Analysis of T Lymphocytes Cloned from Rejected Kidney Allograft: High Frequency of Cytotoxic T Cell Precursor

A high proportion of CD8 positive cells and inverted CD4/CD8 ratio were found in peripheral blood mononuclear cells and in freshly isolated kidney-graft infiltrating cells in two patients who underwent irreversible acute rejection.

Seventy seven T cell clones were generated from the T cell blasts infiltrating rejected kidney allografts. The majority of T cell clones obtained showed CD8 phenotype in accordance to uncloned graft infiltrating cells. All clones (both CD8 and CD4) displayed cytolytic activity evaluated by lectin-dependent cell-mediated cytotoxicity and natural killer (NK) activities. None of the clones presented lymphokine activated killer phenomenon.

These data suggest that the graft infiltrate is characterized by T cell clones with cytolytic potential and that these T cell clones may be responsible for the killing of graft cells by a CTL or NK type mechanism.

Cytokine level modifications: molecular adsorbent recirculating system versus standard medical therapy

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is a systemic inflammatory reaction, which is characterized by a predominantly proinflammatory cytokine profile, causing the transition from stable cirrhosis to ACLF. The aim of the present study was to evaluate the changes in several cytokines associated with inflammatory liver disease and liver regeneration among 15 ACLF patients treated with the Molecular Adsorbent Recirculating System (MARS) compared with 15 patients treated with standard medical therapy (SMT). The subjects showed various disease etiologies but similar values for Model End-stage Liver Disease scores.

METHODS

In the MARS group, 15 (10 male and 5 female) patients were treated with MARS (Gambro). The number of MARS applications was nine; the length of applications was 8 hours. In the SMT group; 15 (10 male and 5 female) patients were treated with SMT. The patients were monitored for 30 days from inclusion with a survival follow-up at 3 months. Statistical results were calculated with SPSS14.0 (SPSS Inc, Chicago, Ill). A P < .07 was considered significant.

RESULTS

In the MARS group, we observed significant changes in the levels of Interleukin (IL)-6, IL-1, IL-10, and tumor necrosis factor (TNF)-alpha in association with improved hepatocyte growth factor. Patient survival at 3 months was 60%. The SMT group showed only a significant change in TNF-alpha (P = .03). Patient survival at 3 months was 30%.

CONCLUSION

The MARS liver support device corrected pathophysiologies of ALF and may be used to enhance spontaneous recovery or as a bridge to transplantation.

Alloantibodies and outcomes of deceased donor kidney allografts

Analysis of the anti-HLA antibody status of 100 recipients of kidneys from deceased donors demonstrated that presensitization and the development of alloantibodies after transplantation are associated with the development of antibody mediated as well as cellular rejection. This finding indicates that the humoral arm of the immune response is also involved in cell-mediated rejection and/or that there may be a continuum between these two forms of rejection. Most episodes of rejection were successfully reversed in our population, as shown by the overall 3-year actuarial survival of 98% in nonsensitized and 91% in sensitized recipients, emphasizing the importance of comprehensive antibody studies.

Adacolumn treatment in kidney transplant patients with hepatitis C virus

INTRODUCTION

Patients who have undergone kidney transplantation and suffer from hepatitis C (HCV) cannot be treated with standard therapy (pegylated interferon combined with ribavirin) due to the risk of acute rejection. Furthermore, immunosuppressive therapy facilitates the progression of infection and chronic hepatopathies. Monocytes and macrophages are known to produce extrahepatic breeding sites that spread disease. Our aim was to reduce macrophages, granulocytes, monocytes, proinflammatory cells, and viremia levels using an extracorporeal device: Adacolumn Leukocyte Apheresis (Otzuka Electronics, Japan).

METHODS

The Adalcolumn filter is filled with 2-mm cellulose acetate beads immersed in sterile saline solution. These carriers absorb granulocytes and monocytes/macrophanges through their FCR receptors. Six patients affected by viral genotype 1b underwent five 1-hour treatments for 5 consecutive days.

RESULTS

Viremia was reduced in Patients 1, 2, 4, and 6 in association with decreased pro-inflammatory cytokine levels and a normal CD4/CD8 T-cell ratio, after 3 months. Subjects 1 and 3 showed inverted CD4(+)/CD8(+) T-cell ratios, which changed at 4-month follow-up in only patient 1. Subject 5 did not show any changes.

CONCLUSIONS

The treatment was safe without hemodynamic or infectious complications, suggesting that this method could be used in a greater number of patients to evaluate amelioration of increased viremia.

Survival in kidney transplantation from living donors: a single-center experience

BACKGROUND

Transplantation from living donors, in Italy, is still not accepted, in particular those from unrelated donors. The aim of this paper was to present the experience of one transplant center.

MATERIALS AND METHODS

Since 1982, 608 transplants were performed from living donors using cyclosporine as the main component of immunosuppressive therapy. Among those, 402 transplants were from related living donors (338 one haplotype pairs and 25 zero haplotypes pairs) and 206 from unrelated living donors (171 spouses and 35 emotionally related subjects).

RESULTS

Graft survival at 1, 5, and 10 years showed no statistically meaningful difference between the two groups. A group of 19 transplants performed in predialytic phase patients was compared with a contemporaneous group of 167 transplants performed in patients who were already receiving dialysis. These two groups did not show any statistically meaningful difference in graft survival at 1, 5, or 10 years.

DISCUSSION AND CONCLUSIONS

We think that transplants from living donors, whether related or unrelated, must always be proposed as a therapeutic option for end-stage renal disease patients, since they show an higher graft survival than that from cadaveric donors, independent of the compatibility between donor and recipient and independent of the degree of relationship of the pair. Transplantation from living donors definitely is a complementary, not substitutive, program to that from cadaveric donors, which should always be encouraged with awareness campaigns among the population and targeted programs for healthy personnel.

Detection of T suppressor cells in patients with organ allografts

Specific immunosuppression of host's immune response to donor HLA antigens has been a major goal to clinical transplantation. Recent evidence has been accumulating to show that a distinct population of T cells expressing the CD8(+) CD28(-) phenotype display suppressor function and inhibit Th activation and proliferation by modulating the APC function. To assess the presence of Ts in transplant recipient's circulation, we have developed a flow cytometry method that measures the expression of costimulatory molecules on donor APC exposed to recipient Th and Ts. Our results demonstrate that quantitation of the capacity of CD8(+) CD28(-) T cells from patient circulation to suppress the activation of costimulatory molecules (CD80, CD86) on donor APC offers a reliable tool for monitoring specific immunosuppression against the graft in solid organ transplantation.

Mechanism of liver allograft rejection: the indirect recognition pathway

Transplant rejection is mediated by the direct and indirect pathways. To explore the role of the indirect recognition pathway in the rejection of liver allografts, T cells obtained from peripheral blood were expanded in medium containing IL-2 and tested in LDA for reactivity to synthetic peptides corresponding to the hypervariable regions of the mismatched HLA-DR antigen(s) of the donor. Serial investigations of 17 recipients showed that T-cell reactivity to donor HLA-DR peptides was strongly associated with acute rejection episodes. In recipients carrying a graft that was mismatched by two HLA-DR alleles, a single donor antigen was targeted during primary rejection, although allopeptide reactivity against the second HLA-DR antigen was observed during subsequent episodes of acute rejection. The finding that allopeptide reactivity occurs early following transplantation and is predictive of rejection is consistent with the notion that processing of donor alloantigens by recipient APCs activates the indirect T-cell recognition pathway that plays a major role in initiating and amplifying allograft rejection.

[Long-term follow up of patients surgically treated for pyelo-ureteral disease by the Anderson-Hynes technique]

A series of 48 patients with hydronephrosis (mean age 31 yrs.) underwent on Anderson-Hynes pyeloplasty. Assessment was carried out in 30 pts. after a mean observation time of 90 months, with a minimum 5 years follow-up. Clinical examination, laboratory investigations, renal ultrasonography, urography and renal scan were performed pre-operatively and at follow-up. There was one patient with evidence of stenosis in the ureteropelvic junction; one patient developed urinary leakage post-operatively and required surgical correction. All patients had symptoms pre-operatively and no one had symptoms post-operatively. Four patients had calcolosis associated, postoperatively all pts. were stone free; four years later one patient developed litiasis. We observed that the results of surgical intervention in hydronephrosis are excellent especially in patients aged less than 30 years.

Immunoadsorption with protein A in humoral rejection of kidney transplants

The presence of alloantibodies may play a role in accelerated or acute humoral rejection. Different therapeutic strategies based on a removal of anti donor antibodies and prevention of their resynthesis have been used in the management of transplant rejection episodes. Immunoadsorption with staphylococcal protein A, a method to selectively remove immunoglobulin G, may represent a new treatment to reverse humoral rejection in kidney transplantation. From 1991 to January 1996, such a method was used in 23 patients in whom an acute humoral rejection developed over a mean period of 14.1 +/- 9.5 days after operation. Twenty-two patients had been transplanted from living donors and one from a cadaveric donor. The ages ranged from 23 to 58 years (mean, 34 +/- 10 years). All transplants were performed according to a negative direct crossmatch. Basic immunosuppression included cyclosporine, steroids, azathioprine, and antilymphocyte globulin or monoclonal antibodies (OKT3). Rejection was diagnosed on the basis of hematochemical tests, Doppler ultrasonography, and kidney biopsy. Only steroid and monoclonal and polyclonal antibody resistant rejections with > 165% positive direct crossmatches against the donor were treated with Protein A immunoabsorption. The procedure used is based on the treatment of 2-3 plasma volumes for the first 2 days and then every other day until a negative crossmatch is obtained, together with improvement in clinical status (mean treatments, 7.3 +/- 4.5 [range, 4-23]; mean duration of treatment, 12.3 +/- 10.2 days [range, 3-44]). From the start of treatment, azathioprine is replaced by cyclophosphamide at a dose of 1-2 mg/kg/day. During treatment, a remarkable fall in immunoglobulin G levels is achieved on the first day, whereas immunoglobulin M titers remain constant, with a slight decrease in serum albumin. Immediately after treatment, a negative crossmatch was found in 22 (95.6%) of 23 patients. In six patients (26%), graft function did not recover, and one patient (4.3%) died. Preliminary results show that immunoabsorption with staphylococcal protein A may be an effective support in the treatment of humoral acute rejection, particularly when it is performed as soon as an early diagnosis of humoral rejection is made. In fact, such treatment has a highly selective adsorption, allows treatment of large volumes of plasma, and can achieve a rapid decrease in the titer of circulating immunoglobulins.

Homing of CD4+CD56+ T lymphocytes into kidney allografts during tubular necrosis or rejection

The association between acute rejection, acute tubular necrosis, good function and relative infiltration of CD56 subsets of both CD8+ and CD4+ T cells was examined on 67 samples of graft infiltrating cells (GIC) and corresponding peripheral blood lymphocytes (PBL) obtained from renal allograft recipients. Quantification of cell subset profiles was determined by two-color flow cytometry. While a high proportion of CD4+CD56+ GIC was detected when both renal dysfunction and graft cytopathology (acute tubular necrosis or acute rejection) were present, this cell subset was undetectable in peripheral blood. In contrast the CD8+CD56+ T-cell subset was not discriminatory. The presence of CD4+CD56+ cells among freshly-isolated lymphocytes from renal allografts supports the idea that the local environment is involved in the selection of this subset, thus participating in the amplification of the immune-response. In addition, a homing of this T-cell subset into the transplanted organ may constitute an early sign of graft immunopathology.

[The evolution of immunosuppression in clinical kidney transplantation: the experience of 700 cases]

Kidney transplantation was first introduced in Italy in 1966 by the II Surgical Pathology of the University of Rome giving a great contribution to the development of the transplant surgery in this country. The authors report their 25-year experience analyzing the results obtained in more than 700 kidney allografts. A progressive refinement in the surgical transplant technique both from cadaver and live as well as clinical trials on new immunosuppressive protocols characterized their work.

Enhanced production of interferon-gamma by T lymphocytes cloned from rejected kidney grafts

Seventy-seven T cell clones were generated from cell blasts infiltrating rejected kidney allografts. All clones, either CD4 or CD8, displayed cytolytic activity evaluated by lectin-dependent cell-mediated cytotoxicity (LDCC) and natural killer activities. Furthermore, both types of clones were able to produce IFN-gamma following PHA stimulation. These data suggest that the graft infiltrate is characterized by T cell clones with cytolytic potential responsible for the killing of graft cells. The production of IFN-gamma, enhancing the class II MHC expression, may amplify the recipient immune response.

Immunological studies of renal allograft recipients treated with total lymphoid irradiation

It is well known that highly sensitized patients and/or high responders, even under CsA therapy, constitute a risk category for transplantation. Based on this evidence, in 1982, our group initiates a pilot study using total lymphoid irradiation (TLI) as a pre-transplant modulator of patient's immuno-response. TLI has been employed in 30 uremic, non diabetic, patients. During this experience the first protocol, characterized by pre-transplant TLI greater than 2,000 rads (13 pts.) and post-transplant conventional therapy, was abandoned because of the severe TLI side effects. In the second protocol TLI dose never exceeded 2,000 rads and CsA was given, at initial dose of 7-12 mg/Kg/day according to CsA blood through levels. The immunological monitoring was performed during TLI treatment and in the postoperative clinical course by cell markers profile determination and functional assays. The data obtained have demonstrated that TLI treatment causes a prolonged depression in CD4 positive cells, a predominant recovery of T suppressor population, a pronounced impairment of T functions and a development of specific unresponsiveness to donor antigens. Furthermore the TLI plus CsA protocol, showing an additive effect which steadily decreases patient immunoreactivity, a lack of side effects and a stable long term graft function seems to be a more useful method for transplantation in high-risk or in strongly immunoreactive patients.