Sub-Nyquist field trial using time frequency packed DP-QPSK super-channel within fixed ITU-T grid.

Sub-Nyquist time frequency packing technique was demonstrated for the first time in a super-channel field trial transmission over long-haul distances. The technique allows a limited spectral occupancy even with low order modulation formats. The transmission was successfully performed on a deployed Australian link between Sydney and Melbourne which included 995 km of uncompensated SMF with coexistent traffic. 40 and 100 Gb/s co-propagating channels were transmitted together with the super-channel in a 50 GHz ITU-T grid without additional penalty. The super-channel consisted of eight sub-channels with low-level modulation format, i.e. DP-QPSK, guaranteeing better OSNR robustness and reduced complexity with respect to higher order formats. At the receiver side, coherent detection was used together with iterative maximum-a-posteriori (MAP) detection and decoding. A 975 Gb/s DP-QPSK super-channel was successfully transmitted between Sydney and Melbourne within four 50GHz WSS channels (200 GHz). A maximum potential SE of 5.58 bit/s/Hz was achieved with an OSNR = 15.8 dB, comparable to the OSNR of the installed 100 Gb/s channels. The system reliability was proven through long term measurements. In addition, by closing the link in a loop back configuration, a potential SE∙d product of 9254 bit/s/Hz·km was achieved.

Promyelocytic leukemia-specific PML-retinoic acid alpha receptor fusion protein interferes with erythroid differentiation of human erythroleukemia K562 cells.

Acute promyelocytic leukemia (APL) is characterized by a t(15;17) chromosomal translocation with breakpoints within the retinoic acid alpha receptor (RAR alpha) gene on 17 and the PML gene, which encodes a putative transcription factor, on 15. A PML-RAR alpha fusion protein is formed as a consequence of the translocation. We show here that expression of the PML-RAR alpha protein in K562 erythroleukemia cells results in a reduced expression of erythroid differentiation markers and a reduced sensitivity to the erythroid differentiative action of heme. Overexpression of RAR alpha, but not of PML, elicited a similar inhibition of K562 erythroid differentiation. These findings indicate that overexpression of either RAR alpha or PML/RAR alpha interferes with erythroid differentiation and support the hypothesis that RAR alpha is involved in the regulation of normal hematopoiesis and alteration of the RAR alpha signaling by PML/RAR alpha is implicated in the promyelocytic leukemogenesis.

PML/RAR alpha+ U937 mutant and NB4 cell lines: retinoic acid restores the monocytic differentiation response to vitamin D3.

We have analyzed the differentiation program of a U937 promonocytic leukemia clone transduced with the acute promyelocytic leukemia specific PML/RAR alpha fusion gene, the expression of which is under the control of the inducible metallothionine (MT) I promoter (MTPR9 clone). MTPR9 cells treated with Zn2+ hence exhibit levels of PML-RAR alpha protein as high as fresh acute promyelocytic leukemia blasts. In the absence of Zn2+, i.e., upon low level PML/RAR alpha expression, 1,25-dihydroxyvitamin D3 (D3) and particularly D3 plus transforming growth factor beta 1 (TGF-beta 1) induced terminal differentiation of MTPR9 cells (as observed in "wild-type" U937 cells), on the basis of morphology, membrane antigen pattern, and functional criteria. Conversely, in the presence of Zn2+, D3 and D3 plus TGF-beta 1 failed to induce terminal differentiation, as evaluated by the above parameters. Interestingly, retinoic acid (RA) treatment suppresses the differentiation blockade induced by high level PML-RAR alpha protein; indeed, Zn(2+)-treated MTPR9 cells incubated with RA plus D3 exhibited significant terminal monocytic maturation, comparable to that of cells treated with D3 alone or combined with RA in absence of Zn2+. Similar observations were made in NB4, a PML-RAR+ human acute leukemic line. As expected RA treatment of NB4 cells causes granulocytic differentiation. Interestingly, the cell line is only scarcely induced to mature monocytic cells by D3 or D3 plus TGF-beta 1 treatment, whereas it is effectively induced to monocytic maturation by combined treatment with D3 and RA. Accordingly, the rate of NB4 cell proliferation is only slightly affected by D3 or D3 plus TGF-beta 1 treatment, mildly inhibited by RA, and markedly decreased by D3 plus RA. These results indicate that in both U937 and NB4 cells high level PML/RAR alpha expression inhibits the monocytic terminal differentiation program triggered by D3 or D3 plus TGF-beta 1, whereas RA treatment effectively antagonizes this inhibitory PML-RAR alpha action and restores the D3 differentiative effect.

Adoptive immunotherapy of human cancer: the cytokine cascade and monocyte activation following high-dose interleukin 2 bolus treatment.

Serum concentration kinetics of gamma-interferon (IFN-gamma), neopterin, 2'-5' A synthetase and tumor necrosis factor alpha were determined in five cancer patients undergoing adoptive immunotherapy with high-dose interleukin 2 (IL-2) bolus infusion and lymphokine-activated killer cells according to the National Cancer Institute, NIH protocol. In all cases a significant increase of these markers was observed after IL-2 treatment. This suggests that the antitumor effect of high-dose IL-2 bolus administration may be in part mediated by activation of a cascade of endogenous cytokines including IFN-gamma and tumor necrosis factor alpha. After IL-2 bolus injection, the kinetics of neopterin was similar but delayed when compared to that of IFN-gamma: this suggests that macrophages, the specific source of neopterin, become activated by IFN-gamma following IL-2-mediated lymphocyte induction, thus implying a possible role for macrophages in the antitumor effects mediated by IL-2 and lymphokine-activated killer cells.

Terminal megakaryocytic differentiation of TF-1 cells is induced by phorbol esters and thrombopoietin and is blocked by expression of PML/RARalpha fusion protein.

We have analyzed the differentiation program of growth factor-dependent TF-1 erythroleukemia cells as well as clones with inducible expression of the APL-specific PML/RARalpha protein. We have shown that TF-1 cells may be induced to megakaryocytic differentiation by phorbol ester (phorbol dibutyrate, PDB) addition, particularly when combined with thrombopoietin (Tpo). RT-PCR studies showed that Tpo induces Tpo receptor (TpoR or c-mpl), whose expression was further potentiated by PDB addition. When the cells are induced with both PDB and Tpo erythropoietin receptor (EpoR) expression was inhibited. In the absence of Zn2+-induced PML/RARalpha expression, PDB and Tpo induced megakaryocytic differentiation of TF-1 MTPR clones as observed in 'wild-type' TF-1 cells. Conversely, when PML/RARalpha expression was induced by Zn2+, PDB and Tpo treatment of these clones caused only a reduced level of megakaryocytic differentiation. These observations indicate that: (1) TF-1 cells as well as other erythroleukemic cells, possess the capacity to differentiate to megakaryocytic cells when grown in the presence of protein kinase (PKC) activators and more efficiently when combined with Tpo; (2) the PML/RARalpha gene has a wide capacity to interfere with the program of hematopoietic differentiation, including megakaryocytic differentiation. Finally, we also observed that PML/RARalpha expression in TF-1 cells induces an up-modulation of interleukin-3 receptor, c-kit and c-mpl, a phenomenon which may offer these cells a growth advantage.

Interleukin-2 bolus therapy induces immediate and selective disappearance from peripheral blood of all lymphocyte subpopulations displaying natural killer activity: role of cell adhesion to endothelium.

As early as 10-15 min after the start of a 30 min interleukin-2 (IL-2) infusion, a rapid, virtually complete disappearance of all natural killer (NK) lymphocyte subpopulations (including both CD3- CD56+ and CD3+ CD56+ cells with either alpha/beta or gamma/delta T-cell receptor) was observed from peripheral blood. In contrast, the number of T lymphocytes (CD3+ CD56-) was unmodified for at least 2 h after IL-2 injection. The IL-2-induced, rapid disappearance from peripheral blood of NK and NK-like lymphocytes may be related to their massive adherence to the activated endothelium. In this regard, IL-2 infusion caused a very rapid rise of tumour necrosis factor-alpha (TNF-alpha) plasma concentration, whereas other cytokines, such as interferon-gamma (IFN-gamma), were induced only at later times. In vitro experiments indicated that IL-2, either alone or better combined with TNF-alpha, exerts a rapid and selective stimulatory effect on NK adhesion to endothelial cells. On the basis of these findings, we suggest that the activation of NK lymphocytes induced by IL-2, alone or combined with TNF-alpha, plays a key role in mediating the massive and selective adherence of NK and NK-like cells following IL-2 bolus infusion.

Primary hypothyroidism associated with interleukin-2 and interferon alpha-2 therapy of melanoma and renal carcinoma.

Four patients out of twenty with renal cancer and melanoma undergoing cancer immunotherapy with interleukin 2 (IL-2) and interferon alpha-2 (IFN-alpha 2) had laboratory evidence of hypothyroidism starting at cycle three to six, with a decline in serum thyroxine below normal and, in three cases, a rise in serum thyrotropin and thyroglobulin. One hypothyroid patient had elevated serum antimicrosomal antibody titres before the start of treatment and two others responded similarly during therapy. Three of the sixteen euthyroid patients also developed elevated titres of this antibody. Partial or complete remission was observed in seven of the patients--three of the four with hypothyroidism showed tumour regression. Thus IL-2 and IFN-alpha 2 can cause hypothyroidism, presumably via induction or exacerbation of autoimmune thyroid reactions. The occurrence of hypothyroidism may be mediated by high-dose IL-2 (rather than by LAK cell therapy as previously suggested) and potentiated by IFN-alpha 2.

Fluctuations of plasma beta 2-microglobulin, soluble interleukin 2 receptor and interferon-gamma concentrations after adoptive immunotherapy with high-dose interleukin 2 and lymphokine-activated killer cells.

We report the serum levels of soluble interleukin 2 receptor (sIL2R), beta 2-microglobulin (beta 2-M) and interferon-gamma (IFN-gamma) in patients undergoing adoptive immunotherapy with rIL2 and lymphocyte-activated killer (LAK) cells. Our results indicate that rIL2 induced a marked increase of the serum concentration of these markers, although this increase varied considerably for different individuals. Parallel studies with the same patients also showed a marked rise in the number of IL2R+ lymphocytes: the IL2Rs expressed on these cells were mainly of the "low affinity" type. We suggest that evaluation of these markers may allow the monitoring of immune system activation induced by rIL2 in patients undergoing adoptive rIL2 and LAK cell immunotherapy.

Long-term culture growth of CD4-CD8- lymphocytes exhibiting elevated non-MHC-restricted cytotoxic activity.

We have developed a culture system for "long-term" growth of human lymphokine-activated killer (LAK) cells exhibiting an elevated, wide-spectrum anti-tumor cytotoxicity. The system allows the exponential growth of monocyte- and B-lymphocyte-depleted CD4-CD8- lymphocytes in the presence of human AB serum and recombinant human interleukin-2 (IL-2) (2 x 10(2) U/ml) combined with interleukin (IL-1) beta (50 ng/ml). After 21 days in culture, these cells undergo massive amplification (i.e., the cell yield rises up to 30-120 times the starting values), and exhibit a marked anti-tumor cytotoxic activity against a panel of natural killer (NK)-resistant tumor cell lines. Interestingly, this activity correlates with the high level of perforin RNA. The membrane phenotypes of the final cell population, assessed by a panel of monoclonal antibodies (MoAbs) indicate a mixed population comprising two cell types in variable proportions (i) NKH-1+, T cell receptor (TCR) alpha/beta-, TCR gamma/delta-, CD3-, Leu 23+; (ii) NKH-(+), TCR alpha/beta-, TCR gamma/delta+, CD3+, Leu 23+. This culture system may provide a tool for cellular and molecular studies on the mechanisms of anti-tumor cytotoxicity, as well as the basis for new adoptive immunotherapy protocols in advanced cancers.

The synergistic effect of simultaneous addition of retinoic acid and vitamin D3 on the in-vitro differentiation of human promyelocytic leukemia cell lines could be efficiently transposed in vivo.

Both human cell lines HL-60 and AML-193 exhibit a myeloblastic and promyelocytic morphology, respectively, but may be regarded as bipotent leukemic precursors. They can be triggered to differentiate to either granulocytes or monocytes upon retinoic acid (RA) or 1,25-dihydroxyvitamin D (D3) addition, respectively. We have investigated the effect of combined addition of these chemical inducers on the in-vitro differentiation of both cell lines. RA and D3 added together exert synergistic effects on the in-vitro maturation of these myeloid cell lines. Interestingly, the additive effects were lost if the cells were incubated with the inducers added at sequential times. The synergistic effect could be transposed in vivo and could be clinically significant in the treatment of the promyelocytic leukemia. This clinical strategy may help to prevent retinoic acid resistance or to overcome it in patients relapsed after RA therapy and usually unresponsive to a reinduction therapy with RA alone.

Interleukin 2 in cancer therapy.

The goal of adoptive immunotherapy is the stimulation of host antitumor immunity, either cellular or humoral. The introduction of recombinant human cytokines into clinical oncology represents a new useful tool for the development of new strategies of antitumor immunotherapy. This article describes the current clinical status of IL-2 in the therapy of human cancer as it relates to what is already known about the biology and activity of this lymphokine. All the evidences suggest that the antitumor effect of IL-2 seems to be mediated through complex indirect mechanisms involving different effector cells of the immune system.

Design, recruitment, logistics, and data management of the GEHA (Genetics of Healthy Ageing) project.

In 2004, the integrated European project GEHA (Genetics of Healthy Ageing) was initiated with the aim of identifying genes involved in healthy ageing and longevity. The first step in the project was the recruitment of more than 2500 pairs of siblings aged 90 years or more together with one younger control person from 15 areas in 11 European countries through a coordinated and standardised effort. A biological sample, preferably a blood sample, was collected from each participant, and basic physical and cognitive measures were obtained together with information about health, life style, and family composition. From 2004 to 2008 a total of 2535 families comprising 5319 nonagenarian siblings were identified and included in the project. In addition, 2548 younger control persons aged 50-75 years were recruited. A total of 2249 complete trios with blood samples from at least two old siblings and the younger control were formed and are available for genetic analyses (e.g. linkage studies and genome-wide association studies). Mortality follow-up improves the possibility of identifying families with the most extreme longevity phenotypes. With a mean follow-up time of 3.7 years the number of families with all participating siblings aged 95 years or more has increased by a factor of 5 to 750 families compared to when interviews were conducted. Thus, the GEHA project represents a unique source in the search for genes related to healthy ageing and longevity.

High dose-intense chemotherapy alone or in combination with interleukin-2 for small cell lung cancer: a pilot study.

Given the antitumor activity of interleukin-2 (IL-2) against some drug-resistant cancer cells, 17 previously untreated patients with small cell lung cancer entered a pilot study to evaluate the feasibility, efficacy, and immunological effects of combining 12-week high dose-intense chemotherapy based on a modified Evans regimen (CAV/PE) with different IL-2 schedules (6-12 MU/m2 week as a 48-72-h infusion using the same cumulative dose, 72 MU/m2). Despite significant myelotoxicity, up to 70% of the intended dose intensity was delivered, showing no differences with regard to the IL-2 schedule used. Immunotherapy-induced toxicity was usually mild and manageable. No limiting effects were observed in patients receiving immunotherapy except for a very poor compliance to the 12-week IL-2 regimen. The low-dose 72-h infusion was the optimal IL-2 schedule. As given in this study, neither of the alternating CAV/PE regimens abrogated the effects of IL-2 on T-cell and NK-cell subsets, showing typical kinetics with rebound in lymphocytes following each discontinuation of the IL-2. While immunological changes cannot predict the antitumor effect of IL-2, they are consistent with those described for IL-2 alone, suggesting its compatibility with high dose-intense chemotherapy. Although no definite advantages have been demonstrated in this small pilot study with significant unbalanced prognostic factors (12% 2-year survival), both the preserved immunostimulatory effects and the lack of limiting overlapping toxicity make this combined approach promising and worthy of further clinical investigation.

Combined vitamin D3/retinoic acid induction of human promyelocytic cell lines: enhanced phagocytic cell maturation and hybrid granulomonocytic phenotype.

Studies on the effect of retinoic acid (RA) and 1,25-dihydroxyvitamin (D3) on the differentiation of leukemic cells have provided insight into the cellular and molecular mechanisms underlying hematopoietic cell differentiation. We have evaluated the combined effect of these chemical inducers on the differentiation of HL-60 and AML-193 promyelocytic leukemia cell lines. Simultaneous RA+D3 addition potentiated leukemic cell maturation up to mature phagocytic cells. Interestingly, AML-193 cells induced with D3 and RA displayed a typical neutrophilic morphology while exhibiting properties specific to monocytic cells, e.g., high expression of CD14 membrane antigen, capacity to bind bacterial lipopolysaccharide, and monocytic-specific esterase activity; this hybrid granulomonocytic (GM) phenotype was not observed upon initial incubation with one inducer and later addition of the other. Parallel control studies were performed with purified normal GM progenitors, triggered by interleukin 3+GM-colony-stimulating factor (CSF) in FCS-rich or -free clonogenic culture, by GM-CSF+M-CSF in FCS-rich clonogenic culture, and by M-CSF in liquid suspension culture. The progenitors grown in the first condition generate exclusively G clones, even upon addition of D3 and/or RA. The progenitors grown in the second and third culture conditions generate either G and M clones (second culture condition) or a population of cells composed by a majority of monocytes (third culture condition); the D3 addition did not modify this differentiation pattern, whereas RA or RA+D3 addition elicited a marked inhibition of monocytic differentiation. These observations suggest that the development of a hybrid GM phenotype is restricted to the progeny of bipotent GM leukemic precursors.

Transforming growth factor-beta potentiates vitamin D3-induced terminal monocytic differentiation of human leukemic cell lines.

We have investigated the effects of 1,25-dihydroxyvitamin D3 (D3) and/or transforming growth factor (TGF)-beta on one monocytic (U-937) and two human promyelocytic (HL-60 and AML-193) leukemic cell lines. D3 addition induces a partial monocytic maturation of the cell lines, whereas TGF-beta treatment is largely ineffective. Combined treatment with TGF-beta and D3 causes terminal monocytic maturation, as evaluated both by assessment of a large spectrum of membrane Ag and by functional assays. Furthermore, sequential addition of the two inducers showed that pretreatment with TGF-beta 1 followed by incubation with D3, but not vice versa, induces monocytic maturation as effectively as simultaneous treatment with both agents. In liquid culture the proliferative activity of these cell lines is slightly decreased by D3 and virtually unaffected by TGF-beta, whereas combined treatment with D3 and TGF-beta induces a markedly potentiated inhibitory effect. Furthermore, TGF-beta/D3 treatment (but not D3 alone) elicits the expression of membrane CD14, FcRI, FcRII, CD11a, CD11b, CD11c, ICAM-1, and PECAM-1 Ag at a level comparable to that observed on normal human monocytes. It is noteworthy that several of these Ag play an important role in monocyte physiology (e.g., CD14 Ag mediates the binding of bacterial LPS to monocytes). Treatment with both TGF-beta and D3 (but not D3 alone) induces superoxide anions and H2O2 production similar to that of circulating monocytes. In semisolid culture, D3 and TGF-beta alone cause, respectively, a marked and slight loss of cloning efficiency of the cell lines, whereas their combined addition synergistically results in a complete loss of the cloning capacity. These findings suggest a physiologic role for TGF-beta in monocyte maturation. Furthermore, they may pave the way to the design of clinical protocols combining D3 and TGF-beta in the differentiation therapy of acute promyelocytic/myelomonocytic leukemia.

Interleukin-2-dependent long-term cultures of low-density lymphocytes allow the proliferation of lymphokine-activated killer cells with natural killer, Ti gamma/delta or TNK phenotype.

We have developed a culture system for "long-term" growth of human lymphokine-activated killer (LAK) cells exhibiting an elevated, wide-spectrum antitumor cytotoxicity. The system allows the exponential growth of monocyte-depleted low-density lymphocytes in the presence of human serum and recombinant human interleukin-2 (10(3) U/ml), alone or in combination with interleukin-1 alpha or beta (both at 10 U/ml). Eighteen cultures were established from 18 normal adult donors. The membrane phenotypes of the final LAK cell population, assessed by a panel of monoclonal antibodies (mAb), consist of three main types: (a) NKH-1+, Ti alpha/beta-, Ti gamma/delta-, and CD3- lymphocytes; (b) NKH-1+, Ti alpha/beta-, Ti gamma/delta+, and CD3+ lymphocytes and (c) NKH-1+, Ti alpha/beta+, Ti gamma/delta- and CD3+ lymphocytes. Northern blot analysis showed that all these cell populations express relatively high levels of perforin RNA, particularly cells exhibiting the first phenotype. This culture system may provide a tool for cellular and molecular studies on the mechanisms of antitumor cytotoxicity, as well as the basis for new adoptive immunotherapy protocols in advanced center.

Expression of growth factor receptors in unilineage differentiation culture of purified hematopoietic progenitors.

We have evaluated the expression of growth factor receptors (GFRs) on early hematopoietic progenitor cells (HPCs) purified from human adult peripheral blood and induced in liquid suspension culture to unilineage differentiation/maturation through the erythroid (E), granulocytic (G), megakaryocytic (Mk), or monocytic (Mo) lineage. The receptors for basic fibroblast GF (bFGF), erythropoietin (Epo), thrombopoietin (Tpo), and macrophage colony-stimulating factor (MCSF) have been only assayed at mRNA level; the majority of GFRs have been evaluated by both mRNA and protein analyses: the expression patterns were consistent at both levels. In quiescent HPCs the receptors for early-acting [flt3 ligand (FL), c-kit ligand (KL), bFGF, interleukin-6 (IL-6)] and multilineage [IL-3, granulocyte-macrophage CSF (GM-CSF)] HGFs are expressed at significant levels but with different patterns, eg, kit and flt3 are detected on a majority and minority of HPCs, respectively, whereas IL-3Rs and GM-CSFRs are present on almost all HPCs. In the four differentiation pathways, expression of early-acting receptors shows a progressive decrease, more rapidly for bFGFR-1 and flt3 than for c-kit; furthermore, c-kit is more slowly downmodulated in the E and Mk than the G and Mo lineages. As a partial exception, IL-6Rs are still detected through the early or late stages of maturation in the Mk and Mo lineages, respectively. IL-3R expression is progressively and rapidly downmodulated in both E and Mk pathways, whereas it moderately decreases in the Mo lineage and is sustained in the G series. The expression of GM-CSFR is gradually downmodulated in all differentiation pathways, ie, the receptor density markedly decreases but late erythroblasts are still partially GM-CSFR+ and terminal G, Mk and Mo cells are essentially GM-CSFR+. Expression of receptors for late-acting cytokines is lineage-specific. Thus, EpoR, G-CSFR, TpoR, and M-CSFR exhibit a gradual induction followed by a sustained expression in the E, G, MK, and Mo lineages, respectively. In the other differentiation pathways the expression of these receptors is either absent or initially low and there-after suppressed. These observations are compatible with the following multi-step model. (1) The early-acting GFRs are expressed on quiescent HPCs with different patterns, whereas the multilineage GFRs are present on > or = 90% to 95% HPCs. (2) Multilineage GFs, potentiated by early-acting HGFs, trigger HPCs into cycling. HPC proliferation/differentiation is followed by declining expression of the early-acting GFRs and in part of multilineage GFRs (see above). (3) Multilineage GFs trigger the expression of the unilineage GFRs (see Testa U, et al: Blood 81:1442, 1993). Interaction of each unilineage GF with its receptor leads to sustained expression of the receptor (possibly via transcription factors activating the receptor promoter) and thus mediates differentiation/maturation through the pertinent lineage.