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Biomedical subjects

S Rutella

Publications and source records attributed to S Rutella.

At least 19 recordsLinked to original sources
PubMed2007

Association between cutaneous melanoma, Breslow thickness and vitamin D receptor BsmI polymorphism.

BACKGROUND: Literature data report an association between some vitamin D receptor (VDR) polymorphisms and different kinds of tumours, including malignant melanoma (MM). Only three VDR polymorphisms (FokI, TaqI and A-1012G) have been investigated in association with the presence of cutaneous MM or the development of metastases. OBJECTIVES: The present paper analyses for the first time the association between BsmI polymorphism and MM prevalence together with Breslow thickness. In addition, the FokI single nucleotide polymorphism was also determined. METHODS: One hundred and one patients with MM and 101 healthy donors matched for age and sex were enrolled. Molecular VDR typing was performed by means of restriction fragment length polymorphism analysis. RESULTS: All cases and controls were in Hardy-Weinberg equilibrium for BsmI, FokI and A-1012G. Significant associations were found between the BsmI bb genotype frequency and MM (P = 0.02) along with Breslow thickness (P = 0.001). This same behaviour was not observed for the FokI or A-1012G polymorphisms. Multivariate logistic regression analysis confirmed these significant results after correction for age, gender, skin type and MM localization. CONCLUSIONS: Although the biological meaning of the effects exerted by BsmI polymorphism is still under debate, the statistical association found in the present study suggests that further work should be done to verify this variant as a possible risk marker for MM and its aggressiveness, also considering that the real association may be due to other unknown genes linked to the BsmI b allele.

Adult↗
PubMed2006

Defective platelet responsiveness to thrombin and protease-activated receptors agonists in a novel case of gray platelet syndrome: correlation between the platelet defect and the alpha-granule content in the patient and four relatives.

BACKGROUND: We report a novel case of gray platelet syndrome (GPS). A 14-year-old boy had bleeding diathesis, mild thrombocytopenia, giant platelets with severe defect of alpha-granule secretory proteins, myelofibrosis and splenomegaly. METHODS AND RESULTS: Platelet function studies showed a marked reduction of aggregation and Ca(2+) mobilization by thrombin, protease-activated receptor 1 (PAR1)-activating peptide (AP) and PAR4-AP, PAR1 expression at 55% of normal levels, and a more than two hundred fold reduction of in vitro whole-blood thromboxane B(2) (TXB(2)) production. Sequencing of coding regions of the PAR1 gene failed to show abnormalities. This patient was initially classified as a sporadic case of GPS, as electron microscopy failed to identify giant platelets and/or alpha-granule deficiency in his relatives. However, further studies on the father and three other relatives showed a relative lack of platelet alpha-granule proteins by immunofluorescence microscopy, a defective platelet response to PAR4-AP, and severely reduced in vitro whole-blood TXB(2) production. On this basis, we suggest that in this family, GPS was transmitted in a dominant fashion with highly variable penetrance. CONCLUSIONS: Our study suggests that current diagnostic criteria fail to identify some patients with a mild GPS phenotype and that such patients might be identified by the methods cited above. It also better characterizes the pathogenesis of defective platelet responses to thrombin, and raises interesting questions on the correlation between abnormal PAR function and the lack of alpha-granule content in GPS.

Adolescent↗
PubMed2006

Rescue therapy by portal infusion of autologous stem cells in a case of drug-induced hepatitis.

Recent efforts have been directed toward new therapeutic options to approach drug-induced hepatitis. We report a case of acute liver failure associated with Nimesulide in a 67-year-old man, with a medical history of chronic alcohol abuse. The biopsy was compatible with chronic alcoholic liver disease and acute drug-induced injury. The patient was enrolled to receive G-CSF followed by apheresis and selection of peripheral-blood stem cells. After ultrasound-guided injection of CD34+cells in the portal vein, we observed a rapid improvement of synthetic liver function, with particular reference to coagulation parameters. Liver biopsy performed 20 days after, showed wide areas of regeneration. In the next 30 days the laboratory signs of acute decompensation progressively improved. Unfortunately he died of multiple-organ failure related to bacterial infection. Intrahepatic injection of peripheral-blood stem cells seemed safe and produced good periprocedural results with improvement of synthetic profile, suggesting a possible role of stem cells in the regeneration process.

Aged↗
PubMed2006

Treatment of acute leukaemias with monoclonal antibodies: current status and future prospects.

Monoclonal antibodies are a new class of agents targeted at specific receptors on cancer cells. In addition to direct cellular effects, antibodies can carry substances to the targeted cells, such as radioactive isotopes, toxins, and antineoplastic agents. At present monoclonal antibodies, directed against both lymphoid antigens (CD 20 and CD 52) and a myeloid antigen (CD33) are available for clinical use. In ALL, rituximab, a humanized anti CD20 antibody, has been combined to chemotherapy mainly in mature B-ALL and Burkitt's lymphoma and preliminary results are promising. Alemtuzumab is an anti-CD52 humanized antibody, which showed anti-tumour activity in CLL; clinical effects were observed in some patients with relapsed adult ALL. Monoclonal antibodies against myeloid antigens have been prevalently used in acute myeloid leukaemias (AML), where the most utilised immunological target is CD33. The CD33 molecule is expressed by approximately 90% of AMLs but not on CD34(+) bone marrow-resident hematopoietic stem cells. The humanized anti-CD33 monoclonal antibody HuM195 has only modest activity against overt AML, but it can eliminate minimal residual disease. Radioimmunotherapy with beta-particle-emitting isotopes targeting CD33 shows a major efficacy. Targeted chemotherapy with the anti-CD33-calicheamicin construct gemtuzumab ozogamicin (GO) has produced remissions as a single agent in patients with relapsed AML and appears promising when used in combination with standard chemotherapy. GO is composed of a humanized immunoglobulin G(4) (IgG(4)) monoclonal antibody (mAb), targeting the CD33 antigen and linked to a calicheamicin derivative, a cytotoxic anthracycline antibiotic. GO has been approved by FDA as second-line therapy in older patients with AML. The most common adverse effects of monoclonal antibodies are myelosuppression, infusion-related reactions, and hypersensitivity reactions. Rituximab may cause tumour lysis syndrome. Alemtuzumab causes immunosuppression, increasing the risk of infection. GO may cause hepatotoxicity.

Acute Disease↗
PubMed2005

How does human stem cell therapy influence gene expression after liver injury? Microarray evaluation on a rat model.

BACKGROUND: Tissue homeostasis is guaranteed by stem proliferating reserve, depending on dynamic changes in gene expression. A high plasticity is shown by the haematopoietic stem cells, potential source for liver regeneration. AIM: We aimed to evaluate the gene expression modifications induced by human haematopoietic stem cell therapy after liver injury in rats. SUBJECTS: Rats were sorted as follows: (A) human-haematopoietic stem cell injection after allyl alcohol liver damage; (B) only haematopoietic stem cell injection; (C) only allyl alcohol injection; and (D) sacrifice without any treatment. METHODS: Livers, spleens and bone marrows were analysed with flow-cytometry. Livers were also studied by reverse-transcription PCR, histology, immunohistochemistry and microarray analysis; selected genes were confirmed by real-time PCR. RESULTS: In subset A, haematopoietic stem cells were selectively recruited by liver, with respect to the group B, and they improved the liver regeneration process compared to group C. As regards microarrays, haematopoietic stem cell infusion upregulates 265 genes and downregulates 149 genes. Differentially regulated genes belong to a broad range of functional pathways, including proliferation, differentiation, adhesion/migration and transcripts related to oval-cell activation. Real-time PCR validated array results. CONCLUSIONS: Our study confirmed the capacity of haematopoietic stem cells to contribute to liver regeneration. Moreover, microarray analysis led to the identification of genes whose regulation strongly correlates with a more efficient process of liver repair after haematopoietic stem cell injection.

Animals↗
PubMed2004

A human umbilical cord stem cell rescue therapy in a murine model of toxic liver injury.

BACKGROUND: Several studies have demonstrated that bone marrow contains a subpopulation of stem cells capable of participating in the hepatic regenerative process, even if some reports indicate quite a low level of liver repopulation by human stem cells in the normal and transiently injured liver. AIMS: In order to overcome the low engraftment levels seen in previous models, we tried the direct intraperitoneal administration of human cord blood stem cells, using a model of hepatic damage induced by allyl alcohol in NOD/SCID mice. METHODS: We designed a protocol based on stem cell infusion following liver damage in the absence of irradiation. Flow cytometry, histology, immunohistochemistry and RT-PCR for human hepatic markers were performed to monitor human cell engraftment. RESULTS: Human stem cells were able to transdifferentiate into hepatocytes, to improve liver regeneration after damage and to reduce the mortality rate both in both protocols, even if with qualitative and quantitative differences in the transdifferentiation process. CONCLUSIONS: We demonstrated for the first time that the intraperitoneal administration of stem cells can guarantee a rapid liver engraftment. Moreover, the new protocol based on stem cell infusion following liver damage in the absence of irradiation may represent a step forward for the clinical application of stem cell transplantation.

Animals↗
PubMed2004

Stem cells in gynecology and obstetrics.

Over the past 10 years, we have become involved in a new research effort and an increasing scientific interest in the field of stem cell-based therapy. We are therefore able to describe different areas in which stem cell research can be applied and developed in gynecology and obstetrics. I) Hematopoietic stem cells have been used to set up therapeutic strategies for the treatment of gynecological solid tumors such as ovarian cancer. In this context different autologous or allogeneic transplantation approaches have been proposed and clinically investigated. II) Umbilical cord blood, which was often considered a waste material of the delivery, actually represents a precious source of stem cells that can be used for cell-based treatments of malignancies and inherited diseases. III) A feto-maternal cell traffic has recently been demonstrated through the placental barrier during pregnancy. This cellular exchange also includes stem cells from the fetus, which can generate microchimerisms in the mother and contribute to tissue repair mechanisms in different maternal organs. IV) Stem cells can be used for prenatal transplantation to treat different severe congenital diseases of the fetus. Nevertheless, several problems need to be solved to achieve an efficient in utero stem cell transplantation. Recent reports have pointed out the importance of timing in prenatal stem cell transplantation procedures and have shown the advantage of an early stem cell injection. An ultrasound-guided intracelomic approach could allow this possibility.

Antineoplastic Agents↗
PubMed2003

Efficacy of granulocyte transfusions for neutropenia-related infections: retrospective analysis of predictive factors.

BACKGROUND: The transfusion of G-CSf-primed granulocytes (GTX) might represent an important treatment option for neutropenia-related infections unresponsive to conventional antimicrobial therapies and to recombinant hematopoietic growth factors. However, few studies to date have identified the factors that can predict clinical outcome and the patient populations who are likely to benefit most from GTX. The primary endpoint of the present retrospective study was to evaluate the efficacy of GTX in 22 patients with hematological malignancies who developed neutropenia-related bacterial and fungal infections that were unresponsive to appropriate antimicrobial therapies. METHODS: Peripheral blood granulocytes were collected by continuous-flow leukapheresis from HLA-identical siblings after priming with G-CSF. The response to GTX was classified as 'favorable' if clinical symptoms and signs of infection resolved or 'unfavorable' if clinical symptoms and signs of infection were unchanged or worsened. Control of infection at Day 30 after the enrollment in the GTX program was considered as the outcome variable in multiple regression analysis. RESULTS: Two patients died of infection before receiving the granulocyte concentrates. Bacterial infections (monomicrobial or mixed bacteremias) were documented in 11 patients, whereas fungal infections (fungemia or focal fungal infections) were diagnosed in seven patients. In two patients, no infecting agent could be isolated (clinical infection). Control of infection at Day 30 after the first GTX was achieved in 10 of 20 assemble patients. Overall, 54% of patients with bacterial infections had a favorable response, compared with 57% of patients with fungal infections. No differences in terms of survival were found when comparing patients with bacterial and those with fungal infections at a median follow-up 90 days from the first GTX. In univariate analysis, disease status before GTX, e.g., complete or partial remission, and spontaneous recovery of the neutrophil count were significantly associated with control of infection. when multivariate regression models were formed, the recovery 0.5 x 10 (9)/L PMN was the only parameter that significantly and independently correlated with a favorable response to GTX. DISCUSSION: GTX can be used to successfully treat bacterial as well as fungal infections in severely neutropenic patients when administered early after the onset of febrile neutropenia in patients with remission of the underlying disease and who are likely to recover marrow function.

Adult↗
PubMed2002

Administration of low-dose interleukin-2 plus G-CSF/EPO early after autologous PBSC transplantation: effects on immune recovery and NK activity in a prospective study in women with breast and ovarian cancer.

This study evaluated the effects of low-dose IL-2 plus G-CSF/EPO on post-PBSC transplantation (PBSCT) immune-hematopoietic reconstitution and NK activity in patients with breast (BrCa) and ovarian cancer (OvCa). To this end, two consecutive series of patients were prospectively assigned to distinct post-PBSCT cytokine regimens (from day +1 to day +12) which consisted of G-CSF (5 microg/kg/day) plus EPO (150 IU/kg/every other day) in 17 patients (13 BrCa and 4 OvCa) or G-CSF/EPO plus IL-2 (2 x 10(5) IU/m(2)/day) in 15 patients (10 BrCa and 5 OvCa). Hematopoietic recovery and post-transplantation clinical courses were comparable in G-CSF/EPO- and in G-CSF/EPO plus IL-2-treated patients, without significant side-effects attributable to IL-2 administration. In the early and late post-transplant period a significantly higher PMN count was observed in G-CSF/EPO plus IL-2-treated patients (P = 0.034 and P = 0.040 on day +20 and +100, respectively). No significant differences were found between the two groups of patients in the kinetics of most lymphocyte subsets except naive CD45RA(+) T cells which had a delayed recovery in G-CSF/EPO plus IL-2 patients (P = 0.021 on day +100). No significant difference was observed between NK activity in the two different groups, albeit a significantly higher NK count was observed in G-CSF/EPO plus IL-2 series on day +20 (P = 0.020). These results demonstrate that low-dose IL-2 can be safely administered in combination with G-CSF/EPO early after PBSCT and that it exerts favorable effects on post-PBSCT myeloid reconstitution, but not on immune recovery.

Adult↗
PubMed2002

Transforming growth factor-beta1 transcriptionally activates CD34 and prevents induced differentiation of TF-1 cells in the absence of any cell-cycle effects.

A number of cytokines modulate self-renewal and differentiation of hematopoietic elements. Among these is transforming growth factor beta1 (TGF-beta1), which regulates cell cycle and differentiation of hematopoietic cells, but has pleiotropic activities depending on the state of responsiveness of the target cells. It has been previously shown by us and other authors that TGF-beta1 maintains human CD34(+) hematopoietic progenitors in an undifferentiated state, independently of any cell cycle effects, and that depletion of TGF-beta1 triggers differentiation accompanied by a decrease in CD34 antigen expression. In the present work, we show that exogenous TGF-beta1 upregulates the human CD34 antigen in the CD34(+) cell lines TF-1 and KG-1a, but not in the more differentiated CD34(-) cell lines HL-60 and K-562. We further studied this effect in the pluripotent erythroleukemia cell line TF-1. Here, TGF-beta1 did not effect cell growth, but induced transcriptional activation of full-length CD34 and prevented differentiation induced by differentiating agents. This effect was associated with nuclear translocation of Smad-2, activation of TAK-1, and with a dramatic decrease in p38 phosphorylation. In other systems TGF-beta1 has been shown to activate a TGF-beta-activated kinase 1 (TAK1), which in turn, activates p38. The specific inhibitor of p38 phosphorylation, SB202190, also increased CD34 RNA expression, indicating the existence of a link between p-38 inhibition by TGF-beta1 and CD34 overexpression. Our data demonstrate that TGF-beta1 transcriptionally activates CD34 and prevents differentiation of TF-1 cells by acting independently through the Smad, TAK1 and p38 pathways, and thus provide important clues for the understanding of hematopoietic development and a potential tool to modify response of hematopoietic cells to mitogens or differentiating agents.

Antigens, CD34↗
PubMed2001

Structural and functional mapping of the thrombin domain involved in the binding to the platelet glycoprotein Ib.

The activation of human platelets by alpha-thrombin is mediated in part by cleavage of the protease-activated receptor (PAR) 1 and 4 and by the glycoprotein (Ib)alpha, (Gp(Ib)alpha), which binds with high affinity to alpha-thrombin. Recent studies have shown that the thrombin domain referred to as heparin binding site (HBS) is involved in the interaction with the platelet Gp(Ib)alpha. The HBS is rich in basic amino acids. To identify the key amino acid residues involved in the binding to Gp(Ib)alpha, we have performed alanine scanning mutagenesis of the basic HBS R93, R97, R101, R233, K236, K240, R233/K236/Q239, as well as of the neutral Q239 residues, located in different regions of the domain. For comparison, mutation at R67 within the fibrinogen recognition site (FRS) of thrombin was performed as well. Solid-phase binding experiments showed that the Kd of thrombin-GpIb interaction was reduced 22-fold for R93A, 8-fold for R97A, 13-fold for R101A, 29-fold for R233A, 21-fold for K236A, 5-fold for K240A, and 31-fold for the triple mutant R233A/K236A/Q239A, while the Q239A and R67A forms did not show any significant affinity change. The platelet activating capacity of these mutants was evaluated as well. Using gel-filtered platelets, the EC50 value of thrombin-induced aggregation was from 5- to 13-fold higher in the HBS mutants than in the WT form, and was linearly and positively correlated with the corresponding Kd values pertaining to thrombin binding to GpIb. Measurements of PAR-1 hydrolysis on the platelet membrane showed that the HBS mutants R233A, R101A, R93A, K236A, and R233/K236/Q239 forms had a reduction of the apparent kcat/Km value. These results are a consequence of a defective binding to GpIb, which is known to optimize the interaction with PAR-1 in situ. A confirm of this hypothesis came from the demonstration that the kcat/Km value pertaining to the hydrolysis by the HBS-mutated thrombins of the synthetic PAR-1 38-60 peptide in solution was similar to that one obtained with the WT form. In conclusion, these experiments provide a structural and functional mapping of the thrombin HBS subregions involved in the binding to the platelet Gp(Ib)alpha and in the cell activation.

Acetylation↗
PubMed2001

HIV-protease inhibitors contribute to P-glycoprotein efflux function defect in peripheral blood lymphocytes from HIV-positive patients receiving HAART.

P-glycoprotein (P-gp) has been found expressed in normal human cells, such as bone marrow and peripheral blood cells. The aim of this study was to investigate whether HIV-protease inhibitors (HIV-PIs) interact with P-gp efflux function in normal human peripheral blood lymphocytes (PBLs) and CD34+ progenitor cells. Moreover, we analyzed the in vivo effect of HIV-PIs on P-gp function in PBLs from HIV-infected patients receiving highly active antiretroviral therapy (HAART). We found that HIV-PIs (i.e., ritonavir, saquinavir, nelfinavir and indinavir) interfere with P-gp function in normal PBLs as demonstrated by the reduced efflux of rhodamine 123 (Rh123). This effect was dose-dependent and suggested the following hierarchy: ritonavir > saquinavir > nelfinavir > indinavir. We further analyzed the effect of HIV-PIs on the P-gp function in specific PBLs subsets. Our results show an HIV-PI-induced inhibition of P-gp function in CD4+ and CD8+ T cell subsets, mostly caused by the effect on the naive compartment of both CD4+ and CD8+ T cells. The same inhibitory effect was found in CD34+ hematopoietic progenitor cells. With respect to the in vivo evaluation of P-gp function in PBLs from HIV-infected patients, we found reduced levels of Rh123 efflux that reached the lowest value in AIDS patients receiving HAART. We concluded that HIV-PIs interfere with P-gp function in major cellular targets for HIV infection, such as CD4+ T cells and CD34+ progenitor cells. This ability may contribute to P-gp efflux function defect found in HIV-infected patients and suggests that drug interaction studies are crucial to an overall understanding of the effects of this important group of drugs.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Expression of p15(ink4b) gene during megakaryocytic differentiation of normal and myelodysplastic hematopoietic progenitors.

In myelodysplastic syndrome (MDS), the expression of the cyclin-dependent kinase inhibitor p15(ink4B) (p15) is frequently decreased because of the aberrant methylation of the gene promoter; p15 is normally up-regulated during megakaryocytic differentiation. It was hypothesized that p15 methylation and deregulation of gene expression contribute to defective megakaryocytopoiesis in patients with MDS. Here it is shown that the increasing autocrine production of TGF-beta1 stimulates megakaryocytic differentiation in normal CD34(+) cells and that p15 mediates, at least in part, this effect. This TGF-beta1-dependent pathway is altered in MDS CD34(+) progenitors because of p15 methylation. The demethylating agent 2-deoxyAZAcytidin can restore the normal demethylated state of the p15 gene and increase its expression. Nevertheless, MDS CD34(+) cells only poorly differentiate to the megakaryocytic lineage. These findings suggest that p15 methylation occurs in a neoplastic clone with a profound defect of cell proliferation, survival, and differentiation that cannot be overcome by using a demethylating drug.

Anemia, Refractory, with Excess of Blasts↗
PubMed2001

Expression of the c-met proto-oncogene and its ligand, hepatocyte growth factor, in Hodgkin disease.

The receptor for hepatocyte growth factor (HGF) is a transmembrane tyrosine kinase that is encoded by the proto-oncogene c-met. Recently, c-MET was detected in Reed-Sternberg (RS) cells from Epstein-Barr virus-positive (EBV(+)) Hodgkin disease (HD). The c-MET, EBER-1, and LMP-1 expression in 45 lymph node biopsies and 12 bone marrow biopsies obtained from patients with HD was analyzed. In addition, HGF levels in serum samples from 80 healthy individuals and 135 HD patients in different phases of disease. In all 45 lymph node and 12 bone marrow samples examined, RS cells expressed c-MET but not HGF(+). These results were independent of the EBV infection. Interestingly, several HGF(+) dendritic-reticulum cells were found scattered around c-MET(+) RS cells. The mean +/- SEM serum HGF levels in HD patients at diagnosis and at the time of relapse were 1403 +/- 91 (95% confidence interval [CI], 1221-1585) and 1497 +/- 242 pg/mL (95% CI, 977-2017), respectively. HGF values were significantly higher than those of healthy individuals (665 +/- 28 pg/mL; 95% CI, 600-721; and P <.001 for both groups of patients) and of HD patients in remission (616 +/- 49 pg/mL; 95% CI, 517-714; and P <.001 for both groups of patients). A significant correlation was found between serum HGF levels and B symptoms at diagnosis (P =.014). In conclusion, this study indicates that HGF and c-MET constitute an additional signaling pathway between RS cells and the reactive cellular background, thereby affecting adhesion, proliferation, and survival of RS cells. Furthermore, the serum concentration of HGF in HD patients may be a useful tool in monitoring the status of disease.

Adolescent↗
PubMed2001

T-cell apoptosis induced by granulocyte colony-stimulating factor is associated with retinoblastoma protein phosphorylation and reduced expression of cyclin-dependent kinase inhibitors.

Peripheral blood progenitor cells (PBPC) mobilized by granulocyte colony-stimulating factor (G-CSF) promptly engraft allogeneic recipients after myeloablative chemotherapy for hematologic malignancies. Surprisingly, no exacerbation of acute graft-vs-host disease has been observed despite a 10-fold higher T-cell content in PBPC compared with bone marrow allografts. Because G-CSF can suppress T-cell proliferation in response to mitogens and enhance their activation-induced apoptosis, we examined the molecular mechanisms underlying G-CSF-induced immune dysfunction. Normal allogeneic lymphocytes were challenged with phytohemagglutinin in the presence of serum collected after G-CSF administration (postG) to healthy PBPC donors, and the expression of key components of the cell cycle and apoptotic machineries was investigated by flow cytometry and Western blotting. Lymphocyte stimulation was associated with collapse of mitochondrial transmembrane potential, hypergeneration of reactive oxygen intermediates, and activation of caspase-3 and DNA fragmentation. Lymphocytes were arrested in a G(1)-like phase of the cell cycle, as measured by G(1)-phase cyclin expression and bromodeoxyuridine (BrdUrd) incorporation. Cell tracking experiments confirmed the occurrence of a lower number of population doublings in postG compared with preG cultures. Unexpectedly, the phosphorylation state of the protein encoded by the retinoblastoma susceptibility gene (pRB) was unaltered in postG cultures, and the inhibition of cell cycle progression occurred without the recruitment of the cyclin-dependent kinase inhibitors p15(INK4B), p16(INK4A), and p27(Kip1). We eventually evaluated the ability of antioxidant/cytoprotectant agents to prevent the G-CSF-induced mitochondrial dysfunction and inhibition of cell cycle progression. Of interest, both N-acetylcysteine and amifostine reduced apoptotic cell death by 45% on average, inhibited the activation/processing of caspase-3, and increased BrdUrd incorporation in postG cultures. Based on these experimental findings, a model is proposed in which T-cell activation in the presence of serum immunoregulatory factor(s) induced by G-CSF is associated with a molecular phenotype mimicking the G(1)-S transition and consisting of pRB phosphorylation, lack of CDKI recruitment, and reduced cyclin-E expression. The putative relationship between lymphocyte mitogenic unresponsiveness and apoptosis induction would occur at the level of key molecules shared by the cell cycle and apoptotic machineries. Whether the G-CSF-mediated modulation of lymphocyte functions in vitro is beneficial in transplantation medicine remains to be determined.

Acetylcysteine↗