were more resistant to killing by human neutrophils than those isolated from humans or birds, but the properties of the yeasts that were associated with susceptibility and resistance were not identified 7 . A comparison of two Candida strains differing in cell surface hydrophobicity and in fibronectin (Fn) binding showed that the strain expressing a low hydrophobicity and low binding of soluble Fn was more resistant to neutrophil killing and persisted longer in i.p.‐infected mice than the strain with a higher hydrophobicity and higher binding of soluble Fn, 8 and differences in other properties, such as proteinase production, are also associated with differential susceptibility to killing by phagocytic cells 9 . However, little is known about the relative efficiency of phagocytosis and killing of various Candida isolates by neutrophils and macrophages from different inbred strains of mice and its correlation to susceptibility and resistance.…”

In vitro effects of zirconia and alumina particles on human blood monocyte-derived macrophages: X-ray microanalysis and flow cytometric studies

“…12,13 Reduced bactericidal activity of phagocytes has been observed following biomaterial implantation. 14,15 These phagocytosing cells have been shown to undergo an associated respiratory burst in response to a stimulus (reviewed by Rossi et al 16 ). The oxidative burst, which is characterized by the generation of reactive oxygen species (ROS) as superoxide, hydrogen peroxide, hydroxyl radicals, and singlet oxygen, has been used to test hemodialysis membrane biocompatibility in vitro.…”

Specific immune response to staphylococcal antigens during long-lasting biomaterial implantation

“…In previous papers we showed that long‐lasting i.p. implantation of H‐PE in mice caused changes in the differentiation of bone marrow‐derived monocytes, a reduction of the bactericidal activity of phagocytes and a decrease in the host's ability to eradicate staphylococci [5–7].…”

“…As we previously demonstrated, polymorphonuclear leukocytes and macrophages from mice implanted for 2 months with heparinized polyethylene (H‐PE) showed a marked decrease in the bactericidal activity against staphylococci [5]and Candida albicans yeasts [6]. Moreover, long‐lasting implantation caused evident changes in the differentiation of bone marrow‐derived monocytes [7].…”

“…Moreover, long‐lasting implantation caused evident changes in the differentiation of bone marrow‐derived monocytes [7]. As a consequence of this, the animals under long‐lasting implantation presented a diminished ability to eradicate bacteria, particularly those colonizing the biomaterial surface [5, 6, 8]. In this paper, we asked the question whether long‐lasting implantation of H‐PE affects the specific immune response to staphylococcal antigens.…”