Role of Intercellular Communications in Breast Cancer Multicellular Tumor Spheroids After Chemotherapy

Tumor heterogeneity is an important feature that is especially involved in tumor aggressiveness. Multicellular tumor spheroids (MTS) may provide some benefits in different steps for investigation of the aggregation, organization, differentiation, and network formation of tumor cells in 3D space. This model offers a unique opportunity for improvements in the capability of a current strategy to detect the effect of an appropriate anticancer agent. The aim of this study was to investigate the cellular interactions and morphological changes following chemotherapy in a 3D breast cancer spheroid model. Distribution of the gap junction protein "connexin-43" and the tight junction protein "occludin" was investigated by immunohistochemistry. Cellular interactions were examined by using transmission and scanning electron microscopies as well as light microscopy with Giemsa staining after treating cells with doxorubicin, docetaxel, and doxorubicin/docetaxel combination. Statistical analyses showed significant changes and various alterations that were observed in all groups; however, the most prominent effect was detected in the doxorubicin/docetaxel combination group. Distinct composition as a vessel-like structure and a pseudoglandular pattern of control spheroids were detected in drug-administered groups. Immunohistochemical results were consistent with the ultrastructural changes. In conclusion, doxorubicin/docetaxel combination may be more effective than the single drug usage as shown in a 3D model. The MTS model has been found to be an appropriate and reliable method for the detection of the changes in the expression of cellular junction proteins as well as other cellular proteins occurring after chemotherapy. The MTS model can be used to validate the effects of various combinations or new chemotherapeutic agents as well as documentation of possible mechanisms of new drugs.

Effect of apoptosis and response of extracellular matrix proteins after chemotherapy application on human breast cancer cell spheroids

Multicellular tumor spheroid (MTS) represents a three-dimensional structural form of tumors in laboratory conditions, and it has the characteristics of avascular micrometastases or intervascular spaces of big tumors. Recent studies indicate that extracellular matrix (ECM) proteins play a critical role in tumor metastasis, therefore normal and cancer cells require an ECM for survival, proliferation and differentiation. Doxorubicin and Docetaxel are widely used in the therapy of breast cancer, as well as in in vivo and in vitro studies. In this study, we examined the effect of apoptosis and proliferation of cells on the human breast cancer cell line, MCF-7, by using p53, bcl-2 and Ki67 gene expression, and the tendency to metastasis with extracellular matrix proteins, laminin and type IV collagen after chemotherapy in the spheroid model. The apoptotic cell death in situ was detected by TUNEL method. TUNEL-positive cells and positive immunoreactivities of laminin, type IV collagen, p53 and, bcl-2 were detected in the control group. There was no laminin and type IV collagen immunoreactivities in spheroids of drug groups. While TUNEL-positive cells and p53 immunoreactivity were detected in Docetaxel, Doxorubicin and Docetaxel/Doxorubicin groups, p53 immunoreactivity was not observed in the Docetaxel group. There was no bcl-2 immunoreactivity in either drug group. In addition, we did not detect Ki67 immunoreactivity in both control and drug treatment groups. However, the absence of Ki67 protein in MCF-7 breast multicellular tumor spheroids is possibly related to the cells in G0 or S phase. These chemotherapeutic agents may affect the presence of ECM proteins in this in vitro model of micrometastasis of spheroids. These findings suggest that the possible mechanism of cell death in Doxorubicin and Docetaxel/Doxorubicin treatment groups is related to apoptosis through the p53 pathway. However, we considered the possibility that there is another control mechanism for the Docetaxel group.

Evaluation of the relationship between inducible nitric oxide synthase (iNOS) activity and effects of melatonin in experimental osteoporosis in the rat

Inducible nitric oxide synthase (iNOS) plays a critical role in the pathogenesis of osteoporosis. iNOS generates nitric oxide (NO), a free radical contributing to the imbalance between bone formation and resorption caused by estrogen depletion. Melatonin is the major product of the pineal gland which is known to diminish iNOS expression and NO production significantly. The aim of this study was to determine the distribution of iNOS and the amount of apoptotic cells after melatonin treatment in ovariectomized rats. Since previous studies have shown that constitution of bone formation is primarily sustained in nucleus pulposus and epiphyseal cartilage, experiments were carried out on nucleus pulposus and epiphyseal cartilage; additional quantitation of osteoblasts and osteoclasts were evaluated on vertebral area as well. Vertebral sections of ovariectomized rats were obtained from formalin-fixed and parafin-embedded blocks. iNOS expression and quantitation of apoptotic cells in nucleus pulposus and epiphyseal cartilage were evaluated using indirect immunoperoxidase and TUNEL techniques, respectively. The number of osteoclasts and osteoblasts in trabecular bone was determined using histomorphometry. Ovariectomy increased iNOS expression and the number of apoptotic cells in nucleus pulposus and epiphyseal cartilage, whereas a 4-week treatment with melatonin (10 mg/kg/day) resulted in the reduction of both effects. These data indicate that there is strong influence of melatonin application on expression of iNOS, apoptosis, osteoclast and osteoblast numbers after ovariectomy. In conclusion, melatonin besides its usual use as an antiaging hormone, may also be an effective hormone in treatment of bone changes in estrogen deficiency states.

Assessment of effects of pinealectomy and exogenous melatonin administration on rat sciatic nerve suture repair: an electrophysiological, electron microscopic, and immunohistochemical study

BACKGROUND

Collagen scar formation at the cut end of a nerve, an important problem in clinical practice for neurosurgeons in peripheral nerve surgery, obstructs sprouting of axons into appropriate distal fascicles, and thereby limits nerve regeneration. Researchers attempt to control collagen accumulation in the formation of neuroma by various physical and chemical methods, but these have yielded only limited functional success. This is the first experimental study investigating the effects of melatonin (MLT) on nerve repair and neuronal regeneration in rat sciatic nerve suture repair.

METHODS

The hypothesis that exogenous MLT administration may inhibit the formation of neuroma in peripheral nerve surgery was investigated in rat sciatic nerve model. In this study, a total of 80 rats were used for control groups (Groups Ia, Ib, IIa, and IId), MLT group (Group Ic), surgical pinealectomy (Px) groups (Groups IIb and IIc), and group of MLT treatment following Px procedure (Group IIe). All animals underwent a surgical intervention consisting of bilateral sciatic nerve section and primary suture repair. At 8 weeks after repair, the animals were killed following completion of recording of nerve action potentials (NAPs). Then, unilateral sciatic nerve specimens including the suture repair region were carefully removed and the excised segments were processed for electron microscopy examination. Afterwards, contralateral sciatic nerve specimens from two animals from each group were removed and stained for immunohistochemical analysis.

RESULTS

Results of morphometric analysis revealed that Px procedure caused an elevation of collagen content of the sciatic nerve and macroscopic neuroma formation, and that there was a statistically significant reduction in collagen content of the same region in pinealectomized animals treated with MLT (p<0.001). Accordingly, electrophysiological findings demonstrated that the stimulus intensities required to excite a NAP response were increased in surgical Px group, but the presence of a reduced threshold response was found in the group treated with MLT following Px procedure (p<0.01). Immunohistochemical staining for Type I collagen and Type III collagen was markedly more intense in the epineurium of animals after Px. Virtually no or only weak staining was observed in animals in control groups and the MLT treatment group. Results of immunohistochemical analysis revealed that surgical Px procedure caused a strong immunoreactivity for Type I collagen and Type III collagen in all connective tissue planes of the nerve, especially in the epineurium, and there was a statistically significant reduction in immunoreactivity of the repair region in animals receiving MLT treatment after Px procedure (p<0.001).

CONCLUSION

This study demonstrates that exogenous MLT administration significantly inhibits collagen accumulation in the formation of neuroma in the suture repair site and thereby improves nerve regeneration. From a clinical standpoint, the positive effect of MLT administration on neuroma formation and nerve regeneration seems a particularly attractive treatment option. Therefore, we believe that nerve repair with addition of MLT may be a worthwhile option in addition to other treatment modalities in case of MLT deficiency, such as aging. However, further experimental and clinical studies using functional analysis warranted to confirm this result in future.

Soluble adhesion molecules (sICAM-1, sL-Selectin, sE-Selectin, sCD44) in healthy allogenic peripheral stem-cell donors primed with recombinant G-CSF

BACKGROUND

We analysed the effects of rhG-CSF (Amgen-Roche, USA) on serum changes of four soluble adhesion molecules (SAM) (sICAM-1, sL-Selectin, sE-Selectin and sCD44) in healthy peripheral allogeneic stem-cell transplantation donors and their correlation with acute GvHD and effect on engraftment kinetics.

METHODS

Serum SAM of 15 consecutive healthy HLA identical-sibling donors (median age 30 years, male:female ratio, 7:8) were monitored using a commercial ELISA Kit (Bender Med, Austria) prior to, on the day of first apheresis and 24 h after the cessation of rhG-CSF (10 microg/kg/day s.c. on 5 days) administration. Leukapheresis was started on the fifth day of rhG-CSF administration, using a continuous-flow blood separator (Cobe Spectra, COBE BCT, Inc, Lakewood, CO). Apheresis cycles were continued daily until a target of 4.0 x 10(6) CD34(+) cells/kg was reached.

RESULTS

The results indicate a steady rise of sL-Selectin, sE-Selectin, and sCD44, but not of sICAM-1. Median number of mononuclear cells (MNC) and CD34(+) cells transfused were 7.7x 10(8)/kg and 6.0 x 10(6)/kg, respectively. There was a near-significant correlation between the sL-Selectin levels and CD34(+) cell yield (r = 0.49, 0.06). Median granulocyte and platelet engraftment days were 11 (10-18) and 12 (9-33), respectively. There was a significant inverse correlation between the CD34(+) cell dose and granulocyte levels (r = -0.68, p = 0.022), but not for platelet engraftment. The only correlation between SAM levels and engraftment was for sICAM-1 levels. Increasing sICAM-1 levels were a sign of prolonged neutropenia (r = 0.72, p = 0.011). No correlation between the apheresis day serum levels of adhesion molecules and acute GvHD was documented.

DISCUSSION

Analysis of sICAM-1, sL-Selectin, sE-Selectin and sCD44 levels during allogeneic PBSC apheresis did not reveal any significant effect on engraftment and GvHD, except the correlation of sL-Selectin levels and collected CD34(+) cells. More research and data about the role of not only SAM levels, but also antigenic expression of SAM are required to enlighten leukocyte-endothelial cell interactions and egress of stem cells during G-CSF administration.

Tuberculin responses in children with allergic diseases

BACKGROUND

The prevalence of allergic disorders has been increasing over the last 30 years, especially in developed countries. One factor associated with this rise may be the decline of many childhood infections. We investigated tuberculin responses in allergic children in order to see the development of delayed-type hypersensitivity reactions to tubercule bacillus infection.

METHODS

The study sample was composed of 106 allergic and 100 nonallergic children vaccinated with bacille Calmette-Guerin (BCG). The standard Mantoux test was applied to all children. The reactions were read after 72 h by measuring the diameter of the wheal.

RESULTS

The wheal size was 6.29 +/- 5.09 mm (mean +/- SD) in allergic children, and 2.79 +/- 2.96 mm in nonallergic children. The difference between the two groups was significant (P < 0.001). In children with a single BCG scar, the mean purified protein derivative (PPD) wheal size for allergic children was 4.77 +/- 4.79 mm, and for nonallergic children it was 2.48 +/- 3.19 mm. The mean PPD wheal sizes in allergic and nonallergic children who had been vaccinated twice were 8.35 +/- 4.80 mm and 3.33 +/- 2.44 mm, respectively. This difference was statistically significant (P < 0.05). In 27.35% of the allergic children and 6% of the nonallergic children, the positive tuberculin responses (PPD > or = 10 mm) were recorded. The difference was significant (P < 0.05).

CONCLUSIONS

Our results showed that response to tuberculin in BCG-immunized allergic children is higher than in BCG-immunized nonallergic children.

Allogeneic hematopoietic cell transplantation without myeloablative conditioning for patients with advanced hematologic malignancies

BACKGROUND

The effect of allogeneic hematopoietic cell transplantation (alloHCT) on hematologic malignancies is based on the graft-versus-malignancy effect. Obtaining this effect with reduced toxicity has been possible by non-myeloablative (NMA) alloHCT. Once mixed chimeric status, and host versus graft with graft versus host tolerance are achieved, further strengthening of chimerism and graft-versus-malignancy effect can be obtained by donor lymphocyte infusions (DLIs) when needed.

METHODS

The patient group consisted of 13 patients with advanced hematological malignancies: seven had CML, four of them in blastic-, two in chronic- and the remainder in accelerated-phase; four patients with AML, refractory or in second remission state; one patient with primary refractory secondary AML; and one patient with ALL relapsed after alloHCT. Conditioning regimen consisted of fludarabine 30 mg/m(2)/day for 6 days and anti-T-lymphocyte globulin (ATG) 10 mg/kg/day for 4 days as immunosuppressive. Ara-C or Bu or melphalan were used as the cytoreductive component. All transplants were performed using HLA-identical sibling donors' peripheral blood hematopoietic cells, after priming with filgrastim. Post-transplant GvHD prophylaxis was achieved with CsA alone in 10 patients, and with CsA plus mycophenolate mofetil in the last three patients.

RESULTS

Median follow-up is 3 months (range, 0-20) for all the patients and 6 months (range, 2-15) for the live patients. Donor chimerism was shown in 10 patients, not regarding any pretransplant feature. DLIs were performed in seven patients after transplantation and two of them achieved complete chimeric status and molecular remission. Two CML patients in blastic phase (CML-BP), and the primary refractory secondary AML patient did not respond to procedure. In four patients, drug therapy in conventional doses was added to post-transplant DLIs for their relapsed or refractory diseases. Two patients with AML in second CR, and another CML-BP patient, relapsed or progressed after transplantation. A patient with CML-BP achieved CR and full donor chimerism after transplantation, but developed refractory post-transplant lymphoproliferative disease in the 19th month. Two patients with refractory AML, one patient with relapsed ALL and two patients with CML in chronic phase were in complete chimeric status and free of disease signs. Acute GvHD, Grade II-III, was observed in five patients, and two of them developed secondary progressive chronic GvHD subsequently. We observed one early death in a platelet transfusion refractory blastic phase CML patient due to intracranial hemorrhage. Procedure-related severe toxicity was not observed, either in standard-risk patients or stem-cell donors.

DISCUSSION

Establishing engraftment with donor chimerism was the first successful step in this approach. The second step, which was the result of the graft-versus-malignancy effect, could be seen in most of the patients, but was not sustained in all of them because of the aggressiveness of their malignancy. It can be suggested that the immunotherapeutic efficacy of this approach could be more successful, and with acceptable toxicity, when performed in patients with minimal residual disease. The role of NMA conditioning, and of the treatment in standard disease indications, remains to be determined in further studies.

Detection of antibodies to Borna disease virus (BDV) in Turkish horse sera using recombinant p40. Brief report

The nucleoprotein of Borna disease virus (BDV-p40) was produced in a Baculovirus expression system using sf9 cells. The purity and specificity of the recombinant p40 was confirmed by SDS-PAGE and immunoblotting. The recombinant p40 was used in an ELISA to screen horse sera in Turkey. For this, 323 horses from selected cities in the Marmara region of Turkey were examined clinically and serum was collected from each. All horses were clinically healthy except for a few with wounds on the skin. Antibodies to BDV were detected in the sera of 82 (25%) of 323 horse sera. Six sera were selected that had low, medium or high OD values by ELISA and were analysed by Western blotting. All reacted specifically with p40 at a dilution of 1 in 1000. This is the first report of the detection of Borna disease in Turkey and needs further molecular biological investigations to compare the Turkish strains with those strains detected in Europe.

Mutations of the 5alpha-steroid reductase type 2 gene in six Turkish patients from unrelated families and a large pedigree of an isolated Turkish village

We describe six Turkish patients with 5alpha-steroid reductase type 2 deficiency from unrelated Turkish families and a large pedigree of one of these patients who reside north-west of Anatolia. Patients NA, KS, BD and SY presented for evaluation of bilateral inguinal masses with female phenotypes. Patient ABE had penoscrotal hypospadias with male phenotype. Homozygous mutation of the 5alphaSR2 gene was identified in five of these patients by genomic DNA analysis. These mutations were Leu55Gln in exon 1 (in patients FG, BD and ABE), deltaMet157 in exon 3 (in patient NA), and splice junction abnormality in intron 1 (in patient SY). One individual (patient KS) was found to be a compound heterozygous carrier of two different mutations, Leu55Gln in exon 1 and Arg171Ser in exon 3. Patient FG had a large pedigree with the Leu55Gln mutation in exon 1. The pedigree of this family with marital consanguinity is remarkable, and possibly due to the isolation of this family because of economic and social problems. A further 85 individuals belonging to this family were analyzed for exon 1 Leu55Gln mutations in the 5alphaSR2 gene. Forty-two of these 85 individuals (49.41%) had this alteration; 11 were homozygous (8 genetic male, 3 genetic female) and 31 heterozygous (18 genetic male, genetic female) for this mutation. It was interesting to see asymptomatic homozygous female carriers. In conclusion, according to our results and those of other Turkish patients reported by different investigators, 5aSR2 gene mutation analysis, especially for Leu55Gln in exon 1 and deltaMet157 in exon 3, must be carried out in Turkish patients with male pseudohermaphroditism. Homozygous asymptomatic female carriers must be taken into consideration in this clinical entity, especially in a closed population, because of the risk of transmitting the disease to their offspring.

CD41+ and CD42+ hematopoietic progenitor cells may predict platelet engraftment after allogeneic peripheral blood stem cell transplantation

The objective of this study was to quantify subpopulations of CD34+ cells such as CD41+ and CD42+ cells that might represent megakaryocyte (MK) precursors in peripheral blood stem cell (PBSC) collections of normal, recombinant human granulocyte-colony stimulating factor (rhG-CSF) primed donors and to determine whether there is a statistical association between the dose infused megakaryocytic precursors and the time course of the platelet recovery following an allogeneic PBSC transplantation. Twenty-six patients with various hematologic malignancies transplanted from their HLA identical siblings between July 1997 and December 1999 were used. All patients except one with severe aplastic anemia who had cyclophosphamide (CY) alone received busulfan-CY as preparative regimen and cyclosporine-methotrexate for GVHD prophylaxis. Normal healthy donors were given rhG-CSF 10 microg/kg/day subcutaneously twice daily and PBSCs were collected on days 5 and 6. The median number of infused CD34+, CD41+ and CD42+ cells were 6.61 x 10(6)/kg (range 1.47-21.41), 54.85 x 10(4)/kg (5.38-204.19), and 49.86 x 10(4)/kg (6.82-430.10), respectively. Median days of ANC 0.5 x 10(9)/L and platelet 20 x 10(9)/L were 11.5 (range 9-15) and 13 (8-33), respectively. In this study, the number of CD41+ and CD42+ cells infused much better correlated than the number of CD34+ cells infused with the time to platelet recovery of 20 x 10(9)/L in 26 patients receiving an allogeneic match sibling PBSC transplantation (r = -0.727 and P < 0.001 for CD41+ cells, r = -0.806 and P < 0.001 for CD42+ cells, r = -0.336 and P > 0.05 for CD34+ cells). There was an inverse correlation between the number of infused CD41+ and CD42+ cells and duration of platelet engraftment. Therefore, as the number of CD41+ and CD42+ cells increased, duration of platelet engraftment (time to reach platelet count of > or = 20 x 10(9)/L) shortened significantly. Based on this data we may conclude that flow cytometric measurement of CD41+ and CD42+ progenitor cells may provide an accurate indication of platelet reconstitutive capacity of the allogeneic PBSC transplant.

Mobilization of peripheral blood stem cells with chemotherapy and recombinant human granulocyte colony-stimulating factor (rhG-CSF): a randomized evaluation of different doses of rhG-CSF

To date, no randomized study has compared different doses of recombinant human granulocyte colony-stimulating factor (rhG-CSF) following submyeloablative mobilization chemotherapy. Therefore, we evaluated the effect of different doses of rhG-CSF following mobilization chemotherapy on yields of CD34+ peripheral blood stem cells (PBSC). Fifty patients were randomized to receive 8 (n = 25) versus 16 microg/kg/d (n = 25) of rhG-CSF following mobilization chemotherapy. The median number of CD34+ cells collected after 8 microg/kg/d of rhG-CSF was 2.36 x 10(6)/kg (range, 0.21-7.80), compared with 7.99 (2.76-14.89) after 16 microg/kg/d (P < 0.001). Twenty out of 25 (80%) patients in the low-dose and 23 out of 25 (92%) in the high-dose rhG-CSF arm underwent high-dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT). Median days to white blood cell engraftment in patients mobilized with 8 microg/kg and 16 microg/kg of rhG-CSF were 12 (10-20) and 9 (8-11) respectively (P < 0.001). There was no difference between the two groups regarding the other parameters of peritransplant morbidity: days to platelet engraftment (P = 0.10), number of red blood cell (P = 0.56) and platelet transfusions (P = 0.22), days of total parenteral nutrition requirement (P = 0.84), fever (P = 0.93) and antibiotics (P = 0.77), and number of different antibiotics used (P = 0.58). These data showed that higher doses of rhG-CSF following submyeloablative mobilization chemotherapy were associated with a clear dose-response effect based on the collected cell yields. Based on the parameters of peritransplant morbidity, 8 microg/kg/d was as effective as 16 microg/kg/d except for a rapid neutrophil engraftment in the high-dose arm. Therefore, in routine clinical practice, despite some advantage in the use of higher doses of rhG-CSF, lower doses may be used for PBSC collections following chemotherapy-based mobilization regimens in this cost-conscious era.

Benthic community structure of the Bosphorus and surrounding area

Abstract Spatial and temporal distribution of benthic communities around the Strait of Istanbul (Bosphorus) and the effect of lower layer discharge on these communities have been evaluated during studies between February-December 1999. Mytilus galloprovincialis was the dominant species with fasies at the Black Sea station that is not affected by the strait lower layer current system. On the other hand, another Black Sea station, influenced by the strait lower layer currents, has a similar biota to the strait stations. Species richness and diversity is highest in the strait than other areas. The dominant species is Maera grossimana. However, the station located at the Black Sea exit of the strait has a different biota, and various groups/species appeared to be dominant. Melinna palmata is the dominant species at the Sea of Marmara during the study period. Low dissolved oxygen values of lower layer and soft substratum of sediment resulted in wide distribution of Melinna palmata, adapted to these conditions. The closer stations to the strait in the Sea of Marmara have higher diversity as a result of hydrodynamic processes. On the other hand, coastal stations with low currents and inputs have lower index values, showing the negative effect of discharges and pollution.

Consecutive IL-2 and IFN-a2a Maintenance in a Patient with Acute Non-lymphoblastic Leukemia and Renal Cell Cancer

Over the last few years, the use of ınterleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells have been found to be effective in the treatment of some solid tumours and acute myeloid leukemia. Our patient was initially diagnosed as having bilateral synchronous renal cell cancer (RCC) and underwent nephrectomy. Approximately two years after the operation he developed leukopenia without any sign of residual renal cell cancer. Bone marrow examination revealed acute myeloblastic leukemia (AML). IL-2 following IFN-a2a was used as a maintenance therapy after a standard remission induction and a consolidation therapy. Our patient has been still disease free for 58 months after the diagnosis of AML and 71 months after the diagnosis renal cell cancer. Review of the literature showed that this is the first case who has both RCC and AML and was treated successfully with IL-2 and IFN-a2a.

Effects of defibrotide on aorta and brain malondialdehyde and antioxidants in cholesterol-induced atherosclerotic rabbits

The effects of a high-cholesterol diet in the presence and absence of defibrotide, a single-stranded polydeoxyribonucleotide compound, on the lipid peroxidation product malondialdehyde, endogenous antioxidant enzymes catalase, glutathione peroxidase, and the antioxidant thiol compound GSH were investigated. Forty male New Zeland white rabbits were divided into four groups each consisting of 10 rabbits. Group I received a regular rabbit chow diet and group II 1% cholesterol plus regular chow, group III was given defibrotide (60 mg/kg per day p.o. in water) and was fed with regular chow, and group IV received defibrotide plus 1% cholesterol for 9 weeks. Blood cholesterol and malondialdehyde, catalase, glutathione peroxidase, and GSH were determined before starting the experimental diet regimen (basal). After 9 weeks, the same parameters were determined in blood, aorta, and brain tissues (end -experiment). Aortic tissue was examined under a light microscope for morphological alterations indicative of atherosclerosis. The increase in serum total cholesterol was greater in group II than group IV. Plasma malondialdehyde in group II was higher than in group III. Brain malondialdehyde in group II was higher than all other groups, and aortic malondialdehyde in this group was higher than group I and III. Serum catalase activity decreased in group II and increased in group III, compared with basal values. Brain catalase activity in group I was higher than group II, and aorta catalase in group IV was higher than in group I and III. Blood glutathione peroxidase activity in group III and IV was higher than basal. GSH concentrations decreased significantly in the cholesterol-fed groups (group II and IV). Histological alterations in the cholesterol-fed groups were more pronounced in group II. The increased levels of malondialdehyde in plasma, aorta, and brain tissue of group II suggest a role of oxygen free radicals in the pathogenesis of cholesterol-induced atherosclerosis. The higher malondialdehyde values in the brain tissues of animals in group II compared with group IV suggest a protective role of defibrotide in the brain against lipid peroxidation in the oxidant stress of cholesterol-induced atherosclerosis. Increased catalase activities in the blood and aortic tissues and increased glutathione peroxidase activities in the blood of rabbits receiving defibrotide suggest an induction of these antioxidant enzyme activities by defibrotide. These results imply that anti-atherosclerotic, anti-ischemic effects of this drug may be due to the beneficial effects on the oxidant-antioxidant balance of various tissues.

Recombinant human granulocyte colony-stimulating factor (rh-G-CSF) may accelerate hematopoietic recovery after HLA-identical sibling allogeneic peripheral blood stem cell transplantation

We studied the effects of recombinant human granulocyte colony-stimulating factor (G-CSF) on hematopoietic recovery and clinical outcome in patients undergoing allogeneic peripheral blood stem cell (PBSC) transplantation. Fifty-six patients with hematological malignancies who underwent allogeneic PBSC transplantation between 1995 and 1998 were entered into this study. Twenty-eight patients who received daily G-CSF from day +1 after allogeneic PBSC transplantation until the absolute neutrophil count (ANC) reached >0.5 x 10(9)/l for 3 consecutive days were compared with 28 patients (control group) who did not receive G-CSF in a non-randomized manner. The study group and the control group were comparable with respect to baseline patient and transplantation characteristics. Median times to ANC of >0.5 x 10(9)/l and 1 x 10(9)/l with or without G-CSF were 12 days (range 8-21), 13 days (10-32) (P = 0.04) and 13 days (9-21), 15 days (11-44) (P = 0.02), respectively. Median times to reach a platelet count of >20 x 10(9)/l with and without G-CSF were 11 days (0-20) and 13 days (9-26), respectively (P = 0.03). The incidence of febrile episodes was significantly lower with G-CSF, 75% vs 100% (P = 0.008). Patients receiving G-CSF had less grade III-IV mucositis than those who did not receive G-CSF (P = 0.01). There was also no increase in the incidence and severity of acute GVHD in patients using G-CSF (P = 0.22). Although the number of relapsing patients was greater in the G-CSF group (seven vs three patients), this was not statistically significant (P = 0.24). Disease-free and overall survival rates did not differ between the two groups (P = 0.58 and 0.53, respectively). The administration of G-CSF after allogeneic PBSC transplantation provided faster neutrophil and platelet engraftment associated with less severe mucositis and less febrile episodes.

The effect of G-CSF on lymphocyte subsets and CD34+ cells in allogeneic stem cell transplantation

The effect of granulocyte colony-stimulating factor (G-CSF) on peripheral blood lymphocytes (PBL) and CD34+ cell frequency in the apheresis product has been determined in 25 healthy stem cell donors. Peripheral blood mononuclear cells (PBMNC) were collected after five days of G-CSF 10 microg/kg/day s.c., which was well tolerated. The median number of leukocytes increased eight-fold over that of pretreatment levels. Collection of PBMNC lasted a median of two (range, 1-3) days. The mean mononuclear cell (MNC) count and total lymphocyte percentage were 6.69 x 10(8)/kg and 59.08%, respectively, and the frequency of CD34+ cell expression was 2.1% in the apheresis product. The frequency of CD3+, CD4+, CD25+, NK and CD122+ cell expressions in mobilized PBMNC and PBL showed no significant difference. However, the frequency of CD8+, CD8+28+, CD3+DR+, CD19+, CD20+ and CD22+ B cells expression in the apheresis product increased significantly compared to steady-state PBL. In contrast, the frequency of the CD11 a+ and CD8+38+ cell expressions in the apheresis product was decreased compared to the steady-state PBL. The mean yield of CD34+ and CD3+ cells were 13.6 x 10(6) and 2.69 x 10(8)/kg of recipient body weight (RBW), respectively. Following allograft all patients engrafted with >0.5 x 10(9)/l neutrophil and < or = 20 x 10(9)/l platelets on a median of day 13 and 12, respectively. Nine patients had grade II-IV acute GVHD and chronic GVHD occurred in eight patients. Four patients died due to transplant-related complications. There was one late engraftment failure which occurred on the fifth month. Thirteen patients are still alive. In conclusion, these results indicate that administration of G-CSF at 10 microg/kg/day in normal donors alters the lymphocyte subsets and there are significant differences in the lymphocyte contents of the recipients before apheresis and in apheresis product.

Allogeneic peripheral blood stem cell transplantation for severe aplastic anemia

Allogeneic peripheral blood stem cell transplantation (PBSCT) is rarely applied for the treatment of severe aplastic anemia (SAA) because of questionable durability of engraftment and increased risk of graft versus host disease (GVHD). We performed allogeneic PBSCT in 3 SAA patients from their human leukocyte antigen (HLA)-identical siblings. One received bone marrow after conditioning with cyclophoshamide (Cy) plus antithymocyte globulin. He had a second transplant with peripheral blood stem cells from the original donor because of a graft failure (GF). Two other patients received PBSCT as a first option, with Cy as the only conditioning drug. The 3 patients received short-term methotrexate and cyclosporine as a postgrafting immunosupression. In the latter 2 cases, no GF has been observed, and a successful and complete hematological recovery was achieved and maintained for 28 and 25 months, respectively. In conclusion, PBSCT provides a quick and complete hematological recovery in SAA patients.