Immunomagnetic t-lymphocyte depletion (ITLD) of rat bone marrow using OX-19 monoclonal antibody

Graft versus host disease (GVHD) may be abrogated and host survival prolonged by in vitro depletion of T lymphocytes from bone marrow (BM) prior to allotransplantation. Using a mouse anti-rat pan T-lymphocyte monoclonal antibody (0×19) bound to monosized, magnetic, polymer beads, T lymphocytes were removed in vitro from normal bone marrow. The removal of the T lymphocytes was confirmed by flow cytometry. Injection of the T-lymphocyte-depleted bone marrow into fully allogeneic rats prevents the induction of GVHD and prolongs host survival. A highly efficient technique of T-lymphocyte depletion using rat bone marrow is described. It involves the binding of OX-19, a MoAb directed against all rat thy-mocytes and mature peripheral T lymphocytes, to monosized, magnetic polymer spheres. Magnetic separation of T lymphocytes after mixing the allogeneic bone marrow with the bead/OX-19 complex provides for a simple, rapid depletion of T lymphocytes from the bone marrow. In vitro studies using flow cytometry and the prevention of GVHD in a fully allogeneic rat bone marrow model have been used to demonstrate the effectiveness of the depletion procedure. © 1989 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted

Current status of intestinal transplantation in children

Purpose: A clinical trial of intestinal transplantation (Itx) under tacrolimus and prednisone immunosuppression was initiated in June 1990 in children with irreversible intestinal failure and who were dependent on total parenteral nutrition (TPN). Methods: Fifty-five patients (28 girls, 27 boys) with a median age of 3.2 years (range, 0.5 to 18 years) received 58 intestinal transplants that included isolated small bowel (SB) (n = 17), liver SB (LSB) (n = 33), and multivisceral (MV) (n = 8) allografts. Nine patients also received bone marrow infusion, and there were 20 colonic allografts. Azathioprine, cyclophosphamide, or mycophenolate mofetil were used in different phases of the series. Indications for Itx included: gastroschisis (n = 14), volvulus (n = 13), necrotizing enterocolitis (n = 6), intestinal atresia (n = 8), chronic intestinal pseudoobstruction (n = 5), Hirschsprung's disease (n = 4), microvillus inclusion disease (n = 3), multiple polyposis (n = 1), and trauma (n = 1). Results: Currently, 30 patients are alive (patient survival, 55%; graft survival, 52%). Twenty-nine children with functioning grafts are living at home and off TPN, with a mean follow-up of 962 (range, 75 to 2,424) days. Immunologic complications have included liver allograft rejection (n = 18), intestinal allograft rejection (n = 52), posttransplant lymphoproliferative disease (n = 16), cytomegalovirus (n = 16) and graft-versus-host disease (n = 4). A combination of associated complications included intestinal perforation (n = 4), biliary leak (n = 3), bile duct stenosis (n = 1), intestinal leak (n = 6), dehiscence with evisceration (n = 4), hepatic artery thrombosis (n = 3), bleeding (n = 9), portal vein stenosis (n = 1), intraabdominal abscess (n = 11), and chylous ascites (n = 4). Graft loss occurred as a result of rejection (n = 8), infection (n = 12), technical complications (n = 8), and complications of TPN after graft removal (n = 3). There were four retransplants (SB, n = 1; LSB n = 3). Conclusions: Intestinal transplantation is a valid therapeutic option for patients with intestinal failure suffering complications of TPN. The complex clinical and immunologic course of these patients is reflected in a higher complication rate as well as patient and graft loss than seen after heart, liver, and kidney transplantation, although better than after lung transplantation

Reversal of graft-versus-host disease with infusion of autologous bone marrow

Graft-versus-host disease (GVHD) remains a major complication of bone marrow transplantation. This report describes reversal of GVHD by infusion of stored recipient bone marrow following combined liver-bone marrow allotransplantation. Graft-versus-host disease developed at the end of the first postoperative week. The skin involvement progressively spread to approximately 80% of the body surface and was not affected by modification of the immunosuppressive treatment. On the 42nd and 43rd postoperative day 1.23 × 108 and 1.6 × 108 autologous bone marrow cells per kg of recipient body weight were infused. The skin rush began to dramatically improve and resolved within 2 wk from the autologous marrow infusion. Autologous bone marrow storage previous to allogeneic bone marrow transplantation for tolerance induction could constitute a safety net in case of occurrence of GVHD. © 1994

Immunomodulation for intestinal transplantation by allograft irradiation, adjunct donor bone marrow infusion, or both.

BACKGROUND: The passenger leukocytes in the intestine have a lineage profile that predisposes to graft-versus-host disease (GVHD) in some animal models and have inferior tolerogenic qualities compared with the leukocytes in the liver, other solid organs, and bone marrow. Elimination by ex vivo irradiation of mature lymphoid elements from the bowel allografts is known to eliminate the GVHD risk. We hypothesized that infusion of donor bone marrow cells (BMC) in recipients of irradiated intestine would improve tolerogenesis without increasing the risk of GVHD. METHODS: Orthotopic small intestine transplantation was performed with the GVHD-prone Lewis (LEW)-to-Brown Norway (BN) combination and the reverse GVHD-resistant BN-to-LEW model under a short course of tacrolimus treatment (1 mg/kg/day, days 0-13, 20, 27). Grafts were irradiated ex vivo, using a 137Cs source. In selected experimental groups, donor BMC (2.5 x 10(8)) were infused on the day of small intestine transplantation. RESULTS: The unmodified LEW intestine remained intact, whether transplanted alone or with adjunct donor BMC infusion, but all of the BN recipients died of GVHD after approximately 2 months. Intestinal graft irradiation (10 Gy) effectively prevented the GVHD and prolonged survival to 92.5 days, but all of the BN recipients died with chronic rejection of the LEW grafts, which was prevented by infusion of adjunct donor BMC without causing GVHD. In the GVHD-resistant reverse strain direction (BN-->LEW), all intestinal recipients treated for 27 days with tacrolimus survived > or =150 days without regard for graft irradiation or adjunct BMC, but chronic rejection was severe in the irradiated intestine, moderate in the unaltered graft, and least in the irradiated intestine transplanted with adjunct BMC. Mild arteritis in the 150 day allografts of both strain combinations (i.e., LEW--> BN and BN-->LEW) may have been irradiation associated, but this was prevented when weekly doses of tacrolimus were continued for the duration of the experiment rather than being stopped at 27 days. CONCLUSIONS: Recipients are protected from GVHD by irradiating intestinal allografts, but the resulting leukocyte depletion leads to chronic rejection of the transplanted bowel. The chronic rejection is prevented with adjunct donor BMC without causing GVHD. Although application of the strategy may be limited by the possibility of radiation injury, the results are consistent with the paradigm that we have proposed to explain organ-induced graft acceptance, tolerance, and chronic rejection

minimally invasive video assisted parathyroidectomy: multiistitutional study

Unilateral and minimally invasive parathyroidectomies with endoscopic and video-assisted technique have been introduced. Most of these procedures utilize preoperative localization and intraoperative monitoring of parathyroid hormone. There are only a few reports on these procedures. The objective of this study was to evaluate video-assisted parathyroidectomy (MIVAP) for surgery in patients with primary hyperparathyroidism (pHPT). From February 1997 to June 1999 a series of 123 consecutive patients with pHPT at four surgical centers were evaluated. The patients' ages ranged from 18 to 77 years (median 50 years). Preoperatively, sestamibi scintigraphy and ultrasonography for localization were performed for all patients. Selection criteria for a MIVAP procedure excluded patients with negative localization, suspicion of multiglandular disease (MGD) or thyroid malignancy, a large thyroid mass, and prior surgery or irradiation to the neck. MIVAP was performed with a 1.5 cm suprasternal incision; the operation was then done through this incision with a 30 degree 5 mm endoscope and microsurgical instruments with brief CO 2 insufflation for adenoma identification. We then proceeded with an open technique through the small incision under video-assistance. Intraoperative monitoring of intact parathyroid hormone (iPTH) assays was used in ali patients. Among the 123 patients in whom MIVAP was attempted, the procedure was accomplished in 109 (89%). Conversion to conventional cervicotomy was required in 14 (11%) patients because of failed localization, failure of the iPTH level to fall appropriately, or technical problems. There was no persistent or recurrent HPT during the 3 to 12-month follow-up. Oral calcium replacement for symptomatic hypocalcemia postoperatively was given in 7 (6%) cases. A unilateral transient laryngeal nerve palsy, resolving within 6 months postoperatively, occurred in two (2%) patients. The median hospital stay was 1.5 days (range 0.5-5.0 days). This study showed the feasibility of MIVAP as an alternative surgical treatment for pHPT in a selected group of patients. Further studies are necessary to evaluate the efficacy and rationale of MIVAP compared to other techniques for parathyroidectomy in pHPT patients