Serum and bile secretory immunoglobulins and secretory component during the early postoperative course after liver transplantation

Abstract

Secretory component was assayed in serum and bile from 34 patients within 40 days after a first or a second (three cases) liver transplantation. Levels of serum secretory IgA and IgM and of a serum component referred to as immunoreactive free secretory component, identified by its reactivity with monoclonal and polyclonal antibodies specific to secretory component, were significantly elevated in all posttransplant patients compared with 45 healthy subjects and 10 kidney transplant patients (p < 0.0001). The highest serum levels of bound secretory component and of immunoreactive free secretory component were observed in patients with acute rejection. The elevation of immunoreactive free secretory component was significantly higher in patients with rejection as compared with patients with a graft ischemia (p = 0.002) or an uncomplicated postoperative evolution (p = 0.01). The highest levels of immunoreactive free secretory component and secretory IgM were observed in a transplant patient with selective IgA deficiency. No significant difference was seen between the levels of serum immunoreactive free secretory component observed in patients with rejection and those of patients with cytomegalovirus hepatitis or sepsis. Immunoreactive free secretory component, secretory IgA and secretory IgM levels measured in the serum of three patients with primary nonfunction were lower than those observed in the other groups. Immunoreactive free secretory component bile/serum ratios calculated from 16 patients were significantly higher in patients with acute rejection than in infected patients. This study provides new insight into the mechanisms of increase of serum immunoreactive free secretory component, secretory IgA and secretory IgM in various types of liver dysfunction. The increase observed in all the transplant patients (except in ischemia and primary nonfunction) could be the result of liver regeneration. However, the major increase observed in rejection could also be explained both by the cholangiocyte cytolysis and by an enhancement of secretory component synthesis by cytokines involved in the mechanisms of this immune reaction. (HEPATOLOGY 1991;14:1046–1053.)