Totally laparoscopic resection of right-sided colon cancer using transvaginal specimen extraction with a 10-mm-long abdominal incision.

BACKGROUND: Natural orifice specimen extraction (NOSE) has been developed as a means of decreasing the incidence of surgical wound complications. We refined the procedure for totally laparoscopic colectomy with transvaginal specimen extraction using the reduced port surgery technique with the ultimate goal of attenuating damage to the abdominal wall. We herein report this innovative technique and its short- and long-term outcomes. METHODS: We prospectively collected data on seven patients who underwent totally laparoscopic colectomy using transvaginal specimen extraction with a 10-mm-long abdominal incision for right-sided colon cancer from January 2014 to December 2021. Two 5-mm ports were used in the procedure without laparotomy. Transverse transabdominal posterior colpotomy was then performed. We introduced a GelPOINT Mini advanced access platform (Applied Medical, Rancho Santa Margarita, CA, USA) into the transvaginal route for the insertion of a laparoscope, forceps, and stapling device. Lymph node dissection and transection of the ileum and distal colon were performed with transvaginal assistance. A specimen was then extracted transvaginally. Intracorporeal functional end-to-end anastomosis was conducted using a linear stapler through the vagina. After the removal of GelPOINT Mini, the vaginal incision was closed transvaginally. RESULTS: Seven patients successfully underwent this procedure. Median operative time was 219 min (range 174-255 min), median blood loss was 23 ml (range 10-37 ml), median number of harvested lymph nodes was 21 (range 17-35 lymph nodes) and median margins were 17.0 cm (range 9.0-25.0 cm) for the proximal margin and 9.5 cm (range 5.0-13.0 cm) for the distal margin. There were no complications more severe than Clavien-Dindo Grade II and there was no mortality. The median frequency of use intravenous analgesics from postoperative day 1 to discharge was once. Two patients did not require analgesics. A node-positive patient developed recurrence at the lung and paraaortic lymph nodes. CONCLUSIONS: This procedure appears to be feasible, safe, and oncologically acceptable for selected cases.

Generation of dendritic cells from leukaemia cells of a patient with acute promyelocytic leukaemia by culture with GM-CSF, IL-4 and TNF-alpha.

Dendritic cells are potent antigen-presenting cells derived from CD34+ haemopoietic stem cells. Dendritic cells have been reported to be generated from cells in granulocytic lineage as well as monocytes, blood dendritic cell precursors and lymphoid progenitors. In order to explore the differentiation pathway of dendritic cells from granulocytic cells and the applicability of leukaemia-derived dendritic cells for anti-leukaemic immunotherapy in acute leukaemia of granulocytic origin, we tried to generate dendritic cells from leukaemia cells of a patient with acute promyelocytic leukaemia (APL). Leukaemia cells were cultured with GM-CSF, IL-4 and TNF-alpha for 10 days. Azurophilic granule-containing cells with marked cytoplasmic projections were generated in the culture. FACS analysis of these cultured cells revealed the generation of CD1a+, CD83+, CD80+, CD86+, CD40+ and HLA-DR+ cells. The leukaemic origin of these dendritic-like cells was demonstrated by in situ hybridization of magnetic-bead-sorted CD1a+ dendritic cells using the DNA probes of t(15;17). Cells generated by culturing leukaemia cells were demonstrated to have a potent antigen-presenting function in allogeneic mixed leucocyte cultures. These findings show the plausibility of the previously reported pathway of dendritic cell maturation through granulocytic cells and suggest the possibility of anti-leukaemic immunotherapy using leukaemia-derived dendritic cells even in patients with acute promyelocytic leukaemia.

[Three cases of malignant lymphoma accompanied by renal cell carcinoma].

Three cases of malignant lymphoma (ML) accompanied by renal cell carcinoma (RCC) are reported. From September 1997 through August 2000, we treated 85 patients with ML. Among these patients, three had accompanying RCC (clear cell type): case 1, a 57-yr-old man with gamma/delta-T cell lymphoma; case 2, a 25-yr-old man with Grade 3 follicular lymphoma; case 3, a 64-yr-old man with MALToma of the right orbit. Renal cell carcinoma is a relatively rare disease, but several reports have indicated that, for some reason, the incidence of concurrent RCC and ML is higher than expected. It is possible that the two malignancies share some common background factors, such as genetic mutation, immunological abnormality, or an immunomodulatory effect of the first tumor. The patient in case 2 was thought to have an abnormal immunological background from his medical history, which included bronchial asthma, idiopathic thrombocytopenic purpura, and mesangial proliferative glomerulonephritis (non-IgA type). Therefore the combination of ML and RCC in this patient may have been due to immunological impairment.

Extramedullary T lymphoid blast crisis representing an additional translocation, t(6;8)(q25;q22) in a patient with Philadelphia-positive chronic myelogenous leukemia after allogeneic bone marrow transplantation.

A patient with extramedullary crisis from chronic myelogenous leukemia after allogeneic bone marrow transplantation is reported. A pathological neck lymph node observed after transplantation revealed pre-T lymphoblastic phenotype, and the fluorescence in situ hybridization (FISH) analysis showed recipient type sex chromosomes and bcr/abl fusion gene. The cells represented an additional translocation, t(6;8)(q25;q22). No rearrangements of the T-cell receptor (TCR) beta, gamma or delta chain genes were observed. The absence of TCR rearrangement indicated the clonogenic involvement of pluripotent hematopoietic stem cells by Philadelphia chromosome. Bone marrow specimens at that time showed donor type sex chromosomes and no bcr/abl-positive cells by FISH.

Leukemia blast-induced T-cell anergy demonstrated by leukemia-derived dendritic cells in acute myelogenous leukemia.

OBJECTIVE: To elucidate the mechanism of immunologic escape of leukemia cells and establish an effective anti-leukemia immunotherapy, we attempted to generate dendritic cells from leukemia cells in patients with acute myelogenous leukemia (AML). Using these leukemia-derived dendritic cells, we investigated leukemia cell-associated T-cell anergy. MATERIALS AND METHODS: Leukemia cells of 30 patients with AML were cultured with granulocyte-macrophage colony-stimulating factor, interleukin-4, and tumor necrosis factor-alpha. Cultured leukemia cells were evaluated for antigen-presenting ability by mixed leukocyte culture (MLC). Normal lymphocytes, which were cocultured with leukemia blasts in the first MLC, were cultured with leukemia-derived dendritic cells in the second MLC. RESULTS: In cultures of leukemia cells from 21 of 30 patients examined, cells with stellate morphology and cell fractions with CD1a(+) and/or CD83(+) were present. Autologous MLC using lymphocytes obtained in remission phase as responders as well as allogeneic MLC demonstrated antigen-presenting ability in leukemia-derived dendritic cells. Leukemia cells of FAB-M0, M1, M2, M3, or M6 morphology/phenotype gave rise to dendritic cells as well as leukemia cells of M5. The leukemic origin of dendritic cells was suggested by in situ hybridization. By coculture with CD80(-) leukemia blasts, the response of normal lymphocytes to leukemia-derived dendritic cells cultured from the same individual as that of leukemia blasts was markedly reduced, compared with the lymphocytes cultured with leukemia blasts from a different individual as leukemia blasts. CONCLUSIONS: Escape of leukemia cells from anti-leukemia immunity may be associated with T-cell anergy caused by leukemia blasts. The results of the present study suggest that leukemia-derived dendritic cells can be applied efficiently in anti-leukemia immunotherapy.

Gene correction in hematopoietic progenitor cells by homologous recombination.

Homologous recombination (gene targeting) has many desirable features for gene therapy, because it can precisely correct mutant genes and restore their normal expression, and random nonhomologous integration of DNA is infrequent in cells in which homologous recombination has occurred. There are, however, no reports of attempts to use homologous recombination to correct mutant genes in normal hematopoietic stem cells (HSCs), which are prime cells for therapy of a variety of hematological and other conditions, presumably because of their low abundance and uncertainty that homologous recombination can occur at a usable frequency in these cells. The experiments reported here encourage optimism in this respect by demonstrating targeted correction of a defective hypoxanthine phosphoribosyltransferase gene in hematopoietic progenitor cells that can form colonies in methylcellulose culture. These clonogenic cells are in the same lineage as HSCs but are more abundant and more mature and so less pluripotent. Corrected colonies were identified by their survival in selective medium after electroporation of correcting DNA into unfractionated mouse bone marrow cells and were confirmed by reverse transcription-PCR and sequencing. The observed frequency (4.4 +/- 3.3 x 10(-5) per treated clonogenic cell) is the same as in embryonic stem cells (2.3 +/- 0.4 x 10(-5)) with the same DNA and mutation. These data suggest that gene targeting to correct mutant genes eventually will prove feasible in HSCs capable of long-term bone marrow reconstitution.

[A case report of esophageal small cell carcinoma responding well to chemotherapy of 5-FU and cisplatin combined with radiotherapy].

A seventy-eight year-old man with esophageal small cell carcinoma was reported. He was treated with chemotherapy of 5-FU and Cisplatin combined with radiotherapy. After 3 Courses of chemotherapy, the tumor almost disappeared. A biopsy specimen revealed moderate dysplasia but did not show residue of small cell carcinoma. The patient had lived with no evidence of cancer recurrence for 1.5 years. He died of lung metastasis and pleuritis carcinomatosa about two years after the first treatment with chemotherapy. Chemotherapy of 5-FU and Cisplatin (combined with radiotherapy) is one of the useful treatments for patients with small cell carcinoma of the esophagus.

Regulation of the expression of MHC class I and II by class II transactivator (CIITA) in hematopoietic cells.

In order to develop an effective immunotherapy for hematological malignancies, we investigated the applicability of class II transactivator (CIITA), which had been demonstrated to regulate the expression of MHC class II (MHC-II) by assembling the transcription factors of MHC-II molecules, for immunotherapy by potentiating the antigenicity of tumour cells by inducing MHC expression. First, 32 hematopoietic cell lines were analysed for the expression of HLA-DR, CIITA, RFX5 or HLA-ABC. Fourteen cell lines were positive and 18 were negative for HLA-DR. All the 14 HLA-DR positive cell lines were demonstrated to express CIITA mRNA by RT-PCR. On the other hand, in all the 18 HLA-DR negative cell lines, the expression of CIITA was not demonstrated. RFX5, which is one of the transcription factors of MHC-II, was expressed ubiquitously in all 32 cell lines. Three cell lines out of 23 hematopoietic cell lines examined were negative for HLA-ABC, and all three of these cell lines were negative for both HLA-DR and CIITA expression. Furthermore, CIITA cDNA was transfected into K562 cells, which were negative for HLA-ABC, -DR and -DQ, but positive for HLA-DP. The transfection rendered HLA-DR negative to positive and increased the expression level of HLA-DP, but HLA-DQ remained negative. In addition to HLA-DR, HLA-ABC was also induced to express by the transfection of CIITA gene. The present study demonstrated that the expression of HLA-DR in hematopoietic cells is regulated in subordination to CIITA and the expression of HLA-DR (and HLA-ABC in K562) is induced by transfection with the CIITA gene. These findings revealed the applicability of CIITA in potentiating anti-tumour immunity of HLA-DR negative tumour cells for immunotherapy of hematological malignancies.

Expression patterns of costimulatory molecules on cells derived from human hematological malignancies.

In order to elucidate the possibility of costimulatory molecules-mediated immuno or immuno-gene therapy for human hematological malignancies, we analyzed 30 hematopoietic cell lines and cells obtained from 48 patients with hematological malignancies for the expression of costimulatory molecules such as CD80 and CD86. The 30 hematopoietic cell lines were composed of 4 cell lines derived from the patients with T-cell acute lymphoblastic leukemia (T-ALL), 3 from Philadelphia chromosome positive ALL (Ph1+ALL), 8 from acute myeloblastic leukemia (AML), 3 from acute promyelocytic leukemia (APL), 8 from chronic myeloid leukemia at blast crisis (CML-BC), 3 from Burkitt's lymphoma and one from follicular cell lymphoma. The expression of CD80 or CD86 was frequent on cell lines derived from the patients with CML-BC or Burkitt's lymphoma, while it was rare on cell lines from T-ALL. Subsequently we analyzed the cells obtained from 48 patients with hematological malignancies, which consisted of 6 samples from patients with ALL, 30 from AML, 2 from CML-BC, 3 from B-cell lymphoma and one from each acute mixed leukemia (AMixL), adult T cell leukemia (ATL), T-cell large granular lymphocytic leukemia (T-LGL leukemia), chronic lymphocytic leukemia (CLL), myelodysplastic syndrome (MDS)-RAEB in T, multiple myeloma (MM) or T-cell lymphoma. Among all the 48 cases, all cases except one case with CLL and two with B cell lymphoma were demonstrated to be negative for CD80 on the neoplastic cells. CD86 and HLA-DR were shown to be expressed in 50% and 88% of total 48 cases respectively. In 30 AML samples, CD86 was positive in 15 cases (50%), which was sharply in contrast with the finding that CD80 was not detected in any AML samples. HLA-DR was expressed in 25 AML samples (83%). We also treated seven human hematopoietic cell lines with IFN-gamma, IL-12 or IL-15 and observed whether these cytokines could induce or enhance the expression of CD40, CD54, CD58 and HLA-DR as well as CD80 and CD86. The present study demonstrated that the expression of CD86 could be upregulated not only by IFN-gamma, but also by IL-12 or IL-15 in some cell lines. These findings suggested the possibility that the absence of CD80 on neoplastic cells may be associated with the lack of efficient anti-tumor immunity in most patients with hematological malignancies and that the immuno or immuno-gene therapy manipulating the expression of costimulatory molecules such as CD80 may be a useful treatment modality for hematological malignancies.

[Comparison of long-term survival between bone marrow transplantation and maintenance chemotherapy for adult acute lymphoblastic leukemia in first remission].

To clarify the efficacy of allogeneic bone marrow transplantation (BMT) for adult ALL in first remission we retrospectively studied long-term outcomes of adult ALL patients of age between 15 and 44 years who were treated in our institute from 1980 to 1990. In this period thirteen patients with HLA compatible donors were offered allogeneic BMT during the first remission, while 16 patients without HLA-compatible donor were treated with maintenance chemotherapy (Cancer Chemoth Pharmacology 33:359-365, 1994). Patient and disease characteristics (age, leukocyte count at presentation, immunophenotype, Ph1 chromosome, and duration to first remission) in the two groups were not significantly different (chi-square test p > 0.1). As causes of treatment failure, relapse was 90% for chemotherapy while relapse and therapy-related death were 67% and 33%, respectively, for transplantation. The leukemia-free survival (LFS) rates at 10 years were 52 +/- 13% for transplantation and 30 +/- 11% for chemotherapy (P > 0.2, g-Wilcoxon, Logrank). The 10-year-LFS rates of Ph1-negative patients of 15 to 29 year-old were 67 +/- 15% for transplantation (n = 9) and 62 +/- 15% for chemotherapy (n = 8) (P > 0.9). Although the present data are derived from a non randomized retrospective study and a relatively small number of patients, this study revealed no superiority of BMT over chemotherapy for the prolongation of first remission in adult ALL, especially, in a standard risk group such as young patients without Ph1 chromosome.

Early gastric cancer manifested as brain metastasis: report of a case.

A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis.

Effects of transfection of p210bcr-abl and bcr-v-abl into the factor-dependent human leukemia cell line HSM-911.

In order to clarify the action of the bcr-abl, a growth factor dependent human leukemic cell line (HSM-911) was transfected with p210bcr-abl or bcr-v-abl by electroporation. The cells transfected with bcr-v-abl, but not the cells transfected with p210bcr-abl, became growth factor independent. Some clones of the cells transfected with p210bcr-abl demonstrated cellular maturation (nuclear segmentation, becoming positive for naphthol ASD chloroacetate esterase, the disappearance of CD34 expression and the appearance of glycophorin A and CD10 expression). Moreover, these clones transfected with p210bcr-abl demonstrated apoptosis (increased expression of Fas and DNA ladder formation suggesting apoptotic DNA fragmentation). These findings demonstrated the different actions of p210 bcr-abl and bcr-v-abl, the former of which gave the cells the characteristics of maturation like the cells from chronic myelogenous leukemia, and the latter of which rendered the cells grow autonomously.

Bile peritonitis due to a spontaneous perforation of the common bile duct: report of a case.

Spontaneous perforation of the extrahepatic bile duct is rare. We herein report the case of an 80-year-old woman who underwent emergency laparotomy for bile peritonitis due to a spontaneous perforation of the common bile duct. A 2-mm perforation was found in the posterior wall of the choledochus, and its wall was paper-thin. Three stones, 2mm in diameter, were removed from the common bile duct. She underwent T-tube decompression with intraoperative cholangiography demonstrating a swollen papilla of Vater. The swelling of the papilla disappeared 4 weeks after the operation. Her postoperative course was uneventful. It seems likely that the elevated intraductal pressure due to the swollen papilla following stone impaction caused the perforation in this patient. Furthermore, the excessive friability of the common bile duct of unknown etiology may also have contributed to the perforation. This experience along with a review of the literature indicate that biliary decompression is the treatment of choice for this condition.

[Essential thrombocythemia in transformation to smouldering megakaryoblastic leukemia with myelofibrosis].

Leukemic transformation in essential thrombocythemia (ET) is rare. We describe a patient with ET which transformed to megakaryoblastic leukemia with myelofibrosis after treatment with melphalan for 8 years. His course after transformation smouldered for 20 months without antileukemic chemotherapy. A 61-year-old man was referred by a local doctor to Niigata University Hospital due to nasal bleeding in June 1984. Complete blood count (CBC) was as follows; hemoglobin 12.4 g/dl, platelets 268.8 x 10(4)/microliters, and white blood cells 11,900/microliters, with differentials of 39% PMN, 1% basophils, 2% eosinophils, 4% monocytes, and 13% lymphocytes. Bone marrow examination revealed hyperplasia of megakaryocytes without increase of reticulin fibers. Neutrophil alkaline phosphatase activity and karyotype of marrow cells were normal. ET was diagnosed. He was followed up by local doctor. The platelet count was controlled at a level of approximately 40 x 10(4)/microliters with melphalan for eight years. In January 1992 he developed pain in his lower extremities. He was admitted to our hospital on May 29, 1992. CBC was as follows; hemoglobin 8.9 g/dl, platelets 14.3 x 10(4)/microliters, and white blood cells 3,500/microliters, with differentials of 25% PMN, 5% monocytes, 28% lymphocytes, and 24% blasts. Bone marrow aspiration was unsuccessful and bone marrow biopsy revealed increases in fibroblasts and collagen fibers. Circulating blasts were positive for CD4, CD7, CD25, CD13, CD33, CD34, and HLA-DR and partly positive for CD41 and CD36. In ultrastructural cytochemistry blasts were positive for platelet peroxidase but negative for myeloperoxidase. Cytogenetic study revealed 46, XY, +der (1) t(1:7) (p11;q11) in all of five metaphases. He was diagnosed with megakaryoblastic leukemia accompanied by myelofibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Substitution of Val for Met at residue 239 of platelet glycoprotein Ib alpha in Japanese patients with platelet-type von Willebrand disease.

Genomic DNA was studied from four patients with platelet-type von Willebrand disease (vWD) from two Japanese families previously reported. The entire coding region of platelet glycoprotein (GP) Ib alpha, a component of the platelet receptor for von Willebrand factor (vWF), was examined by polymerase chain reaction (PCR) followed by direct DNA sequence analysis. A single point mutation was found in all patients resulting in substitution of Val (GTG) for Met (ATG) at residue 239 of GPIb alpha. All patients were heterozygous for the mutation, whereas none of the unaffected family members had an amino acid substitution at residue 239. Because the nucleotide substitution destroys an NIa III restriction site on GPIb alpha, PCR products were subjected to digestion with this enzyme; DNA fragments from both normal and mutant alleles were detected in all affected individuals. In allele-specific PCR, DNA was amplified from patients' genomic DNA using either adenine- or guanine-containing primers, whereas only adenine-containing primer successfully amplified DNA from normal individuals. Cloning of amplified DNA into bacteriophage M13mp19 and subsequent DNA sequence analysis confirmed the mutation in these families. The absence of the amino acid substitution at residue 239 of GPIb alpha in the normal individuals tested, together with the linkage of this substitution to the phenotypic expression of disease in these two families and in a family recently described suggest that this amino acid change is a molecular basis for platelet-type vWD, and the substitution may produce a quite similar phenotype to the one reported previously (Gly to Val at residue 233 of GPIb alpha).

Transfection of the bcr/abl oncogene into factor-dependent cells by electroporation: acquisition of autonomous proliferation.

In order to clarify the function of P210 bcr/abl oncogene in leukemogenesis, IL-3 dependent murine hematopietic cell line, FDC-P2, was transfected with the plasmid containing cDNA of P210 bcr/abl oncogene (pGD'210) or murine IL-3 (pcDmIL3) by electroporation. Four out of five pGDH210 transfected clones as well as FDC-P2 transfected with pcDmIL3, acquired autonomous proliferation (i.e. lost the requirement for IL-3 supplementation). The expression of bcr/abl oncogene was weak in one clone, which remained dependent on IL-3. Unlike pcDmIL3 transfectants, which secrete IL-3 into the supernatant, IL-3 was not demonstrated in the culture supernatant of pGD'210 transfected FDC-P2. These finding suggest that P210 bcr/abl oncogene is directly associated with autonomous proliferation, which is the first process of leukemogenesis.

Prediction of the ability to purge clonogenic B cell lymphoma from normal BM in vitro by heat: their survival curves correspond to a curve reflecting mortality in humans.

To develop new purging regimens for ABMT the ability to predict potential for purging of tumor cells from BM is important. Since the sensitivity of human B cell lymphoma to hyperthermia is not known, we examined its effect on the growth of B cell lymphoma cell lines (Raji and Daudi) in vitro to evaluate potential for purging clonogenic tumor cells from normal marrow by heat, using a limiting dilution assay to measure log depletion of tumor cells in a 20-fold excess of normal BM. When exposed to heat (42-43 degrees C) for 120 min, both clonogenic Raji and Daudi cells were dramatically reduced (a 4-to-6 log reduction) with time, whereas at 42 degrees C over half and at 43 degrees C 10% of normal granulocyte-macrophage progenitor cells survived for the same time period. This high level of lymphoma cell depletion by heat correlated with that of immunologic and pharmacologic studies. In addition, these survival curves during heating were found to correlate with the Gompertz-Makeham formula--a law of human mortality. This formula may be useful in predicting the purging effect of heat. These results suggest that in vitro hyperthermia could be applied effectively for the elimination of residual, clonogenic lymphoma cells in autologous marrow grafts before ABMT.

Combination therapy with rhGM-CSF and rhEpo for two patients with refractory anemia and aplastic anemia.

Because GM-CSF possesses burst-promoting activity (BPA) and megakaryocyte colony-stimulating activity (Meg-CSF) as well as stimulating activity on granulocyte-macrophage progenitors, and erythropoietin (Epo) has thrombopoietin-like activity, the combination therapy of GM-CSF and Epo seems to be more effective for stimulating erythropoiesis and thrombocytopoiesis in patients with pancytopenia. For this reason, the combination therapy of recombinant human GM-CSF (rhGM-CSF) and rhEpo was performed in two patients with refractory anemia (RA) and aplastic anemia (AA). Epo-unresponsive anemia was remarkably improved by adding rhGM-CSF to Epo and the effect lasted for 1 1/2 months in a patient with RA, but severe anemia occurred again immediately after the discontinuation of Epo. The neutralizing antibodies against GM-CSF were not demonstrated at the phase when anemia re-progressed in this patient. In a patient with AA, anemia and thrombocytopenia, which were refractory to previous administration of rhGM-CSF, responded to the combined administration of GM-CSF and Epo. Although the effects were maintained for 3 1/2 months, the anemia and thrombocytopenia became worse again after the administration of rhGM-CSF was changed from daily to every other day. These findings suggest the usefulness of combination therapy of GM-CSF and Epo for patients with pancytopenia.

Gene introduction into granulocyte-macrophage progenitor cells by electroporation: the relationship between introduction efficiency and the proportion of cells in S-phase.

Our previous study demonstrated the positive relationship between the gene introduction rate into hematopoietic cell lines by electroporation and the percentage of cells in S-phase. In the present study, granulocyte-macrophage progenitor cells (CFU-C) rich marrow cell fraction were cultured in suspension with IL-3, GM-CSF and G-CSF for 4 days. The number of CFU-C were increased three times after the culture, and 3H-thymidine suicide tests of cultured cells demonstrated that the proportion of CFU-C in S-phase was increased by two to four times. The efficiency of gene transfer into CFU-C with the plasmid pMoZtk (containing the beta-galactosidase gene) by electroporation was nearly doubled by culturing marrow cells with these growth factors. These findings confirm that the introduction rate of the gene into CFU-C by electroporation is more efficient in cell populations with a higher percentage of CFU-C in S-phase.

Alpha-interferon broadens the difference between surviving fractions of normal and leukemic progenitor cells in vitro by heat: its application to marrow purging.

Alpha-interferon (IFN) may inhibit the proliferation of human leukemic progenitor cells (L-CFU) in vitro and enhance the anti-tumor effects by heat. In this study, the combined effects of IFN and hyperthermia on the growth of L-CFU and human granulocyte-macrophage progenitors (CFU-GM) were examined to determine if this combination resulted in a greater selective killing of L-CFU than that obtained by heat treatment alone. The survival of normal CFU-GM without IFN decreased at elevated temperatures (42-44 degrees C). However, IFN added during heating (42 and 43 degrees C) appeared significantly to protect against the hyperthermic killing of CFU-GM in vitro leaving over 50% of CFU-GM surviving. The optimal dose to protect CFU-GM in vitro dropped to a rather low dose (100 U/ml). On the other hand, the addition of IFN to leukemic cell suspensions enhanced the hyperthermic killing of myeloid leukemic cell lines (HEL and KG-1) as well as a T lymphoblastic cell line (CEM) in a dose-related manner. In addition, similar results were observed in the study of L-CFU from patients with acute myelogenous leukemia. These results suggest that IFN can be used to broaden the difference between surviving fractions of CFU-GM and L-CFU by heat. Thus, this combination could be applied effectively and safely for the elimination of residual clonogenic leukemic cells in autologous remission marrow graft before autologous bone marrow transplantation.