Host immune status in uraemia III. Humoral response to selected antigens in the rat.

The humoral immune status of patients with uraemia is controversial. In the present experiments a carefully defined animal model, in which a chronic state of moderate and severe uraemia was induced, has been used to resolve conflicting views. The capacity of the uraemia host to respond to immunogenic stimulation was assessed by challenging uraemic animals with bacterial, viral, T cell-dependent and T cell-independent antigens. The experiments have shown that the immune responsiveness of animals with chronic severe uraemia, immunized with sheep red blood cells, Escherichia coli 075, keyhole limpet haemocyanin and phi X174 bacteriophage is comparable to those found in sham-operated and control groups. The results strongly suggest that uraemia per se does not affect the ability of the host to respond to a wide range of antigenic stimuli. This conclusion is important in that it provides a basis for assessing further the immune status of the uraemic host. If uraemic patients do have an immune deficit, one possible explanation is that uraemia potentiates the immunosuppressive activity of some drugs used in the clinical management of these patients.