"Spontaneous" blastogenic transformation. A monitor of immunosuppression

In vitro cell-mediated immunity after thermal injury is not impaired. Density gradient purification of mononuclear cells is associated with spurious (artifactual) immunosuppression

Mononuclear cells isolated by density gradient centrifugation from the peripheral blood of burn patients, but not healthy volunteers, are contaminated with large numbers of nonmononuclear cells. These contaminating leukocytes could cause artifactual alterations in standard in vitro tests of lymphocyte function. Thus, we compared the in vitro blastogenic response of density gradient purified leukocytes and T-cell purified lymphocytes from 13 burn patients to mitogenic (PHA) and antigenic stimuli. The mitogenic and antigenic response of the patients' density gradient purified leukocytes were impaired compared to healthy volunteers (p less than 0.01). However, when the contaminating nonlymphocytes were removed, the patients' cells responded normally to both stimuli. Thus, density gradient purified mononuclear cells from burn patients are contaminated by leukocytes that are not phenotypically or functionally lymphocytes. Since the lymphocytes from burn patients respond normally to PHA and alloantigens after the contaminating nonlymphocyte cell population has been removed, it appears that in vitro assays of lymphocyte function using density gradient purified leukocytes may give spurious results.

Organ transplantation and the immune response gene. Clinical correlations and donor requirements

Major gains have been made in the area of clinical organ transplantations due to recent studies concerning the human histocompatibility locus (HLA). These basic science findings, along with developments in clinical pharmacology have allowed for a much broader use of donor sources, and a significant prolongation in clinical life span for these transplantation recipients.