The influence on pretransplant blood transfusions from random donors on immune parameters affecting cadaveric allograft survival

The number of pretransplant blood transfusions (BT) from random donors influences the recipient's immune response status and suppressor cell number and function, as well as allograft survival. The 54% one-year survival rate for 104 cadaveric renal allograft recipients treated with azathioprine and prednisone was divisible into two groups: 74.5% in 51 patients receiving greater than 5 BT and 34% for 53 patients with less than 5 BT (P less than 0.02). Transfusions enhanced the benefit of HLA A, B, and DR compatibility on graft survival: 33 recipients of well-matched grafts (less than 2 A, B, and 0-1 DR mismatches) had a one-year survival rate of 94% when pretreated with greater than 5 BT, compared with 38% when receiving less than 5 BT (P less than 0.05). The graft survival of 73% (36/49) displayed by patients determined preoperatively to be weak immune responders was significantly better than the 36% survival (20/55) demonstrated by strong immune responders (P less than 0.01). The transfusion history correlated with immune responder status: 76% (39/51) of patients receiving greater than 5 BT were weak immune responders, whereas 81% (43/53) of patients receiving less than 5 BT were strong immune responders (P less than 0.001). Ninety-two percent (12/13) of patients with greater than 5 BT, but only 58% (10/17) of patients with less than 5 BT, had a normal number of OKT8+ T suppressor cells. Only 1 X 10(5) mononuclear cells from patients with greater than 5 BT rather than 4 X 10(5) cells from patients with less than 5 BT caused 50% suppression of a third-party MLC. Thus, patients receiving greater than 5 BT are more likely to display weak immune responses, normal numbers of OKT8 cells, strong suppressor function in vitro, and prolonged allograft survival.     

Immunoregulatory mechanisms in cyclosporine-treated renal allograft recipients

Cyclosporine (CsA)-treated recipients of a primary cadaveric (CAD) renal allograft were postoperatively evaluated for their donor and nonspecific immune responsiveness. Recipients with posttransplant (Tx) T helper (TH):T suppressor (TS) cell ratios less than 1.0 (averaged for the first 0-30 post-Tx days) had significantly better one-year serum creatinines (SCr) of 1.8 +/- 0.7 vs. 2.3 +/- 0.6 for recipients with TH:TS ratios greater than 1.0, P less than 0.05. Significantly fewer rejection episodes (30 vs. 57) and immune graft losses (10 vs. 19) were experienced by recipients with TH:TS ratios less than 1.0 vs. greater than 1.0, P less than 0.001 and 0.05, respectively. Recipients with TH:TS ratios less than 1.0 vs. greater than 1.0 displayed significantly lower post-Tx panel mixed lymphocyte culture (PMLC) stimulation indices (SI) of 24 +/- 11 vs. 38 +/- 6, P less than 0.05 and donor MLC SI of 15 +/- 6 vs. 31 +/- 8, P less than 0.05, respectively. Moreover, the post-Tx:pre-Tx donor MLC ratio of 0.58 +/- 0.2 vs. 1.1 +/- 0.32 was significantly lower in recipients with TH:TS ratios less than 1.0 vs. greater than 1.0, P less than 0.05. The suggested donor hyporesponsiveness in recipients with post-Tx TH:TS ratios less than 1.0 was further investigated by studying 46 CsA-treated allograft recipients for their ability to display regulatory T cell or adherent monocyte MLC suppressor activity. With a mean follow-up time of 5 +/- 4 months (range 0.5-14 months) we observed that 46% (21/46) of the patients displayed T cell suppressor activity, including 35% (16/46) with T-donor-specific and 46% (21/46) with T non-specific MLC suppressor activity. Additionally, 59% (27/46) of the patients also displayed nonspecific adherent monocyte MLC suppression. Recipients displaying either T cell or adherent monocyte suppression experienced significantly fewer rejection episodes than patients with no suppressor cell activity (P less than 0.05). Moreover, patients with T cell suppressor activity displayed a significantly lower panel and donor MLC vs. patients not displaying T suppressor activity (P less than 0.05. and 0.05, respectively). Finally, there was a significant correlation between the display of T cell suppressor activity in patients who were matched with their donors at the HLA-DR locus vs. no display of T suppressor activity in those patients unmatched with their donors at the HLA-DR locus.     

Successful transplantation of 100 untransfused cyclosporine-treated primary recipients of cadaveric renal allografts

This report examines the effect of pretransplant (pre-Tx) blood transfusions (BT) on the patient and graft survival results of 320 cyclosporine (CsA) and prednisone (Pred)-treated primary (1 degree) recipients of cadaveric (CAD) donor renal allografts. The 320 CsA-Pred treated 1 degree-CAD recipients included 100 pre-Tx untransfused (O-BT) and 220 transfused patients. The overall patient survival at 12, 24, and 36 months post-Tx were 94%, 94%, and 93%, respectively. There were no differences observed in graft survivals at 12, 24, or 36 months post-Tx whether patients received 0, 1-4, greater than or equal to 5-10 or greater than 10 pre-Tx BTs. A mean serum creatinine of 1.9 +/- 0.7 mg/dl was comparable among all BT groups at 12, 24, and 36 months post-Tx. The frequency of rejection episodes--namely, 37% for O-BT and 36% for greater than O-BT were identical. High-risk patients (greater than 45 years of age, diabetics, or blacks) were comparably distributed in O-BT and greater than O-BT groups and did not impact on the data. Similarly, increasing panel-reactive antibodies (PRA), associated with increasing numbers of pre-Tx BTs, did not influence the data. When HLA A, B, and DR matching results were combined with the BT groupings no differences were observed in patient or graft survivals. Poorly matched and untransfused recipients did as well as well-matched, transfused recipients. These findings suggest that CsA-Pred immunosuppressive therapy allows for successful 1 degree-CAD renal allograft transplantation without the need for pretransplant blood transfusion conditioning or matching of donor HLA A, B, and DR antigens to recipients.     

An apparent paradoxical effect of pretransplant blood transfusions. Its association with decreased anti-HLA antibody formation following unsuccessful renal transplantation

Many potential renal transplant recipients develop multispecific anti-HLA antibodies after a previous unsuccessful transplant. Therefore, it became important to analyze factors that could predispose to multispecific anti-HLA antibodies in the hope of preventing their occurrence because their presence hinders early retransplantation. In these studies, we elected to retrospectively analyze the impact of previous transfusions and the degree of HLA-A,B antigen mismatch on the development of these antibodies. Patients transplanted within the South Eastern Organ Procurement Foundation ( SEOPF ) after January 1977 were analyzed. All patients in these studies were immunosuppressed with prednisone and azothioprine . Antibodies to HLA antigens were determined in a complement-dependent microcytotoxicity assay utilizing recipient's sera and lymphocyte cell panels from random donors. Multispecificity of antibody was quantitated and expressed as the percentage of reactivity to lymphocyte panel (PRL). Only patients who lost their first cadaveric kidney allograft, and who, in addition, had a peak of less than 15% pretransplant and no prior pregnancies were analyzed. Peak posttransplant PRL had to be determined within 3 months after allograft failure. In the 146 patients with accurate transfusion data, it became evident that patients who received more than 5 pretransplant transfusions seldom developed greater than or equal to 50% PRL posttransplantation (P less than 0.001). Only 12% of patients receiving more than 5 pretransplant transfusions developed greater than or equal to 50% PRL, whereas 50% of patients with minimal pretransplant transfusions developed greater than or equal to 50% PRL. This protective effect of pretransplant transfusions was seen even in recipients receiving 3 and 4 HLA-A,B mismatched kidneys (P less than 0.01). The reason for this apparent protective effect is not clear from our data; it could be explained either on the basis of a selection process (i.e., exclusion of high responders pretransplant) or by suppression of the immune system. Nonetheless, these observations warrant attention, because the protective effect may be useful in preventing development of high PRL posttransplant in the event of a rejection.     

The use of cyclosporine in living-related renal transplantation. Donor-specific hyporesponsiveness and steroid withdrawal

Fourteen HLA-identical (HLA-ID) and 62 haploidentical (HP-ID) living-related donor (LRD) renal allograft recipients were transplanted using cyclosporine (CsA) and prednisone immunosuppression. No patients were preconditioned with pretransplant blood transfusions (third-party or donor-specific)--and, therefore, none were sensitized to their donor. Patient 93% (13/14) and graft 93% (13/14) survival for the HLA-ID patients is not significantly different (P greater than .1) compared with patient 98% (61/62) and graft 91% (56/62) survival in the HP-ID patients, with a mean follow-up of 16.3 (8-30) and 14.7 (2-35) months, respectively. A significant difference was noted in the incidence of treated rejection episodes (0% vs. 31%, P less than .01) and the mean serum (mg/dl) creatinine (1.37 vs. 1.71, P less than .05) at 18 months between the HLA-ID and the HP-ID and HP-ID recipients, respectively. Ten of 22 HP-ID recipients demonstrated donor-specific mixed lymphocyte culture hyporesponsiveness one year posttransplant that may have been due to the emergence of monocytoid suppressor cells. Nine of these HP-ID and seven HLA-ID recipients were subjected to a protocol of steroid withdrawal. Eleven of these patients are currently on CsA monodrug therapy and two are on alternate-day steroids from 9-18 months after discontinuation of prednisone. These findings suggest that CsA is an effective steroid-sparing agent in LRD renal transplantation that diminishes the frequency of treated rejection episodes and may permit monodrug therapy in selected individuals.     

Possible contribution of pretransplant immune responder status to renal allograft survival differences of black versus white recipients.

Black end-stage renal disease patients may present as an immunologically higher-risk group for renal allograft transplantation than white ESRD patients. To test this hypothesis, we correlated graft survivals in 124 black and 241 white cyclosporine-prednisone-treated primary cadaveric renal allograft recipients with pre-Tx nonspecific immune responder status (strong vs. weak immune responders), donor-recipient-specific MLC responsiveness, HLA match, and blood transfusion (BT) history. One-, 2- and 3-year patient survival rates of 95%, 94%, and 94% were identical for both groups. However, the 1-, 2-, 3-year graft survival rates for white recipients of 82%, 79%, and 75% were significantly higher than the 70%, 62%, and 55% rates for black recipients (P less than 0.01 for each, respectively). Pre-Tx nonspecific immune response values for blacks were significantly (P less than 0.01) higher than for whites (38% vs. 28% for active T cell; 1.8 vs. 1.3 for TH:TS ratio; 28,581 c.p.m. vs. 14,870 c.p.m. for spontaneous blastogenesis; and a stimulation index (SI) of 34 vs. 20 for panel mixed lymphocyte culture). Additionally, the specific recipient-donor MLC (SI) for black recipients was significantly greater than the specific recipient-donor MLC for white recipients (MLC SI of 40 vs. 18, P less than 0.01). Blacks present as pre-Tx strong immune responders with a greater frequency than whites (90% vs. 66%, P less than 0.01). Moreover, black strong responders experience a poorer 1-year graft survival than white strong responders (67% vs. 80%, P less than 0.01). Even though the pre-Tx BT histories of white and black ESRD patients studied herein were comparable, the immunoregulatory effect of pre-Tx BT was different in white vs. black patients. A significant reduction in TH:TS ratio was observed when comparing 0 vs. 1-4 pre-Tx white patient BT groups, whereas significant changes in TH:TS ratios were not observed until after comparing 0 vs. greater than or equal to 5 pre-Tx black patient BT groups. HLA matching and pre-Tx BT had no impact on improving the graft survivals of these CsA-Pred-treated white or black recipients. These data, therefore, support the hypothesis that black recipients present as an immunologically higher-risk group than white recipients.     

Kidney transplantation by use of splenectomy and transfusions, cadaver haplotype matching, suppressor cell assays, and T-cell monitoring

We attempted to modulate several determinants of the host immunologic profile to improve kidney transplant survival: (1) genotype matching of the cadaver donor with the recipient, (2) assessment in recipients of living related donors (LRD) for predisposition to generate suppressor cells in mixed lymphocyte culture (MLC), (3) pretransplant splenectomy and transfusions, and (4) posttransplant immunologic monitoring. Between January, 1979, and July, 1980, 48 primary renal transplants were performed and followed up between 6 and 24 months. Pretransplant splenectomy was performed, and transfusions were administered in 38 of 48 and 48 of 48 patients, respectively. Donors and recipients of 10 of 11 cadaveric transplants were genotyped and selected for one HLA haplotype identity. All 10 proved to also be one DR antigen matches. There were no cadaveric kidney losses, but one surgical antibody to T cell subtest were used to modulate rejection therapy. The LRD group (n = 37) included 13 HLA-identical, seven haploidentical low MLC reactors, and 17 haploidentical high MLC reactors. Three deaths occurred (diabetes and myocardial infarction, stroke, and pancreatitis). A three-component coculture assay was used in the LRD group before transplantation to determine the capacity to generate specific and nonspecific MLC suppressor cells. Suppressor cells were seen in 17 patients given standard immunosuppression postoperatively without rejection episodes. However, in 20 patients incapable of generating suppressor cells, seven biopsy-proved rejection episodes occurred. There were no kidney losses, with 44 of 48 surviving recipients demonstrating normal renal function.     

The effects of perioperative portal venous inoculation with donor lymphocytes on renal allograft survival in the rat. I. Specific prolongation of donor grafts and suppressor factor in the serum

In order to investigate the in vivo functional role of the liver in the immune responses in organ transplantation, effects of perioperative portal venous p.v. administration of donor lymphocytes on renal allograft survival were tested in the rat kidney transplant model. Donor lymphocytes were prepared from BN (BN, RT-1n) or third-party DA (RT1a) rat spleens and lymph nodes and injected p.v. or intravenously to Lewis (LEW, RT-1l) hosts on the day of transplantation (day 0). Untreated LEW hosts rejected BN renal grafts at 7.8 +/- 0.6 days (n = 10). Intravenous administration of 1 x 10(8) BN cells to LEW hosts on day 0 caused a slight, but not significant, prolongation of renal allograft survival (MST = 9.5 +/- 3.0 days, n = 13, NS), whereas portal venous inoculation of 1 x 10(8) BN cells on day 0 remarkably prolonged renal graft survival to 22.2 +/- 5.3 (n = 10, P less than 0.01). The prolongation of graft survival was antigen-specific; the administration of 1 x 10(8) DA cells p.v. to LEW hosts did not prolong the survival of BN renal grafts (MST = 7.4 +/- 0.8, n = 5). Spleen cells from p.v. treated LEW hosts 10 days after transplantation had no suppressor effect on the one-way MLC reaction of normal LEW responder cells toward donor BN or third-party DA stimulators. On the other hand, when serum from p.v.-treated LEW hosts was added to MLC at a concentration of 3 per cent of total volume, it suppressed the MLC reaction toward donor BN cells by 71.6 per cent, but not toward third-party DA stimulators (-8.5 per cent suppression, NS). Histological examination of p.v.-treated LEW hosts at 10 days after transplantation revealed that the liver had normal lobular architecture without expansion of portal tracts and infiltration of inflammatory cells. On the other hand, the transplanted kidney demonstrated a moderate mononuclear cell infiltration around the artery without an interstitial hemorrhage. Moreover, adoptive transfer of the serum from p.v.-treated LEW rats into the virgin secondary LEW hosts significantly prolonged the graft survival of BN kidneys from 7.8 days to 18.9 +/- 5.5 days (P less than 0.01), but not third-party DA graft survivals (MST = 7.5 +/- 0.6 days), indicating that an antigen-specific tolerogenic factor was released into the circulation through the process of allogeneic cells in the liver.     

预防预致敏受者尸体肾移植术后急性排斥反应的临床研究

目的 探讨HLA配型及新型免疫抑制剂治疗方案对预防致敏患者肾移植术后急性排斥反应的影响.方法 实验组选择46例术前致敏患者(术前PRA>10%),对照组选择同期705例未致敏患者(术前PRA<10%),实验组患者均采用诱导治疗(ATG 100 mg/d,5～7 d)+三联免疫抑制剂维持治疗方案(FK506+MMF+激素),比较两组间患者术后急性排斥反应发病率、移植肾功能延迟恢复比例、移植肾/患者一年存活率,同时分析HLA配型对移植肾急性排斥反应的影响.结果 实验组与对照组急性排斥反应的发病率分别为30.43%和19.57%(P<0.05);移植肾功能延迟恢复发病率分别为60.86%和11.87%(P<0.01).患者一年存活率分别为95.65%和98.44%,一年移植肾存活率分别为93.48%和96.88%;一年时平均血肌肝分别为130 mmol/dL和125 mmol/dL,差异无统计学意义.实验组患者HLA相配率(4.2)明显高于对照组患者(2.8)(P<0.05).实验组中HLA配型2-4错配的患者与0-2错配患者的急性排斥反应发病率有显著性差异,高度致敏患者(移植术前PRA>50%)急性排斥反应发病率较低度致敏患者(PRA 10%～20%)发病率高,移植术后PRA水平持续升高者更容易出现急性排斥反应.结论供、受者之间良好的HLA配型及采用新型免疫抑制药物治疗方案,对预防及减轻致敏患者移植术后急性排斥反应疗效确切.     

The impact of pretransplant cytomegalovirus infection on acute renal allograft rejection

BACKGROUND: The role of cytomegalovirus (CMV) infection in renal allograft rejection remains controversial; moreover, there are few studies on pretransplant infections. This study sought to investigate whether pretransplant CMV infections had negative effects on acute rejection episodes (ARE) and to evaluate the effect of preemptive treatment. METHODS: This retrospective single-center study of 416 transplant recipients from October 1, 2000 to September 1, 2003 had CMV infections diagnosed by CMV antigenemia tests. The incidences of ARE were compared between CMV-infected and noninfected groups. Risk factors for ARE were analyzed. Based on preemptive treatment, pretransplant CMV-infected recipients were divided into ganciclovir-treated and nontreated groups and the incidence of ARE was compared between the two groups. RESULTS: One hundred eighty four recipients had CMV infections pretransplant; the infection rate was 44.2%. Fifty five recipients had ARE among the pretransplant CMV-positive group, which was significantly higher than that in the noninfected group (29.9% vs 19.5%, P = .014). But the rejection subgroups and renal function recovery had no significant differences. While the presence of pretransplant infection was an independent predictor of ARE (RR = 1.807), severity showed no significant impact on ARE. Among 184 pretransplant CMV infection recipients, the incidences of ARE were 14.3% and 18.0% in ganciclovir-treated versus nontreated patients, respectively (P = .650). CONCLUSIONS: Pretransplant CMV-positive recipients were at greater risk of ARE. Pretransplant CMV infection was an independent risk factor for ARE. Preemptive antiviral treatment did not show protective effects against ARE related to CMV infection-mediated immunological injuries.     

Adverse presensitization to renal transplants. Detection by utilization of a D locus antigen-defined lymphoblastoid cell panel as targets in antibody-dependent cell-mediated cytotoxicity assays.

Sera obtained before transplantation from 52 consecutive renal allograft recipients were tested for antibody-dependent cell-mediated cytotoxicity (ADCC) and for complement-dependent cytotoxic antibodies (CDC). A D locus antigen-defined lymphoblastoid cell panel (B lymphoblastoid cell panel) was used as targets for the ADCC, and a peripheral blood lymphocyte (PBL) panel from 40 donors was used as targets for the CDC. Of the 343 ADCC assays, 118 of 168 performed with pretransplant sera from 24 recipients with early graft loss were positive, whereas only 81 of 175 performed with pretransplant sera from 25 recipients with a successful graft outcome were positive (P less than 0.001). A significantly greater degree of presensitization to the B lymphoblastoid cell panel was found in the group that lost their grafts as compared to the group with successful grafts (69% versus 49%, P less than 0.001). Sera from all six recipients with hyperacute rejection were positive in the ADCC before and after absorption with pooled platelets. In contrast, pretransplant CDC results were not predictive of ultimate graft outcome. Utilizing any level of cytotoxicity against the PBL panel as an index of adverse presensitization, no significant correlation between pretransplant CDC results and graft outcome was observed. These results suggest a prognostic role for ADCC using a B lymphoblastoid cell panel as targets to screen and identify high-risk potential graft recipients.     

Kidney transplantation in rhesus monkeys. Matching for D/DR antigens, pretransplant blood transfusions, and immunological monitoring before transplantation

The effect of matching for D/DR antigens and of three pretransplant blood transfusions on kidney allograft survival was investigated in unrelated rhesus monkeys treated with standard immunosuppression. A control group consisting of host-donor combinations mismatched for one or two DR antigens (mixed lymphocyte culture (MLC) positive) and not receiving transfusions showed a MST of 13 +/- 1.2 days with a range from 9 to 22 days. The administration of pretransplant blood transfusions led to a MST of 28 +/- 5.4 days with 5 of 12 animals showing survival times of more than 22 days (i.e., a bimodal distribution of survival times). Recipients matched with their donors for two DR antigens and given transfusions showed an even better MST of 39 +/- 4.0 days. Under these conditions, MLC-negative combinations fared slightly better than MLC-positive ones: only 1 of 10 animals showed a survival time of less than 22 days and kidney function in the first weeks after transplantation was significantly better. When mixed lymphocyte reactions (MLC reactivity) between host and donor before and after the transfusions were compared, it was possible to predict to some extent the eventual fate of an allograft: increased mixed lymphocyte reaction predicted relatively short survival times, decreased mixed lymphocyte reaction relatively long ones (P less than 0.01).     

Increased serum beta 2 microglobulin during rejection, cyclosporine-induced nephrotoxicity, and cytomegalovirus infection in renal transplant recipients

In 83 renal transplant recipients, serum beta 2 microglobulin (beta 2m) levels were significantly elevated during pretransplant uremia, rejection, cyclosporine-induced nephrotoxicity, and infections. In patients with normal serum creatinine, 74% had elevated serum beta 2m levels. None of the cyclosporine-treated patients had normal levels of beta 2m. Patients with stable renal allograft function receiving cyclosporine showed significantly higher serum beta 2m (P less than 0.001) and serum creatinine (P less than 0.01) levels than azathioprine treated patients. Patients with an irreversible rejection showed significantly higher serum concentrations of beta 2m than patients experiencing a reversible rejection (P less than 0.001). During cytomegalovirus (CMV) infection the serum beta 2m levels were elevated compared with other infections (P less than 0.001), while the serum creatinine was not. However, infected patients had higher serum levels of beta 2m and creatinine than patients with stable renal allograft function (P less than 0.001). Serum beta 2m may therefore be useful in the early diagnosis of CMV infection. To conclude, serum beta 2m levels cannot distinguish between rejection, cyclosporine nephrotoxicity, or infection.     

Excess risk of renal allograft loss associated with cigarette smoking.

BACKGROUND: Cigarette smoking contributes to a number of health-related problems, but its impact on renal transplant survival beyond accelerated patient death is unclear. METHODS: We performed a cohort study of 645 adult renal allograft recipients from 1985 to 1995 to evaluate the relationship between smoking and graft outcome. RESULTS: Twenty-four percent of recipients (156/645) were smokers at the time of transplant evaluation. Of these, 90% continued to smoke after transplantation. Pretransplant smoking was significantly associated with reduced overall graft and death-censored graft survival. Patients who were smokers at the time of pretransplant evaluation had kidney graft survival of 84%, 65%, and 48% at 1, 5, and 10 years, respectively, compared with graft survival in nonsmokers of 88%, 78%, and 62% (P=0.007). Pretransplant smoking adversely affected death-censored graft survival in recipients of cadaveric (P=0.02) and of living donor kidneys (P=0.02). Reduced graft survival in pretransplant smokers could not be accounted for by differences in rejection (64% vs. 61%, P=0.35). In a multivariate analysis, pretransplant smoking was associated with a relative risk of 2.3 for graft loss. Among patients with a smoking history before transplantation, death-censored graft survival was significantly higher for those who quit smoking before transplant evaluation. CONCLUSIONS: Cigarette smoking before kidney transplantation contributes significantly to allograft loss. The effect of smoking on graft outcome is not explained by increases in rejection or patient death. Smoking cessation before renal transplantation has beneficial effects on graft survival. These effects should be emphasized to patients with end-stage renal disease who are considering renal transplantation.     

Identification of natural suppressor cells in long-term renal allograft recipients.

We have previously reported an abnormal expansion of CD3+Leu7+ (CD57+) large granular lymphocytes in long-term renal allograft recipients. These cells lacked NK activity, T-helper activity and did not respond to T cell mitogens. The following studies were done in order to further define the functional characteristics of these cells. We sorted CD3+Leu7+ T cells from the peripheral blood of 45 recipients (all with good renal allograft function), and found that these cells suppress mixed lymphocyte culture responses and pokeweed mitogen-induced IgG secretion in a non-genetically restricted manner. PWM-induced IgG secretion assays are suppressed by 60-100%, and MLC responses are suppressed by 20-85% at a ratio of 1:10 CD3+Leu7+ cells to responder/effector cells. Supernatants from CD3+Leu7+ cell cultures are also suppressive. On the other hand, unsorted cells and non-CD3+Leu7+ sorted cells either enhance responses or produce less than 10% suppression under the same conditions. Patients who were tested more than once showed a relatively stable percentage and suppressive effect of their CD3+Leu7+ cells over an interval of 6-12 months. These nonspecifically suppressive CD3+Leu7+ large granular lymphocytes are similar in many ways to the natural suppressor cells that have been identified in hematopoietic tissues, in graft-vs.-host disease, and in the lymphoid organs of neonates.     

Glomerular function, structure, and number in renal allografts from older deceased donors

The 5-yr survival rate of renal allografts is significantly lower for grafts from older deceased donors than from younger deceased donors. For evaluation of the potential contribution of renal senescence in this shortened graft survival, glomerular function and structure were analyzed in allografts from deceased donors older than 55 yr ("aging") or younger than 40 yr ("youthful"). Aging donors had a significantly higher prevalence of sclerotic glomeruli (P < 0.002), and their nonsclerotic glomeruli tended to be larger, had a larger filtration surface area (P = 0.02), and had a higher single-nephron ultrafiltration coefficient (K(f); P = 0.07), suggesting a compensatory response to functional loss of glomeruli. After serum creatinine reached a stable nadir in the transplant recipients, GFR and its hemodynamic determinants were evaluated and the whole allograft K(f) was computed. Compared with the allografts from youthful donors, allografts from aging donors exhibited a 32% lower GFR, which was exclusively attributable to a 45% reduction in allograft K(f) (both P < 0.001). In addition, the number of functioning glomeruli per allograft was profoundly lower in grafts from aging donors than from youthful donors (3.6 +/- 2.1 x 10(5) versus 8.5 +/- 3.4 x 10(5); P < 0.01), and this could not be explained by the relatively modest 17% prevalence of global glomerulosclerosis in the aging group. The marked reduction in overall glomerular number in many aging donors may lead to a "remnant kidney" phenomenon, potentially explaining the shorter mean survival of these allografts.     

Significance of mixed lymphocyte culture (MLC) in renal transplants from living donors

Results of MLC were correlated with kidney-graft survival of recipients of living related donor. The 56 patients tested by MLC were divided into two groups according as the stimulation index was more or less than 5. In 20 of these patients transplanted, renal allograft survival correlated better with low stimulation in MLC, suggesting more histocompatibility.     

Synergistic effect of donor-specific blood transfusion and a short course of deoxyspergualin in rat kidney transplantation

Deoxyspergualin (DSG), an analogue of spergualin produced by B. laterosporus, has a strong immunosuppressive effect in various transplantation models. We have investigated the mechanism of donor-specific prolongation of survival time in rat kidney grafting by donor-specific blood transfusion (DST) and a short course of DSG. Lewis (LEW) kidney allografts were transplanted into fully allogeneic BN rats. Fresh, whole LEW blood 1.0 ml, was injected i.v. into BN rats 2 days prior to transplantation. Then, DSG, 6 mg/kg per day, was administered by i.m. injection on days 0, 1, and 2 after transplantation. The recipients were divided into five groups: group 1 (n=6) no treatment: group 2 (n=6) DST only; group 3 (n=7) DSG only; group 4 (n=7) DST and DSG; and group 5 (n=6), third party (ACI rats) blood transfusion and DSG. Lymphocytes (cervical lymph nodes) and serum were harvested from BN recipients on day 7 postgrafting. For suppressor cell assays, lymphocytes from BN recipients in each group were added as a third cell to the mixed lymphocyte reaction (MLC) between nontransplanted BN lymphocytes (responder) and LEW or other third party (PVGC, ACI, WKA rats) lymphocytes (stimulator). Antidonor lymphocytotoxic antibody (ADLA) was checked by microcytotoxicity assays. Median survival times (MST) for each group were: group 1, 10 days; group 1, 10 days; group 3, 13 days; group 4, 75 days; and group 5, 13 days. Remarkable prolongation of MST was only noted in group 4. In the suppressor cell assay, group 4 showed significant suppression (40%; P<0.05); the other groups did not show any suppression. This suppressive activity in group 4 was effective only during the MLC between BN and LEW, not during the MLC of third party-BN combinations. Thus, suppressor cells from DST/DSG-treated BN recipients appear to be donor-specific. In the microcytotoxicity assay, the only group that showed any ADLA was group 2, which was not treated with DSG. These results clearly show that both induction of donor-specific suppressor cells and inhibition of ADLA production are associated with the remarkable donor-specific prolongation of kidney allograft survival in DST/DSG-treated recipients.     

Nature of the suppressor cells mediating prolonged graft survival after administration of extracted histocompatibility antigen and cyclosporine

Antigen-specific suppressor T cells are induced by donor histocompatibility antigen extracted from spleen cells with 3M KCl combined with cyclosporine (Ag-CsA). A single i.v. injection of 5 mg 3M-KCl-extracted donor Buffalo (Buf, RT1b) antigen (Ag) combined with a three day course of CsA prolonged renal allograft survival in Wistar-Furth (WFu, RT1u) hosts to a greater extent (MST 26.5 days) than CsA alone (MST 11.8 days). Peripheral blood lymphocytes (PBL) or spleen cells harvested from Ag-CsA-treated recipients ten days after transplantation inhibited the mixed lymphocyte reaction (MLR) between normal responder WFu cells and irradiated Buf cells (55.6% and 64.4% suppression, respectively, P less than 0.025), but not third-party Brown-Norway (BN, RT1n) stimulator cells (13.6% and -18.3% suppression, respectively, NS). The suppressor effect was not mediated by cytolytic cells; there was neither primary nor secondary cytolytic activity against 51Cr-labeled Con-A blastoid Buf cells. The suppressor cells were neither adherent to plastic dishes nor to nylon-wool columns. PBL irradiated with 800 rads, but not 1500 rads, suppressed the MLR. A single injection of cyclophosphamide (CY, 25 mg/kg) seven days after transplantation abrogated the suppression induced by Ag-CsA treatment. Moreover, PBL from Ag-CsA recipients failed to suppress the MLR, if depleted either of all T cells by treatment with monoclonal antibody (Mab) W3/13 HLK (pan T cells; % suppression -15.8), or of cytotoxic/suppressor cells with Mab OX-8 (-19.3% suppression) together with rabbit antimouse immunoglobulin and complement. On the other hand, PBL treated with the Mab W3/25 (helper) showed suppressor cell activity (+56.4%, P less than 0.001) similar to untreated cells (62.4%, P less than 0.001). Moreover, adoptive transfer of suppressor T cells purified from pooled lymphocytes by rosetting using Mab significantly prolonged the survival of donor-specific, but not third-party, test grafts in naive secondary hosts. Thus, these studies demonstrated antigen-specific suppressor T cells mediate the long-term unresponsiveness induced by the Ag-CsA regimen.     

Adverse influence of recipient lymphoid resistance to in vitro immunosuppression on the outcome of kidney transplants

The study investigated whether preoperative in vitro sensitivity of lymphocytes from potential renal transplant recipients could identify patients at increased risk of acute rejection following transplantation and immunosuppression with cyclosporine, azathioprine, and prednisolone. Mixed lymphocyte culture responses were measured preoperatively in the presence of methylprednisolone, CsA, and antithymocyte globulin, and without immunosuppressive agents in 50 transfused recipients of primary cadaver renal transplants. Patients were classified as sensitive if all three immunosuppressive agents produced more than 50% inhibition of their MLC responses, and as resistant if one or more agents failed to produce 50% inhibition. All patients received postoperatively a standardized triple immunosuppressive regimen. Acute rejection was confirmed histologically and treated with Pred with or without ATG or monoclonal antibody OKT3. A total of 29 patients (58%) were sensitive and 21 (42%) were resistant; 4 patients were resistant to 3 agents, 5 were resistant to MP and ATG, 6 were resistant to MP and CsA, and 6 were resistant to MP alone. Sensitive and resistant groups did not differ in age, sex, transfusion history, HLA A, B and DR mismatches or duration of follow-up. The resistant group had a higher rate of graft loss from acute rejection (chi 2 = 6.0, d.f. = 1, P less than 0.02), more episodes of acute rejection (chi 2 = 8.7, d.f. = 3, P less than 0.05), and a higher proportion of patients in whom reflux nephropathy was the cause of renal failure (chi 2 = 18.3, d.f. = 1, P less than 0.001). The resistant group also had a higher proportion of highly sensitized patients and higher serum creatinine concentrations than the sensitive group, although the differences did not reach statistical significance. The study indicates that patients at high risk of acute rejection of renal allografts can be identified by a pretransplant in vitro assay, a finding that could influence recipient selection and immunosuppression.