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Biomedical subjects

E Ottaviani

Publications and source records attributed to E Ottaviani.

At least 37 records · Page 2Linked to original sources

Morula cells as the major immunomodulatory hemocytes in ascidians: evidences from the colonial species Botryllus schlosseri.

Immunocytochemical methods were used to study the presence and distribution of IL-1-alpha- and TNF-alpha-like molecules in the hemocytes of the colonial ascidian Botryllus schlosseri. Only a few unstimulated hemocytes were positive to both the antibodies used. When the hemocytes were stimulated with either mannan or phorbol 12-mono-myristate, the phagocytes were not significantly changed in their number, staining intensity, or cell morphology. In contrast, stimulated morula cells were intensely labeled, indicating that these cells play an important immunomodulatory role.

Animals↗

Real-time quantification of different types of bcr-abl transcript in chronic myeloid leukemia.

BACKGROUND AND OBJECTIVES: The most common translocation in chronic myeloid leukemia (CML) t(9;22) (q34;q22) produces the BCR/ABL fusion gene. We set up and evaluated a rapid and reliable real-time reverse-transcription-polymerase chain reaction (RT-PCR) approach using TaqMan technology for detection and quantification of bcr-abl transcripts in CML patients at diagnosis and during therapy. DESIGN AND METHODS: A pair of primers and probe complementary to ABL exon 2 were designed, enabling detection of the most frequent bcr-abl transcripts, and also of the normal ABL-Ia transcript as an internal control. Conditions were established to amplify less than 1(-10) target molecules/reaction and detect one CML cell in 10(6) cells from healthy donors. To determine the utility of the assay, we quantified the bcr-abl/ABL-Ia ratio in 59 bone marrow samples (45 samples with evidence of different Ph+ chromosome percentages and 14 samples in complete cytogenetic remission) from 48 CML patients, 34 of them at diagnosis and 14 in clinical remission (CR). In 14 cases, this ratio was compared with results obtained by a competitive-quantitative RT-PCR/capillary electrophoresis method from contemporary specimens. RESULTS: By real-time RT-PCR, the median value of bcr-abl/ABL-Ia ratio at diagnosis was 15.334 (range 3.3-28.81) and fell to 0.9 (range 0.003-26.1) in CR. The median value of bcr-abl/ABL-Ia ratio at cytogenetic remission was 0.7 (range 0.003-2.83). The real-time bcr-abl/ABL-Ia ratios correlated with those obtained by competitive RT-PCR (p < 0.0001) and the percentage of Ph+ metaphases (p < 0.0001). The high sensitivity and specificity of the real-time RT-PCR procedure was confirmed in all 14 patients with minimal residual disease. INTERPRETATION AND CONCLUSIONS. We conclude that this real-time RT-PCR procedure is a reliable and sensitive method of monitoring CML patients after therapy, and that the bcr-abl/ABL-Ia ratio correlates strongly with cytogenetic analysis.

Bone Marrow↗

Molecular therapy for multiple myeloma.

BACKGROUND AND OBJECTIVES: Several molecular and cytogenetic advances have suggested novel therapeutic strategies that could help reach an eventual cure for multiple myeloma (MM). EVIDENCE AND INFORMATION SOURCES: Identification of novel, "MM-specific" molecular targets should pave the way for drugs that can specifically attack the neoplastic cells while sparing the normal ones. Drugs that alter the marrow microenvironment--such as bisphosphonates, proteasome inhibitors (e.g. PS-341/LDP341), lactacystin or LLNV compounds--induce apoptosis or G1 growth arrest and alter the adhesion of MM cells to marrow stroma. These drugs that modified microenvironment have a more solid scientific basis and may therefore have more realistic implications in MM treatment. Of these, novel vascular endothelial growth factor (VEGF) inhibitors, such as SU5416 and SU6668, block tumor-cell adhesion and could disrupt MM cell proliferation. Similar tyrosine kinase inhibitors (TKI) such as fibroblast growth factor receptor (FGFR) inhibitors may serve when the FGFR3 gene is overexpressed due to the t(4;14)(p16.3;q32) and/or is activated by point mutations. In cases carrying the translocation and expressing the IgH/WHSC1-MMSET hybrid transcripts, histone deacetylase (HDAC) inhibitors could be useful, but their possible clinical use need to be supported by more biological studies. Tumor necrosis factor alpha-related apoptosis-inducing ligand (TRAIL) induces apoptosis in MM cell lines and primary cells. The proliferative signaling pathway of FGFR3 is mediated by Ras (Ras-activating mutations are frequently found in MM), which presents a possible target for farnesyltransferase inhibitors (used alone or in association with IFN-alpha). PERSPECTIVES: In several of these options, preclinical studies have proved encouraging, and clinical trials are now getting underway.

Animals↗

Cytotoxicity and cytotoxic molecules in invertebrates.

Although lacking the components that characterize the acquired immunity systems of vertebrates, invertebrates nevertheless possess effective general innate immune mechanisms which exhibit striking parallels with those of vertebrates. These innate immune systems include both cellular and humoral elements. Invertebrate phagocytes synthesize both oxygen-dependent and oxygen-independent molecules to combat infectious agents. Cytotoxic substances employed by invertebrates include reactive intermediates of oxygen and nitrogen, antimicrobial peptides, lectins, cytokine- and complement-like molecules, and quinoid intermediates of melanin. The signal transduction pathways that are involved in mediating the production of these substances appear to be very similar among animal species, suggesting a common ancestral origin for the innate immune systems.

Animals↗

Neutral endopeptidase-24.11 (NEP) deactivates PDGF- and TGF-beta-induced cell shape changes in invertebrate immunocytes.

Using a cytofluorimetric assay, we found that immunocytes of the mollusc, Mytilus galloprovincialis, express CD10, a surface antigen known to be identical to neutral endopeptidase-24.11 (NEP). The spectrofluorimetric analysis demonstrates that the growth factors PDGF-AB and TGF-beta1 provoke an increase in NEP-like activity in membrane preparations from the immunocytes, but have no effect on the soluble form in the serum. On the other hand, computer-assisted microscopic image analysis reveals that NEP deactivates the PDGF-AB- and TGF-beta1-induced shape changes in immunocytes. However, Western blots show that, in solution, NEP does not cleave PDGF-AB or TGF-beta1, indicating that the inactivation is not due to proteolysis. These results suggest a functional interplay in invertebrate immunocytes between growth factors and NEP, as previously shown in vertebrate cells.

Animals↗

Immunomodulation by recombinant human interleukin-8 and its signal transduction pathways in invertebrate hemocytes.

We report the presence of interleukin (IL)-8-immunoreactive molecules in hemocytes from the mollusc Mytilus galloprovincialis. Functional studies demonstrate that recombinant human (rh)IL-8 provokes conformational changes, induces chemotaxis, and increases bacterial phagocytic activity in hemocytes. rhIL-8 induces cell shape changes via protein kinase A and C pathways. These morphological changes are followed by reorganization of the actin microfilaments. The findings suggest that, as previously reported for other cytokines, IL-8 is well conserved and deeply involved in immune functions from invertebrates to mammals.

Animals↗

PDGF and TGF-beta partially prevent 2-deoxy-D-ribose-induced apoptosis in the fat body cell line IPLB-LdFB from the insect Lymantria dispar.

The IPLB-LdFB cell line from the fat body of the insect Lymantria dispar shows the presence of immunoreactive, platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 molecules, as well as the corresponding plasma membrane-like receptors, i.e. PDGFR-alpha, PDGFR-beta and TGFR-beta type II. Cytofluorimetric and morphological studies reveal that the reducing sugar 2-deoxy-D-ribose (dRib), an apoptotic agent for human cells, induces apoptosis in a concentration- and time-dependent manner even in IPLB-LdFB cells. PDGF-AB and TGF-beta1 partially counteract the effect of dRib, indicating a survival role of these factors in this apoptotic model of insect cells.

Journal Article↗

Synergistic role of cAMP and IP(3) in corticotropin-releasing hormone-induced cell shape changes in invertebrate immunocytes.

Immunocytes from the mollusc Mytilus galloprovincialis express corticotropin-releasing hormone (CRH) receptor subtype (CRH-R1 and CRH-R2)-like mRNAs. Using computer-assisted microscopic image analysis, we have found that exogenous CRH provokes changes in the cellular shape of immunocytes, and that this response is extracellular Ca(2+)-dependent. The various inhibitors of transduction signaling pathways, i.e. suramin sodium, 2', 5'-dideoxyadenosine, neomycin sulfate, calphostin C, H-89, and wortmannin, completely or partially inhibit these changes. The present findings demonstrate that PKA, PKC, and PKB/Akt are involved in CRH-induced cell shape changes in immunocytes, and that the cellular effect of CRH needs the synergistic action of the two second messengers, cAMP and IP(3).

Animals↗

All-trans retinoic acid significantly reduces the incidence of early hemorrhagic death during induction therapy of acute promyelocytic leukemia.

Early hemorrhagic death (within the first 10 d of treatment [EHD]) is reported as the main cause of death during induction therapy for acute promyelocytic leukemia (APL). In order to evaluate possible differences in the incidence of EHD during induction regimens based on all-trans retinoic acid (ATRA), we retrospectively analyzed a consecutive series of 86 APL patients, diagnosed and treated at our Institution from 1982. Forty-three patients received combination chemotherapy with anthracyclines and cytosine arabinoside (January 1982 to December 1991), while induction of the remaining 43 was based on ATRA alone or on a combination of ATRA and anthracyclines (January 1992 to October 1996). There were significantly less induction deaths in the ATRA group [9 (chemotherapy group-CT) vs. 2 (ATRA group-RA) overall and 8(CT) vs. 1(RA) of EHD; p = 0.01]. Hemostatic evaluations showed an earlier reduction of D-dimer in the ATRA group. No cases of morphological resistance were observed in the ATRA group after induction. In addition, the number of relapses occurring in the first 24 months from the achievement of complete remission (CR) was significantly lower in the ATRA group (15 vs. 7; p = 0.01), with a disease free survival at 2 yr of 67% vs. 31%. In conclusion, ATRA appears to be able to significantly reduce the incidence of EHD, increasing the number of possible long-term remissions.

Antineoplastic Combined Chemotherapy Protocols↗

Quantification of BCR-ABL transcripts in CML patients in cytogenetic remission after interferon-alpha-based therapy.

We measured using a competitive quantitative polymerase chain reaction-capillary electrophoresis (PCR-CE)-based assay, the levels of bcr-abl transcripts in 44 patients with chronic myeloid leukemia (CML) after interferon-alpha (IFN-alpha) therapy, who achieved a major (10 patients, MCR group) or complete (34 patients, CCR group) cytogenetic response. All 34 CCR patients had molecular evidence of residual disease detected in bone marrow samples at the time of best karyotypic response. The median number of bcr-abl transcripts of 34 evaluable patients in the CCR group at the time of complete cytogenetic remission was 4/microg RNA (range 3-4600), while the median number of bcr-abl transcripts of 10 patients in the MCR group at the time of best cytogenetic response was 4490/microg RNA (range 600-23 900) (P = 0.000024). In nine CCR and five MCR patients we were able to quantify the amount of bcr-abl transcript both at diagnosis and after interferon therapy: no statistical difference (P = 0.18) was found between the two groups at diagnosis (median bcr-abl transcripts/microg RNA was 30 000 vs. 39 650, respectively). During IFN-alpha therapy, the two groups were evaluable at the time of major karyotypic conversion: at this point, there was a statistical difference of expression of bcr-abl transcript between the CCR group (17 patients) (median 2700; range 76-40 000) and the MCR group (10 patients) (median 4490; range 600-23 900), respectively (P = 0.046). No differences of bcr-abl amount of transcript were found in patients with CCR obtained either by IFN-alpha therapy alone (20 patients) vs. IFN-alpha plus ABMT (13 patients) (P = 0.47). We firstly demonstrated that although the CCR and MCR groups were clinically, cytogenetically and molecularly indistinguishable at diagnosis, the two groups could be recognized successfully during interferon therapy based on the level of bcr-abl transcript.

Adolescent↗

Human placenta, chorion, amnion and decidua express different variants of corticotropin-releasing factor receptor messenger RNA.

Human placenta is a major source of corticotropin-releasing factor (CRF), and local effects of CRF in fetal membranes and placenta have been shown, i.e., adrenocorticotropic hormone (ACTH) and oxytocin release from cultured placental cells, as well as prostaglandin release from amnion, chorion and decidua. Two distinct CRF receptors (CRF-R1 and CRF-R2) have been characterized: CRF-R1 consists of two isoforms (CRF-R1alpha and CRF-R1beta) while CRF-R2 has at least three different splice variants (CRF-R2alpha, CRF-R2beta and CRF-R2gamma). To date, CRF-R1 receptor has been identified in human placenta and in pregnant myometrium, while no evidence for placental CRF-R2 receptor isoforms has been provided. The present study investigated whether the different isoforms of CRF-R1 and CRF-R2 receptor mRNA are expressed in fetal membranes and placenta. Tissues were collected after spontaneous vaginal delivery (38-40 weeks) or elective caesarean section (39-41 weeks). The gene expression of CRF receptors was first studied by reverse transcriptase-polymerase chain reaction (RT-PCR), and the presence of CRF-R1alpha, but not of CRF-R1beta, in human placental trophoblast, amnion/chorion and decidua was shown. In addition, among the three CRF-R2 splice variants, only CRF-R2beta mRNA was expressed by trophoblast and fetal membranes. By using in situ hybridization, CRF-R1 and CRF-R2 probes positively hybridized trophoblast and related membranes. CRF-R1 was localized in the syncytiotrophoblast cells, chorionic trophoblast and decidua with a small amount in the amnion. CRF-R2 probe mainly hybridized syncytiotrophoblast cells, but cytotrophoblast also contained discreet amounts of CRF-R2 mRNA signal. The CRF-R2 hybridization signal was also observed within the structure of the villi (blood vessels), chorionic trophoblast and decidual cells, but it was faint or absent in the amniotic epithelium. There was no significant difference in the distribution of CRF-R1 or CRF-R2 mRNA signal between placentas collected from vaginal delivery or caesarean section. The evidence that intrauterine tissues differently express CRF-R1alpha and CRF-R2beta supports possible different local roles of CRF and related peptides into intrauterine tissues during pregnancy.

Amnion↗

Repair of molluscan tissue injury: role of PDGF and TGF-beta1.

Various cellular and humoral activities of the wound repair process and the effects of PDGF-AB and TGF-beta1 on tissue repair mechanisms in the mollusc Limax maximus are studied by histological and immunocytochemical procedures. Histological examination at different times after the wound production demonstrates that tissue repair is the result of successive and related activities distinguishable by different morphological pictures. In the first hours, an infiltration phase is activated 24 h after the incision, hemocytes stratify at wound margins and actively phagocitize cell debris and damaged tissue in the surrounding area. Moreover, the cells are immunoreactive to anti-IL-1alpha, IL-8 and TNF-alpha antibodies. After 24-72 h, granulation tissue rich in small blood lacunae is formed and the provisional matrix is synthesized and deposited on the base of the new tissue. In histological sections 72 h after injury, the incision is filled with granulation tissue, and at the wound base, a layer of fibrous connective tissue is formed. Hemocytes present in the newly formed blood lacunae and fibroblasts are involved in the synthesis and deposit of extracellular matrix components, i.e. fibronectin, reticular and collagen fibres. Ninety-six h after wound production, the repair process continues and the granulation tissue is more developed. At 192 h, re-epithelialization begins, and this is more evident in the histological sections after 14 days. Hemocytes are immunoreactive to the cytokines at all the times examined. Exogenous administration of PDGF-AB and TGF-beta1 stimulates the tissue healing process through a general acceleration of the activities involved. A larger closing area of clumped hemocytes and a smaller damaged tissue area are observed 24 h after treatment of the wound. At 72 h, the granulation tissue is more developed and more extracellular matrix components are deposited than in the control incision. A larger number of cells express cytokine-like molecules, and re-epithelialization of the wound is accelerated, as 14 days after growth factor treatments almost all the wound area is covered by a layer of cubic epithelial cells, and the alcianophilic cell coat is restored. No differences in the responses of the two growth factors are observed.

Animals↗

Fibroblast responses to exogenous and autocrine growth factors relevant to tissue repair. The effect of aging.

The aging process is often associated with impaired wound healing, but the cellular and molecular mechanisms implicated are not completely understood. Accordingly, we have investigated the response of human fibroblasts from donors of various ages to platelet-derived and autocrine growth factors, in terms of mitogenicity as well as extracellular matrix synthesis and degradation. Our data indicate that fibroblast responses persist during aging, suggesting the involvement of systemic factors in the regulation of the healing process. In this context, we have found that neutral endopeptidase-24.11, a metalloproteinase controlling the action of neuroendocrine peptides and also of immunocyte chemotaxis, is overexpressed during aging. Finally, the connection between these data and those from in vitro aging studies is discussed.

Adult↗

Inflamm-aging. An evolutionary perspective on immunosenescence.

In this paper we extend the "network theory of aging," and we argue that a global reduction in the capacity to cope with a variety of stressors and a concomitant progressive increase in proinflammatory status are major characteristics of the aging process. This phenomenon, which we will refer to as "inflamm-aging," is provoked by a continuous antigenic load and stress. On the basis of evolutionary studies, we also argue that the immune and the stress responses are equivalent and that antigens are nothing other than particular types of stressors. We also propose to return macrophage to its rightful place as central actor not only in the inflammatory response and immunity, but also in the stress response. The rate of reaching the threshold of proinflammatory status over which diseases/disabilities ensue and the individual capacity to cope with and adapt to stressors are assumed to be complex traits with a genetic component. Finally, we argue that the persistence of inflammatory stimuli over time represents the biologic background (first hit) favoring the susceptibility to age-related diseases/disabilities. A second hit (absence of robust gene variants and/or presence of frail gene variants) is likely necessary to develop overt organ-specific age-related diseases having an inflammatory pathogenesis, such as atherosclerosis, Alzheimer's disease, osteoporosis, and diabetes. Following this perspective, several paradoxes of healthy centenarians (increase of plasma levels of inflammatory cytokines, acute phase proteins, and coagulation factors) are illustrated and explained. In conclusion, the beneficial effects of inflammation devoted to the neutralization of dangerous/harmful agents early in life and in adulthood become detrimental late in life in a period largely not foreseen by evolution, according to the antagonistic pleiotropy theory of aging.

Aging↗

Molecular remission after allogeneic or autologous transplantation of hematopoietic stem cells for multiple myeloma.

PURPOSE: To assess the clinical relevance of minimal residual disease (MRD) in patients with multiple myeloma (MM), 50 patients were monitored while they were in complete clinical remission (CCR) after autologous or allogeneic stem-cell transplantation. PATIENTS AND METHODS: Stringent molecular monitoring using clonal markers based on rearranged immunoglobulin heavy-chain genes was performed in 44 of 50 MM patients in CCR. Molecular clinical remission (MCR) was defined as more than one consecutive negative polymerase chain reaction (PCR) test result. RESULTS: Twelve (27%) of 44 molecularly monitored patients achieved MCR; four of the 12 became PCR-positive, and one of these four relapsed. In comparison with patients who did not achieve MCR, patients who achieved MCR had a significantly lower relapse rate (41% v 16%; P <.05) and longer relapse-free survival (35 v 110 months; P <.005). Fourteen of 26 patients in CCR who had received allografts were evaluated on a molecular basis: seven (50%) of the 14 achieved MCR and did not relapse; one of the seven remaining patients relapsed. Thirty of 47 patients in CCR who received autografts were evaluated on a molecular basis: five (16%) of the 30 achieved MCR; two of these five became PCR-negative, and one of these two relapsed. Ten of the 25 remaining patients later relapsed. For these nonrandomized groups, the higher MCR rate after allograft procedures was statistically significant (P <.01; Fisher's exact test). CONCLUSION: MCR can be obtained in a relatively high proportion of MM patients who have achieved CCR after undergoing allograft procedures and in a smaller fraction of patients after undergoing autograft procedures. In approximately one fourth of MM patients who achieve CCR after transplantation, it may be possible to keep the disease burden constantly below the PCR threshold. Because MCR was associated with prolonged relapse-free survival, these patients could have a relatively favorable clinical outcome.

Adult↗

Quantitative evaluation of BCR-ABL amount of transcript post mobilization with G-CSF of peripheral blood stem cells from chronic myeloid leukemia patients in cytogenetic response.

We studied nine patients affected by chronic myeloid leukemia (CML Ph+ and bcr-abl positive) and treated with alpha-interferon (alpha-INF) in order to: first, to evaluate the feasibility of a mobilization of peripheral blood stem cells induced by granulocyte-colony-stimulating factor (G-CSF) and the contamination by Ph+ cells and second, to quantify the amount of bcr-abl leukemia associated transcript by a quantitative assay during mobilization procedures, and post mobilization follow-up. Eight achieved a complete karyotypic remission before mobilization obtained with discontinuation of alpha-INF for few days and G-CSF at a dosage of 15 microg/kg/day for 5-7 consecutive days. By quantitative-competitive polymerase chain reaction (QC-PCR) assay, all the leukaphereses and bone marrow samples during post mobilization follow up were studied to determine the amount of bcr-abl transcript. Karyotypic and molecular analysis on evaluable leukapheresis showed that all the harvests were Ph negative and bcr-abl positive: in seven cases the levels of bcr-abl transcript were higher or equal to the pre-apheresis status. In three out of four patients, who underwent more than one leukapheresis procedure, we noticed a decreasing amount of bcr-abl contamination from the first to the last apheresis. Our results suggest that in patients who achieved a complete or major cytogenetic conversion with alpha-INF, it is possible to obtain a sufficient amount of PBSC for autografting by leukapheresis following priming G-CSF therapy and that the amount of neoplastic transcript does not seem to increase.

Adolescent↗

Alu and translisin recognition site sequences flanking translocation sites in a novel type of chimeric bcr-abl transcript suggest a possible general mechanism for bcr-abl breakpoints.

BACKGROUND AND OBJECTIVE: We further characterized a novel type of chimeric BCR-ABL mRNA transcript detected in a patient with Philadelphia chromosome positive (Ph+) chronic myeloid leukemia (CML). DESIGN AND METHODS: We used reverse-transcription polymerase chain reaction (RT-PCR) and sequence analysis of the fusion region of the amplified cDNA fragment. Western analysis was performed on total protein. RESULTS: Part of exon e8 of the BCR gene was joined to an intronic sequence of ABL intron Ib spliced on exon a2 of the ABL gene, giving rise to an in-frame e8-int-a2 BCR-ABL transcript. Only part of exon 8 of the BCR gene (e8) (intra-exonic break) was retained. The consequent BCR-int-ABL transcript was translated into a BCR-ABL protein of 1804 amino acid residues with a molecular mass of 197.5 kilodaltons (kDa) called p200 BCR-ABL. The 3' part of bcr exon 8 recombined within or alongside Alu elements at the additional sites. Sequence motifs similar to consensus binding sites of the lymphoid-associated TRAX and translisin proteins were present on both participating strands at 22q11 and 9q34 recombination sites, respectively. No differences in clinical or laboratory findings at diagnosis were found between this patient and CML patients with bcr-abl fusion. INTERPRETATION AND CONCLUSIONS: The presence of Alu sequences and of the translisin binding motif on both sides of the breaks in this novel translocation suggests a possible general mechanism of molecular recombination in CML patients.

Alu Elements↗