Pretreatment of Crude Pancreatic Islets with Mitomycin C (Mmc) Prolongs Islet Graft Survival in a Xenogeneic Rat-To-Mouse Model

In this study, we examined the effect of mitomycin C (MMC) treatment on graft survival and evaluated its efficacy in immunomodulation of islet graft for transplantation. Male WS rats were used as islet donors and streptozotocin-induced diabetic C57BL/6 mice as recipients. The isolated islets were treated with MMC at concentrations of 0, 0.1, 1, 3.2, 10, 32, 100, 320, and 1000 μg/mL for 30 min, and were cultured for 20 h. Then, 300–400 islets were transplanted into the renal subcapsular space of diabetic mice. Significant prolongation of graft survival was obtained when the islets were treated with MMC at a concentration of 10, 32, or 100 μg/mL (MST 23 ± 7.4, 17.5 ± 5.4, 29.6 ± 9.7 days: p < 0.003, p < 0.012, p < 0.001, respectively, vs. 12.3 ± 2.7 days for culturing alone). Islets treated with MMC at a concentration of 320 μg/mL or more failed to restore normoglycemia in the diabetic recipient mice after transplantation. Viability of islets incubated with doses up to 100 μg/mL, assessed under the confocal microscope after propidium iodide and Hoechst 33342 staining, was maintained well comparable to that of freshly isolated islets, while those treated at 320 μg/mL was significantly decreased. Thus, a therapeutic window for MMC efficacy was found at concentrations from 10 μg/mL to 100 μg/mL. This modality is simple and effective and underlying molecular mechanisms need to be determined in the future.

[Evaluation of hepatic resection following hepatic arterial infusion chemotherapy for colorectal liver metastases]

We evaluated the significance of hepatectomy following hepatic arterial infusion (HAI) chemotherapy for colorectal liver metastases. The prognosis of 4 cases with initially resectable tumors was discouraging, indicating no benefit of preoperative HAI for resectable tumors. The 2- and 3-year survival of patients who underwent hepatectomy after downstaging by HAI of originally unresectable metastases were 100% and 67%, respectively, suggesting that hepatectomy combined with HAI is a promising modality for those patients. However, it seems that the control of extrahepatic disease and decision making for the timing for surgical therapy are issues requiring improvement.

Surgical treatment of hepatic caudate lobe metastases originating from colorectal primaries

Malignant tumor resection of the hepatic caudate lobe has recently received attention. However, there are few reports about metastatic liver tumor in the caudate lobe from colorectal carcinoma, and its clinical features still remain unknown. In this paper, three patients operated on in our institute and 15 reported cases from the published literature were analyzed in order to reveal clinical features of this disease. Many cases had advanced liver tumors, such as invasion in to major vessels at the time of operation. Isolated complete caudate lobectomy was performed in 8 patients and major hepatectomy was carried out in 6 instances. Seven cases also underwent partial resection of the inferior vena cava. Recurrence of disease was observed in 11 patients: seven cases had relapse only in the residual liver, five of whom underwent another hepatectomy. The median survival time of those patients who died was 25 months, and that of seven cases with IVC resection, 18 months. Two patients out of five who received a second hepatectomy survived for longer than 90 months. It is suggested that aggressive surgical treatment including repeated hepatectomy results in the prolongation of survival. Earlier diagnosis and surgical treatment at a more appropriate stage of the disease may further improve the survival rate.

Outcome of pancreatic cancer patients based on genetic lymph node staging

We prospectively assessed the clinical value of genetic staging of lymph node metastasis in patients with pancreatic adenocarcinoma who underwent curative surgery. K-ras gene mutations were detected in the primary tumors in 18 of 25 patients with pancreatic adenocarcinoma. Among these 18 patients, mutated K-ras gene was also found in at least one lymph node in 13 patients. Of these 13 patients, seven had no evidence of histological nodal involvement and six had histological lymph node metastasis. Although there was no significant difference in overall survival rates between the pathological node-negative and -positive patients, overall survival of the five patients with nodes-negative for the mutated K-ras gene were significantly better than that of the 13 patients with genetically metastasis-positive nodes (p<0.001). Furthermore, overall survival of the six patients with genetically metastasis-positive nodes limited to peripancreatic area was significantly better than that of seven patients with genetical metastasis in lymph nodes beyond the peripancreatic areas (p=0.018). These findings suggest that detection of K-ras gene mutations in lymph nodes may be clinically useful to assess the accurate tumor staging and to stratify the patient with pancreatic adenocarcinoma who are at high or low risk for recurrence after curative surgery.

Limited but definite efficacy of prophylactic hepatic arterial infusion chemotherapy after curative resection of colorectal liver metastases: A randomized study

BACKGROUND

Greater than 50% of patients who undergo curative resection of liver metastases from colorectal carcinoma develop recurrent disease in the residual liver. Although several studies have attempted to use hepatic arterial infusion (HAI) chemotherapy to prevent recurrence, to the authors' knowledge the efficacy of the treatment has not yet been determined.

METHODS

Nineteen patients who underwent curative hepatectomy for metastatic colorectal carcinoma randomly were assigned into the HAI group (nine patients) or the control group (ten patients). Patients in the HAI group received continuous intraarterial infusion of 5-fluorouracil (5-FU) (500 mg/day) for 4 days followed by a 3-day rest. The treatment was continued for 6 weeks.

RESULTS

The median follow-up period was 62.2 months. The recurrence was confirmed in three patients in the HAI group and in eight patients in the control group. Of these, recurrence in the remnant liver was observed in one patient and in six patients, respectively. The median disease free interval after hepatectomy was 62.6 months in the HAI group and 13.8 months in the control group. The 1-year, 2-year, and 3-year disease free survival rates were 77.8%, 77.8%, and 66.7%, respectively, in the HAI group and 50.0%, 30.0%, and 20.0%, respectively, in the control group. Significant prolongation of disease free survival was observed in the HAI group (P = 0.045). No patients in the HAI group reported any adverse effect of >/= Grade 2 (according to the National Cancer Institute Common Toxicity Criteria). Two patients in the HAI group and five patients in the control group were dead of disease at the time of last follow-up. The 1-year, 3-year, and 5-year cumulative survival rates for the HAI group were 88.9%, 77.8%, and 77.8%, respectively, whereas those of the control group were 100.0%, 50.0%, and 50.0%, respectively (P = 0.2686).

CONCLUSIONS

This randomized study revealed that short term HAI of 5-FU after curative resection of colorectal hepatic metastases is effective in preventing the recurrence of disease without any serious complications.

Measurement of hepatocyte growth factor in serum and plasma

To investigate whether serum or plasma should be used for the measurement of blood hepatocyte growth factor, the levels were compared in 28 normal subjects and 30 patients who had undergone surgery. The serum level was significantly higher than the plasma level. The serum and plasma hepatocyte growth factor levels differed markedly depending on the subjects, although overall there was a significant correlation between levels (r=0.862, P=0.0001). In serum obtained by the clotting of platelet- or leukocyte-containing plasma with thrombin, hepatocyte growth factor increased in proportion to the number of leukocytes. The difference between serum and plasma hepatocyte growth factor levels also correlated with the number of leukocytes in the patients (r=0.642, P=0.0004). Such a correlation was not observed for platelets. These findings suggest that the serum hepatocyte growth factor level does not strictly reflect the in vivo blood level, due to the release from leukocytes during sample preparation (i.e., blood clotting ) and that plasma is more suitable for assay of blood hepatocyte growth factor.

Evaluation of preoperative and intraoperative arterial stimulation and venous sampling for diagnosis and surgical resection of insulinoma

BACKGROUND

The precise intraoperative localization of insulinoma is essential for successful surgical treatment. In addition to various imaging modalities developed recently, arterial stimulation and venous sampling (ASVS) has also been used for tumor localization.

METHODS

Preoperative and intraoperative ASVS procedures were performed in 6 patients with insulinoma. Intraoperative ASVS was performed before and after tumor resection. Immunoreactive insulin (IRI) concentrations and the IRI ratio (IRI concentration at each time interval after calcium injection/baseline IRI concentration) were determined by the conventional or a quick IRI method.

RESULTS

The site of the tumor was identified preoperatively in all patients. The peak of the IRI ratio varied widely, but setting the cutoff value at 3.0 clearly differentiated peak IRA ratios in feeding arteries from those of nonfeeding arteries. Intraoperative ASVS showed a similar elevation of IRI levels, but the elevation disappeared after tumor resection in all but 1 patient. In 2 patients, resection of the tumor was confirmed during surgery by measuring IRI levels by the quick IRI method.

CONCLUSIONS

A combination of ASVS and conventional imaging modalities is useful for precise localization of insulinoma. Resection of the tumor can be confirmed intraoperatively by comparing IRI levels associated with preoperative and postresective ASVS.

[The efficacy and limitation of hepatic arterial infusion chemotherapy for colorectal liver metastases]

We investigated the efficacy and limitation of hepatic arterial infusion (HAI) chemotherapy for colorectal liver metastases. In terms of prophylactic HAI following curative resection of liver, the 5-year disease-free survival of HAI group (12 g of 5-FU administered in 6 weeks) was 66.7%, whereas that of randomly selected control group was 20.0%. The difference was statistically significant (p = 0.045). Recurrent disease was confirmed in three cases of HAI group (one in liver) and in 8 patients of the control group (6 in liver). However, the overall survival was not significantly different between the groups. Thus, the short-term HAI of 5-FU is effective in decreasing the recurrence of disease. As for the treatment of unresectable liver metastases, some patients received HAI of 5-FU (1,000-1,500 mg/w) showed prolonged survival with partial remission of the disease. However, the 1-, 2-, and 3-year cumulative survival of HAI group (n = 27) was 69.3, 34.1 and 11.4%, respectively, against 61.3, 22.6 and 9.4%, respectively, in the transarterial embolization (TAE) group (n = 31). Therefore it is important to estimate the effect in the early phase of HAI, and aggressively continue the treatment in selected patients for whom it is suitable.

Pretreatment of crude pancreatic islets with mitomycin C prolongs graft survival time in xenogeneic rat-to-mouse model

BACKGROUND

Rejection of pancreatic islet grafts is still a serious problem. We evaluated the effect of mitomycin C (MMC) on the survival of crude islets grafts after xenogeneic islet transplantation.

METHODS

WS (RT1k) rat islets pretreated with various concentrations of MMC (0, 1, 3.2, 10, 32, 50, 100, 320, and 1,000 microg/ml) were transplanted into C57BL/6 mice with streptozotocin-induced diabetes. In vivo graft function was assessed by a daily measurement of nonfasting blood glucose concentration in each animal. We also examined the separate effect of MMC on purified islets and contaminants present in the crude islet preparation.

RESULTS

MMC at doses of 10, 32, 50, and 100 microg/ml resulted in a significant prolongation of the mean graft survival time from a control of 12.4+/-2.5 days to 23+/-7.4, 17.5+/-5.4, 25.5+/-14.7, and 26.7+/-8.9 days, respectively. Deterioration of glucose metabolism was noted when the dose exceeded 32 microg/ml, whereas at 320 microg/ ml, MMC failed to restore normoglycemia. Prolongation of survival time of crude islets was the result of its effect on islets and contaminant components of the crude islet preparation. In vitro study showed that MMC treatment at a higher concentration than 10 microg/ml reduces the stimulatory as well as proliferative capacity of lymph node cells.

CONCLUSIONS

Pretreatment of pancreatic islets with MMC at 10 microg/ml prolongs xenograft survival without deterioration of in vivo graft function. This novel treatment modality represents a new strategy for the modulation of immunity of islets and contaminants in crude islet preparations.

Microchimerism in thymus is associated with up-regulated T helper type 1 cytokine transcription during cardiac allograft rejection in rats

BACKGROUND

Intrathymic microchimerism (MC) is thought to be responsible for inducing allograft tolerance. However, the role of MC in the thymus gland after transplantation, particularly in the rejection response, is unknown. We investigated serial changes in intrathymic cytokine production associated with MC and allograft rejection.

METHODS

Donor-specific cell injection (DSI) and heterotopic heart transplantation (HTx) were performed in the fully allogeneic combination using DA rats (RT1a) as donors and WS rats (RT1k)as recipients. MC was checked by polymerase chain reaction (PCR) using a donor RT1.Bbeta domain 1 region sequence-specific primers. Reverse transcription (RT)-PCR analysis of cytokine (interleukin [IL]-2, interferon-gamma, IL-4, and IL-10) profiles of the thymus was performed in animals given DSI, HTx, or DSI/HTx.

RESULTS

DSI alone resulted in an immediate development of MC, detected by PCR, in various organs including the thymus, spleen, liver, and blood, of most rats, lasting for over 2 months. However, DSI-induced MC selectively disappeared in the thymus on day 7 after grafting, several days before the rejection of cardiac allograft. RT-PCR analysis of cytokine profiles showed that the levels of Th1 (IL-2 and interferon-gamma) cytokines transcribed in the thymus were higher than in the spleen. MC reappeared in the thymus on day 21 after grafting, but was not associated with elevation of Th1 cytokine transcription when allograft was replaced by fibrosis.

CONCLUSIONS

Intrathymic MC does not always confer unresponsiveness to alloantigen, but can be eliminated after anti-donor response.

Pretreatment of crude pancreatic islets with mitomycin C (MMC) prolongs islet graft survival in a xenogeneic rat-to-mouse model

In this study, we examined the effect of mitomycin C (MMC) treatment on graft survival and evaluated its efficacy in immunomodulation of islet graft for transplantation. Male WS rats were used as islet donors and streptozotocin-induced diabetic C57BL/6 mice as recipients. The isolated islets were treated with MMC at concentrations of 0, 0.1, 1, 3.2, 10, 32, 100, 320, and 1000 microg/mL for 30 min, and were cultured for 20 h. Then, 300-400 islets were transplanted into the renal subcapsular space of diabetic mice. Significant prolongation of graft survival was obtained when the islets were treated with MMC at a concentration of 10, 32, or 100 microg/mL (MST 23 +/- 7.4, 17.5 +/- 5.4, 29.6 +/- 9.7 days: p < 0.003, p < 0.012, p < 0.001, respectively, vs. 12.3 +/- 2.7 days for culturing alone). Islets treated with MMC at a concentration of 320 microg/mL or more failed to restore normoglycemia in the diabetic recipient mice after transplantation. Viability of islets incubated with doses up to 100 microg/mL, assessed under the confocal microscope after propidium iodide and Hoechst 33342 staining, was maintained well comparable to that of freshly isolated islets, while those treated at 320 microg/mL was significantly decreased. Thus, a therapeutic window for MMC efficacy was found at concentrations from 10 microg/mL to 100 microg/mL. This modality is simple and effective and underlying molecular mechanisms need to be determined in the future.

[Intra-arterial chemotherapy to improve quality of life in cases of unresectable advanced or recurrent breast cancer]

We performed repetitive intra-arterial infusion chemotherapy (I.A.) with epirubicin in order to improve the quality of life (QOL) in 3 cases with locally advanced or recurrent breast cancer which were diagnosed as surgically unresectable and seemed uncontrollable by outpatient systemic chemotherapy. The patients were admitted to our hospital for chest wall invasion, lymph node metastasis, bleeding, pain, or edema in upper extremity. Therapeutic effects included 1 case of CR and 2 cases of PR in the primary site, and similar effects were obtained in metastasized lymph nodes. We could perform mastectomy in both of the 2 cases with locally advanced cancer after I.A., Although leukocytopenia, which was the dose limiting factor in this regimen, was observed in all 3 cases, it was Grade 2 or 3 and recovered by G-CSF. With regard to their QOL, symptoms which had driven them to inpatient treatment remarkably improved in all of the cases. Thus, after 2 series of I.A. they could receive maintenance systemic chemotherapy as outpatients. Our findings showed that the I.A. as a local control treatment in patients with unresectable advanced or recurrent breast cancer is useful for the improvement of their QOL.

[Long-term survival in a case of multiple liver metastasis from postoperative gastric cancer effectively treated by hepatic intraarterial infusion chemotherapy using MMC and pirarubicin]

We experienced a case of multiple liver metastasis from postoperative gastric cancer who showed long-term survival with hepatic arterial infusion chemotherapy (HAI) of MMC and pirarubicin. A catheter was inserted into the hepatic artery, and 4 mg of MMC and 20 mg of pirarubicin were administered through an implantable port catheter every two to four weeks. The total dose of MMC and pirarubicin by the time of this report was 164 mg and 820 mg, respectively. The follow-up CT scan 2 months after the beginning of HAI showed a decrement of the liver tumors. The decrease rate at 12 and 17 months was 50% and 70%, respectively, which was diagnosed as partial response (PR). The therapeutic effect at 49 months is still PR without any sign of tumor enlargement of extra hepatic lesion.

Detection of K-ras gene mutations in plasma DNA of patients with pancreatic adenocarcinoma: correlation with clinicopathological features

We investigated the presence of K-ras gene mutation in plasma DNA and assessed its clinical value in patients with pancreatic adenocarcinoma. Mutations in codon 12 of the K-ras gene were examined by mutant allele-specific amplification method using DNA extracted from surgical specimens and plasma samples of 21 patients with pancreatic adenocarcinoma. K-ras gene mutation was detected in 15 of 21 (71%) primary tumors. In 9 of 15 (60%) patients with K-ras gene mutation-positive tumors, an identical mutation was detected in the plasma DNA. None of four patients with chronic pancreatitis or five healthy subjects had such mutations in plasma DNA. Tumors positive for K-ras gene mutation in plasma DNA were significantly larger (P = 0.04) and less likely to result in a curative cure after surgical resection (P = 0.09) than those negative for the mutation. Other clinicopathological features, including age, sex, histological type, mode of invasion, and metastasis, did not correlate with K-ras gene mutations in plasma DNA. Treatment resulted in disappearance of K-ras gene mutations in plasma DNA in six of nine (67%) patients. Three patients with a persistently positive K-ras gene mutation in pre- and post-treatment plasma samples were likely to show early recurrence or have a progressive disease. Our findings suggest that K-ras gene mutation can be detected in plasma DNA of patients with pancreatic adenocarcinoma. Detection of K-ras mutations in plasma may be clinically useful for evaluating tumor burden and efficacy of treatment.

Direct antigen presentation through binding of donor intercellular adhesion molecule-1 to recipient lymphocyte function-associated antigen-1 molecules in xenograft rejection

Cellular interactions that lead to graft rejection were examined in a rat-to-mouse xenogeneic combination using species-specific monoclonal antibodies (mAbs) against donor and recipient intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) molecules, respectively. Although both mAbs displayed moderate blocking activity in an in vitro mixed lymphocyte response assay, strong suppression was observed when anti-donor (rat) ICAM-1 mAb was combined with anti-recipient (mouse) LFA-1 mAb. Likewise, significant prolongation of islet xenograft survival was observed with these mAbs. Thus, 0.05 mg of anti-mouse LFA-1 mAb and anti-rat ICAM-1 mAb given on days 0 and 1 produced significant prolongation of graft survival over the control (51+/-20 days vs. 10+/-3 days, P<0.0001), but not when anti-mouse ICAM-1 mAb was combined with anti-mouse LFA-1 mAb (13+/-3 days). In this species combination, mouse T cells were able to proliferate in the presence of rat antigen-presenting cells (APCs) in a cell number-dependent manner, but not in the presence of mouse APCs. The binding assay showed that LFA-1 molecules on mouse T cells can bind immobilized rat ICAM-1 molecules. These results suggest that rat ICAM-1 molecules on APCs can interact with mouse LFA-1 molecules on T cells across a species barrier and that this binding generates the consequent immune responses leading to rejection. mAb treatment against these adhesion molecules of recipient as well as donor is crucial for preventing rejection in a xenogeneic transplantation model.

Protection of islet allografts transplanted together with Fas ligand expressing testicular allografts

Fas ligand (FasL) is highly expressed in testicular tissues and thought to be responsible for protection from allograft rejection by inducing apoptosis of anti-graft activated T cells. FasL-expressing islets have been shown to induce a granulocyte-mediated inflammatory reaction. We investigated whether a graft can be protected from alloimmune responses by manipulating the Fas/FasL-system. We transplanted allogeneic islets under the kidney capsule of streptozotocin-induced diabetic mice together with testicular tissue. Significant prolongation of survival of C3H islet allograft was observed in C57BL/6 (B6) recipients transplanted with C3H testicular tissue, but not in those transplanted with C3H-gld testicular tissue expressing non-functional FasL. No significant prolongation was observed in B6-lpr recipients expressing non-functional Fas. Immunohistochemical staining of C3H testicular tissue in the composite graft showed a high expression of FasL, but not that of the C3H-gld testicular tissue. In situ terminal deoxynucleotidyl transferase-mediated dUDP-biotin catalysed DNA nick-end labelling (TUNEL) staining of a composite graft of C3H islet and testicular tissue in B6 recipients demonstrated extensive apoptosis of infiltrating mononuclear cells around the graft. The protective effect of C3H testicular tissue was abrogated when anti-FasL monoclonal antibody was administered i.p. postoperatively. Our results suggest that FasL-positive testicular allografts protect composite islet allografts and indicate that manipulation of Fas/FasL mediated apoptosis is a suitable strategy for controlling rejection of islet allografts.

Awareness of donor alloantigens in antiadhesion therapy induces antigen-specific unresponsiveness to islet allografts

BACKGROUND

Antiadhesion therapy using monoclonal antibodies (mAbs) to adhesion molecules in vivo has been shown to produce significant prolongation of graft survival in various transplantation models. However, it remains unclear whether antiadhesion therapy operates by merely blocking adhesion between antigen-presenting cells and T cells physically and/or by blocking costimulatory signals while preserving signals mediated through T-cell receptors in vivo. We examined antigen-specific T-cell responses during and after antiadhesion therapy.

METHODS

BALB/c islets were transplanted into the renal subcapsular space of streptozotocin-induced diabetic C57BL/6 mice given anti-lymphocyte function-associated antigen (LFA)-1 and/or anti-intercellular adhesion molecule-1 mAb treatment. The animals bearing surviving islet allografts were challenged with BALB/c or third-party islets on day 7 or more than 100 days after transplantation.

RESULTS

Islet allografts were acutely rejected in untreated animals, with a mean survival time (MST) of 19+/-8 days. Administration of anti-LFA-1 mAb induced significant prolongation of graft survival with a mean survival time of 72+/-33 days, and half of the allografts showed indefinite survival. The animals given anti-LFA-1 mAb alone 7 days before transplantation showed acute rejection of BALB/c islets, whereas a significant number of animals given anti-LFA-1 mAb and the BALB/c islet allograft simultaneously accepted secondary BALB/c islets, but rejected third-party islets. Likewise, most of the animals bearing long-term functioning BALB/c allografts for more than 100 days accepted secondary BALB/c islets, but rejected C3H islets acutely. Interestingly, the spleen cells from these animals transferred unresponsiveness to BALB/c islets into the 2.5-Gy x-irradiated recipients, whereas those from naive animals induced acute rejection.

CONCLUSIONS

These results indicate that anti-LFA-1 mAb treatment prevents T-cell activation leading to rejection, but results in a T-cell receptor engagement leading to antigen-specific unresponsiveness maintained by transferrable suppressor cells.

[The change of hepatic energy status after transcatheter arterial embolization (TAE) for hepatocellular carcinoma--a study using 31P-MRS]

In six patients with hepatocellular carcinoma, adenosine triphosphate (ATP) phosphomonoester (PME), phosphoric acid (Pi) and pH were measured before and after transcatheter arterial embolization (TAE), using 31P-magnetic resonance spectroscopy (MRS). The effectiveness of TAE was judged by the extent of lipiodol accumulation within the tumor and change in serum alphafetoprotein level. The pH within the tumor decreased 2-9 days after TAE in all the cases, and beta ATP/Pi ratio decreased when TAE was effective, whereas the ratio did not decrease when TAE was ineffective. The beta ATP/Pi ratio measured by 31P-MRS seems to be a useful, non-invasive marker of the anti-tumor effect of TAE, although further investigation is needed.

[Transarterial immuno-embolization therapy in patients with hepatocellular carcinoma]

Surgical resection, transcatheter arterial embolization (TAE) and percutaneous ethanol injection therapy (PEIT) are effective for hepatocellular carcinoma (HCC), but the recurrence rate is high. We have devised a new therapy of transarterial immuno-embolization (TIE) with OK-432, fibrinogen and thrombin, and 2 cases are reported. Case 1: A 78-year-old Japanese male with HCC (diameter, 4 cm in subsegment 5) received TIE. The tumor size was markedly decreased, and the patient survived for more than 3 years without recurrence. Case 2: A 61-year-old Japanese male with HCC (diameter, 4.5 cm in segment 5) received hepatic subsegmentectomy following TIE. Histological examination of resected specimens following TIE showed massive infiltration of mononuclear cells in the main tumor. Tumor recurrence had developed three times thereafter, but was effectively treated by TIE. TIE may be an effective therapy for HCC.

Prolongation of cardiac allograft survival by intraportal injection of donor antigens--differential mechanisms according to the timing of injection

Recently, we reported that intraportal (IP) injection of donor spleen cells (SPCs) before transplantation as well as at the time of transplantation significantly prolongs cardiac allograft survival in rats (7). Long-term establishment of chimerism induced by intraportal administration of SPCs could be a part of this prolongation. In this study, we examined the effect of irradiation of SPCs as a source of donor antigens on cardiac allograft survival. Experiments were carried out using DA (RT1a) as the donor and BUF (RT1b) as the recipient strain. Fifty million irradiated or nonirradiated SPCs were injected either intravenously (i.v.) or intraportally (i.p.) on day -10 or day 0, the day of cardiac allografting. Untreated animals rejected allografts within a mean survival time (MST) of 7.2 +/- 0.8 days (n = 5). Injection (i.p.) of SPCs on both day -10 (n = 4) and day 0 (n = 6) induced significant prolongation of MST over the control (19.0 +/- 4.7, 14.2 +/- 2.1 days; p < 0.001 vs. control), while i.v. injection of SPCs on either day -10 (n = 4) or day 0 (n = 4) failed to do so (9.2 +/- 1.0, 8.5 +/- 0.6 days). Significant prolongation was still observed when irradiated SPCs were injected on day -10 (n = 4; MST: 19.0 +/- 5.4 days, p < 0.002 vs. control), but not when injected on day 0 (n = 5; MST: 9.4 +/- 2.1 days). These data suggest that the immunosuppressive effect of i.p. injection of donor SPCs could be induced by differential mechanisms according to the timing of inoculation of donor antigens.

Analysis of donor reactive cells in ALS-treated mice bearing skin allografts after the intrathymic injection of donor specific spleen cells

The intrathymic injection of donor spleen cells into antilymphocyte serum (ALS)-treated mice induces significant prolongation of donor skin grafts. The intrathymic route of antigen presentation in this model is superior to the intravenous route in achieving unresponsiveness. To elucidate possible mechanisms involved in the induction of unresponsiveness in ALS-treated mice after intrathymic injection of donor spleen cells, we have analysed the reactivity of lymphoid cells from unresponsive mice in various ways. Deletion of donor reactive cells has been studied using the Mls antigen system. Functional inactivation was analysed by a sequential study of the frequency of donor reactive cells. Suppressor cell activity was studied using an adoptive transfer assay. Deletion of donor reactive cells was partial and occurred largely in the spleen in both early and late stages of unresponsiveness. The frequency of donor reactive cytotoxic cells was suppressed in both spleen and lymph nodes from day +/- 13 until grafts were rejected, with the exception of a rebound period at day +/- 22. In contrast, donor reactive cells were not deleted or inactivated in the thymus. Suppressor cell activity could only be detected in mice bearing long-term grafts. These results suggest that donor reactive cytotoxic cells are functionally inactivated in the spleen and nodes in the early and late stages of unresponsiveness after intrathymic injection of antigen. In contrast, donor reactive cells in the thymus do not appear to be affected.

Systemic production of interleukin-6 following acute inflammation

The present study was designed to evaluate whether IL-6 is produced locally or systemically following acute inflammation. Full-thickness scale burns were made on rats. Serum IL-6 levels (SIL-6) showed a constant time-dependent change with a single peak 6 hours after the burn. SIL-6 elevation was correlated with the ratio of burn area to total body surface area. The liver, spleen, lymph node and skin harvested after the burn secreted significantly higher amounts of IL-6 after tissue culture when compared with those taken from sham rats. The venous serum drainage from the burn site induced significantly higher IL-6 production of splenocytes than the arterial and control venous sera. In conclusion, IL-6 production is rapidly and systemically triggered by a humoral factor following acute inflammation in vivo, resulting in constant kinetics for SIL-6.

Minimum number of islets required to maintain euglycemia and their reduced immunogenicity after transplantation into diabetic mice

In streptozocin (SZ)-induced diabetic mice, 200 islets, but not 50 islets, consistently restore euglycemia within 1 week of transplantation. To determine the minimum number of islets sufficient to maintain euglycemia in a diabetic mouse, we first transplanted 50 and 150 syngeneic islets simultaneously into the right (RK) and left kidney (LK), respectively, and then removed the LK 1 week post-transplantation. The remaining 50 islets maintained euglycemia in 8 of 11 mice with normal intravenous glucose tolerance tests (IVGTT). Protection of 50 islets for at least 7 days was necessary because removal of the 150 islets at 5 or 3 days resulted in a much lower incidence of persistent euglycemia. Similarly, 25 islets were capable of maintaining euglycemia in 2 of 9 mice once hyperglycemia was reversed by split-transplantation of 25 (RK) and 175 (LK) islets. To examine if 50-islet allografts survive longer than 200-islet allografts, we split-transplanted 50 DBA/2 islets in the RK and 150 islets of either B6 (syngeneic), DBA/2 (allogeneic), or C3H/He (third party allogeneic) mouse origin in the LK in 3 groups of diabetic C57BL/6 (B6) mice. The survival of 50 DBA/2 islets in each group after removal of the LK on day 7 was compared to that of 200 DBA/2 islets in control B6 mice. Maximum prolongation of allograft survival was obtained with 50 DBA/2 islets that were split-transplanted with syngeneic B6 islets. These results clearly demonstrate that 50 islets are sufficient to maintain normal glucose tolerance once euglycemia is induced by transplantation of a larger number (i.e., 200) of islets and that 50 islet allografts are much less immunogenic than 200-islet allografts.

Treatment of severe diabetes mellitus for more than one year using a vascularized hybrid artificial pancreas

We report the successful application of a hybrid artificial pancreas device for the treatment of severe diabetes mellitus induced by total pancreatectomy in two dogs. Control of the blood sugar was achieved for more than 1 year in these two animals without any immunosuppressive therapy. Although exogenous insulin was required therapy. Although exogenous insulin was required during the latter part of the study period, removal of the devices resulted in a rapid increase in the fasting blood sugar levels and the exogenous insulin requirements (P < 0.001 versus weeks 1-52 in both dogs). Metabolic studies, postexplant in vitro studies, and histologic analyses confirmed islet cell survival and insulin production by the devices. This hybrid artificial pancreas has a clear clinical potential for islet cell transplantation without immunosuppression.

Serum interleukin-6 levels as an indicator of acute rejection after liver transplantation in cynomologous monkeys

This study was designed to evaluate whether the sequential monitoring of serum interleukin-6 levels (SIL-6) could be helpful for diagnosing the occurrence of hepatic allograft rejection. An SIL-6 post-transplant study was conducted on nine cynomolgus monkeys which had undergone orthotopic hepatic allotransplantation, six of which were treated with FK-506 (a new immunosuppressant agent isolated from Streptomyces tsukubaensis) and three of which were not. All the nontreated animals showed biochemical abnormalities from days 5-6, characterized by a marked elevation of serum alkaline phosphatase levels, and they eventually died on days 8, 12, and 63 (group I). Acute cellular rejection was confirmed by histological study of the hepatic grafts taken at autopsy or biopsy. On the other hand, four of the treated animals (group IIa) survived more than 30 days. Biochemical examination of this group showed no abnormal signs apart from a slight elevation of alkaline phosphatase (< 2000 IU/l). Histological examination carried out around 30 days after transplantation revealed a transient infiltration of polynuclear cells into Glisson's area, with the portal vein and bile duct remaining intact. The remaining two animals (group IIb) died of dehydration and arterial thrombosis on days 5 and 7, respectively. A kinetic study of SIL-6 conducted during the first 2 weeks showed quite different patterns among the three groups. All recipients in group I demonstrated two peaks following grafting on days 1 and 3 or 4, the second peak of above 2.0 U/ml preceding biochemical abnormalities by 2 to 3 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of specific unresponsiveness (tolerance) to skin allografts by intrathymic donor-specific splenocyte injection in antilymphocyte serum-treated mice

Although chronic immunosuppression has been extremely successful in clinical organ transplantation, it is associated with severe complications such as opportunistic infections, spontaneous neoplasms, drug toxicities, metabolic complications, and the inability to control rejection. We therefore have investigated the ability of allogeneic donor lymphoid cells to produce specific tolerance following intrathymic (IT) injection into allograft recipients. Groups of B6AF1 mice received ALS on days -1 and +2 relative to C3H/He skin grafts on day 0; experimental groups received 1, 5, or 10 x 10(7) syngeneic (B6AF1) or allogeneic (C3H) spleen cells (SPCs) by IT injection on day +7. IT injection of C3H splenocytes significantly prolonged allograft survival at all cell doses tested when compared with ALS controls. The best survival was obtained following IT injection of 5 x 10(7) C3H cells (median survival time [MST] = 132 days; ALS controls = 21.5 days), with 8 of 13 skin grafts surviving longer than 100 days. IT injection of syngeneic splenocytes or third-party DBA/2 splenocytes did not prolong allograft survival beyond that observed in ALS controls. C3H spleen cells injected IT into ALS treated mice on day 0 relative to grafting of C3H skin also produced significant allograft survival (1, 5, or 10 x 10(7) SPCs = MSTs of 75, 47, and 35, respectively) but the results were inferior to those obtained by 5 x 10(7) SPCs IT on day +7. Spleen cells (1 or 5 x 10(7)) injected intraperitoneally or intravenously prolonged allograft survival beyond that seen in ALS controls but were inferior to IT injection at all doses and times studied. Bone marrow, thymocytes, or lymph node cells (5 x 10(7) cells) were substituted for SPCs for IT injection. IT injection of BM, LN or thymocytes all significantly prolonged graft survival over ALS controls. However none of these cell types was as effective as IT splenocytes. Eight B6Af1 recipients of IT splenocytes bearing C3H skin grafts for > 100 days received a second C3H skin graft as well as a simultaneous third-party B10.AKM skin graft. All rejected third-party grafts in normal first-set fashion. Three tolerated both 1st and 2nd C3H grafts without any sign of rejection; 1 rejected the 2nd C3H graft while tolerating the 1st graft; and 4 rejected the 2nd C3H graft in an attenuated fashion but also rejected the 1st graft at the same pace.(ABSTRACT TRUNCATED AT 400 WORDS)

Biliary interleukin 6 levels as indicators of hepatic allograft rejection in rats

Interleukin 6 has recently been noted to be present during the rejection response to grafted organs. In this study, we investigated biliary and serum interleukin 6 levels following liver transplantation in rats. IL-6 levels in bile and serum of naive rats were below 0.6 U/ml and 0.5 +/- 0.2 U/ml (mean +/- SD), respectively. Both biliary and serum IL-6 levels showed high values (greater than 10.0 U/ml and greater than 1.6 U/ml, respectively) on the day after transplantation, which seemed to reflect the inflammatory status caused by the surgical stress. Later samplings showed that the kinetics of serum IL-6 differed among the animals without any definite feature related to graft rejection. In contrast, biliary IL-6 levels correlated well with the severity of the rejection response as determined histologically. Biliary IL-6 levels started to rise at the onset of the rejection response (6.6 +/- 0.6 U/ml), increased further with its progression (19.3 +/- 7.8 U/ml), and then finally fell in the terminal stage (less than 2.0 U/ml). Elevation of biliary IL-6 was observed at an early stage when abnormalities could be detected histologically but not in liver function tests and bile flow. Therefore, biliary IL-6 levels may be of value for the early diagnosis of rejection following liver transplantation.

Interleukin-6 as a new indicator of inflammatory status: detection of serum levels of interleukin-6 and C-reactive protein after surgery

Postoperative serum interleukin-6 (SIL-6) and C-reactive protein (SCRP) levels were examined in 71 patients who underwent various types of abdominal surgery. Similar time-dependent changes in SIL-6 and SCRP levels were observed in 12 patients despite differences in surgical procedures and liver function among the patients. SIL-6 started to increase within 3 hours after the beginning of the operation and reached a peak after 24 hours. SCRP started to increase after 12 hours and was maximum at 48 to 72 hours. The increase in SIL-6 at 24 hours (delta IL-6) showed a close correlation with that of SCRP at 48 hours (delta CRP) in 53 patients without liver cirrhosis. In 18 patients with liver cirrhosis, delta CRP relative to delta IL-6 was less than that in patients without cirrhosis and was poorly correlated with the latter. delta IL-6 was correlated with the length of time of the operation and blood loss in both groups, but delta CRP showed no significant correlation with these factors in either group. These findings indicate that the increase in IL-6 triggered by a surgical procedure may function as a hepatocyte-stimulating factor and that monitoring of SIL-6 may be more helpful than monitoring of SCRP for estimation of inflammatory status and early detection of an acute-phase response.

Improvement in islet yield from a cold-preserved pancreas by pancreatic ductal collagenase distention at the time of harvesting

This study tried to improve the number of viable islets isolated from a pancreas because a sufficient number cannot be obtained when the organ is preserved in the manner used for pancreas transplantation. The mechanism involved in the decrease in islet yield during preservation was studied to try to develop a better method for islet preparation. First, the integrity of the ductal system was compared between fresh and 6-hr simply preserved (in Hanks' balanced salt solution) rat pancreases. The ductal pressure after ductal injection of HBSS reached a plateau earlier and was significantly lower for the preserved pancreases (0.073 +/- 0.026 min, 410 +/- 17 mmHg, n = 5) than for the fresh ones (0.176 +/- 0.086 min, 561 +/- 103 mmHg, n = 7, P less than 0.05). Second, the extent of pancreatic distention was examined following ductal injection of barium gelatin solution. Solution leakage occurred earlier and distention was less in the preserved pancreas. In addition, the gelatin was found in the capillaries within some islets of the preserved pancreas. These results indicated that the preservation led to a rapid loss of integrity of the ductal system before collagenase injection. We therefore tested the efficacy of ductal collagenase injection at the time of harvesting: 15 ml of 1.0 mg/ml collagenase HBSS was intraductally injected and the pancreas was preserved at 4 degrees C for 2, 4, 6, and 24 hr. The isolation procedure was similar to that used for the fresh pancreas. The yield was significantly better than that of the simply preserved pancreas at 4 hr (241 +/- 22, n = 3, vs. 140 +/- 58, n = 3, P less than 0.05) and at 6 hr (171 +/- 58, n = 14, vs. 32 +/- 33, n = 6, P less than 0.01). These isolated islets were spherical-oval and their viability was confirmed by the ability to reverse STZ-induced diabetes in mice. These results indicated that the integrity of the ductal system, which is necessary for distention of the whole pancreas, was lost during preservation. To solve this problem, ductal collagenase injection should be done at the time of pancreas harvesting and then followed by simple preservation. This method is recommended to obtain viable islets from a preserved pancreas.

[Two cases of cloacogenic carcinoma of the anal canal: chemotherapeutic effect of cis-dichlorodiammine-platinum]

Cloacogenic carcinoma, originating from the remnant of the cloaca, is a rare malignant tumor, comprising 2-3% of cancers of the anal canal. We reported here two cases of cloacogenic carcinoma whose pulmonary and hepatic metastases were successfully treated with CDDP administration, in spite of limited effect on primary lesions of the rectum. The promising usage of CDDP for cloacogenic carcinoma, especially for distant metastasis was discussed.