Peripheral blood lymphoid subsets and long-term clinical course of kidney recipients: a longitudinal study.

A longitudinal study of peripheral blood lymphocyte subsets was performed in 23 renal allograft recipients treated with prophylactic antilymphocyte antibodies, CsA, and steroids. At day 0 samples were obtained before transplantation (Tx), and afterwards at months +1, +3, +6, +9, +12, +24, +36, and +48. In all patients, after the depletion of lymphoid subsets during antilymphocyte antibody treatment, CD8+ lymphocytes recovered and reached higher values than those observed prior to Tx. This was mainly due to an increase in CD8+CD45RA+ lymphocytes; in contrast, the levels of "memory" CD4+ T cells and the CD4+CD62L+ subset remained low during all the follow-up period. In patients with preserved graft function (n=14) (with creatinine levels below 200 micromol/mL), the initial, relative decrease in CD4+ T cells was never reversed and the recovery of CD8+ lymphocytes started early. They also presented a peak of HLA-DR antigen expression at 1 month, not observed in those patients displaying a suboptimal graft function. At 1 month, the patients with suboptimal graft function (n=9) (with creatinine levels above 200 micromol/mL) showed higher number of CD4+ T cells, delayed recovery of CD8+ lymphocytes, and higher percentage of activated lymphocytes from month +3 on than well-functioning kidney recipients. Both CD8+ lymphocytes and HLA-DR+ T cells, found at month + 1 post-Tx, were negatively correlated with the concentration of creatinine along the follow-up. Interestingly, the mean percentage of CD4+CD25+ T cells found 36 and 48 months after Tx were positively correlated with creatinine concentration at these times. These findings indicate that variations in the distribution of lymphocyte subsets are related with a long-term graft outcome. Within the first month after Tx, a rapid recovery of CD8+ lymphocytes, but not of CD4+ T cells, and a peak of HLA-DR expression, are associated with a good graft function. In contrast, long-term expression of activation markers is related with renal dysfunction.

Longitudinal study of the frequency of cytotoxic T cell precursors in kidney allograft recipients.

Clonal deletion or inactivation of donor-specific alloreactive cells are important mechanisms that are believed to account for acquired immune tolerance in allograft recipients. Serial assessment of precursor cytotoxic T lymphocyte frequencies (CTLpf) by limiting dilution analysis (LDA) provides information at the clonal level on changes in the alloimmune response of graft recipients. We performed a longitudinal study of 15 cadaveric kidney recipients before and every 3 months throughout the first year after transplantation (Tx). Pre-Tx values of donor CTLpf showed high interindividual variability without a predictive value for the clinical outcome. All patients with well functioning kidneys had decreased CDLpf at 3 months post-Tx in comparison with pre-Tx values. This decrease was donor-specific in four patients and was permanent in two cases throughout the study. Most patients presented decreased anti-donor CTLpf values from 6 to 9 months, whereas a partial recovery of donor CTLpf was observed in three patients. Reversible acute rejection was diagnosed in three patients, and it was associated with a marked increase in anti-donor CTLpf, returning to pre-Tx values by 9 months post-Tx. In addition, one patient with chronic rejection displayed a transient increase in CDLpf 6 months after Tx. The results of this sequential study indicate the establishment of a state of either hyporesponsiveness or functional clonal inactivation, transient or permanent, which could facilitate allograft acceptance.

IgE antibodies against bovine serum albumin in a case of eosinophilic gastroenteritis.

Eosinophilic gastroenteritis is a disease characterized histologically by an eosinophilic infiltration of the gut. The cause of this disease remains unclear, although both food allergy and food intolerance have been implicated in its pathogenesis. We report the case of a 22-year-old man in whom gastrointestinal symptoms first appeared in childhood, with involvement of mucosa and muscularis layers of stomach and bowel. He presented high IgE blood levels, and his prick test was positive to bovine, pig, and lamb sera. Immunoblots from calf, pig, and lamb sera, incubated with the patient's serum and revealed by autoradiography, demonstrated the presence of a 65-kDa protein band that was recognized by IgE antibodies but not by IgG. This band corresponded to bovine serum albumin, while IgE did not show reactivity with human albumin. These data suggest a possible role for IgE-mediated hypersensitivity mechanisms in the pathogenesis of eosinophilic gastroenteritis.

In vitro donor-specific hyporesponsiveness and T cell subsets in renal allograft recipients.

In order to assess the immune mechanisms triggered by an immunosuppressive regimen consisting of prophylactic antilymphocyte globulin plus low-dose cyclosporine A and steroids, we studied the short-term evolution of both, anti donor in vitro alloresponse and peripheral blood T cell subsets in 21 recipients of a cadaveric kidney allograft. Spleen cells from cadaveric donors and peripheral blood lymphocytes from the respective recipients pretransplant (pre-Tx), at three and six months posttransplant (post-Tx) were obtained to perform one-way mixed lymphocyte cultures and flow cytometry analysis of lymphocyte subsets. The results indicated the development of donor-specific mixed lymphocyte culture (MLC) hyporesponsiveness as early as three months post-Tx, paralleled by a decrease in CD4+CD29+ helper-inducer cells and by an increase in CD8+CD45RA+ suppressor lymphocytes in peripheral blood. These changes were reflected in a very good clinical outcome of the patients. The present results further suggest that suppression of the immune system just before transplantation is a suitable method to induce early specific hyporesponsiveness to the allograft.

Lymphocyte immunophenotyping by flow cytometry in normal adults. Comparison of fresh whole blood lysis technique, Ficoll-Paque separation and cryopreservation.

In the present report we have assessed the extent to which Ficoll-Paque separation and cryopreservation of mononuclear cells alter the measurement of lymphocyte subsets by flow cytometry. Standard Ficoll-Paque separation increased the percentage of CD4+, CD19+ and CD4+CD45RA+ cells, as well as decreasing that of CD8+, and CD4+CD29+ cells, compared to the fresh whole blood lysis technique. Moreover, cryopreservation caused a depletion of CD4+ p80+ cells, but normal whole blood values were restored following a short incubation.

Hypersensitivity reaction after orgotein (superoxide dismutase) administration.

Orgotein is being increasingly used in the treatment of some inflammatory disorders. Up to now no hypersensitivity reaction has been reported. We present the case of an allergic reaction demonstrated by both, "in vivo" and "in vitro" tests. This finding further supports the need for an adequate control during and after orgotein administration.