Ocrelizumab in a case of refractory chronic inflammatory demyelinating polyneuropathy with anti-rituximab antibodies.

Rituximab (RTX), a chimeric anti-CD20 monoclonal antibody, has demonstrated good efficacy as treatment in patients with resistant chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), but it is highly immunogenic due to its structure. Ocrelizumab (OCR) is a humanized anti-CD20 antibody, with higher tolerability and a lower immunogenic profile compared to RTX. We present a case of refractory CIDP effectively treated with OCR, switched from RTX after the development of anti-drug antibodies. A 25-year-old man was admitted to our clinic for the onset of distal upper and lower limb weakness and numbness, with electrodiagnostic criteria of CIDP. After several attempted standard CIDP treatments, RTX was introduced due to poor control of clinical relapses. Unfortunately, the patient developed a high anti-drug antibody titer after RTX infusion, with no control of disease. OCR was started as an off-label treatment, resulting in partial recovery from the last recurrence and achieving good prevention of new relapses with no adverse events. We suggest that OCR should be considered as another therapeutic option in refractory CIDP. In the literature, this is the first case of CIDP treated with OCR, demonstrating good efficacy for its anti-CD20 effect and better tolerability because of its lower immunogenicity.

Changes in the gene expression profile of gastric cancer cells in response to ibuprofen: a gene pathway analysis.

Nonsteroidal anti-inflammatory drugs possess antiproliferative activities that can affect cancer cells. The aim of this study was to examine the antiproliferative effects of ibuprofen on the MKN-45 cell line. Cells were treated with ibuprofen for 24, 48 or 72 h, and cell proliferation was evaluated by cell counting and [(3)H]-thymidine incorporation. Using microarray technology, we studied changes in the gene expression profiles over time after ibuprofen treatment. Ibuprofen induced a dose- and time-dependent reduction in cell number without altering cell viability. Genes involved in the 'biological oxidation' and 'G(1)/S checkpoint' pathways were the most significantly represented at 24 h, whereas genes involved in the 'cell cycle' and 'DNA replication' pathways were represented at 48 and 72 h. Genes associated with the 'apoptosis' pathway were also significantly represented at 72 h. Modulation of the expression of p53 and p53-induced genes (CDKN1A/p21 and GADD45), which are involved in the G(1)/S transition, suggested an effect of ibuprofen on cell-cycle progression. Using flow cytometry, we observed an early block in the G(1) phase of the cell cycle after ibuprofen treatment. In addition, P450 family transcripts were upregulated and intracellular reactive oxygen species (ROS) was increased following 12 h of ibuprofen treatment. Ibuprofen induced ROS, which resulted in cellular alterations that promoted a p53-dependent G(1) blockade. These findings suggest that ibuprofen exerts its antiproliferative actions through cell-cycle control and the induction of apoptosis. Both of these mechanisms appear to be independent of ibuprofen's anti-inflammatory effects.

tBid induces alterations of mitochondrial fatty acid oxidation flux by malonyl-CoA-independent inhibition of carnitine palmitoyltransferase-1.

Recent studies suggest a close relationship between cell metabolism and apoptosis. We have evaluated changes in lipid metabolism on permeabilized hepatocytes treated with truncated Bid (tBid) in the presence of caspase inhibitors and exogenous cytochrome c. The measurement of beta-oxidation flux by labeled palmitate demonstrates that tBid inhibits beta-oxidation, thereby resulting in the accumulation of palmitoyl-coenzyme A (CoA) and depletion of acetyl-carnitine and acylcarnitines, which is pathognomonic for inhibition of carnitine palmitoyltransferase-1 (CPT-1). We also show that tBid decreases CPT-1 activity by a mechanism independent of both malonyl-CoA, the key inhibitory molecule of CPT-1, and Bak and/or Bax, but dependent on cardiolipin decrease. Overexpression of Bcl-2, which is able to interact with CPT-1, counteracts the effects exerted by tBid on beta-oxidation. The unexpected role of tBid in the regulation of lipid beta-oxidation suggests a model in which tBid-induced metabolic decline leads to the accumulation of toxic lipid metabolites such as palmitoyl-CoA, which might become participants in the apoptotic pathway.

Metabolic profiling by 13C-NMR spectroscopy: [1,2-13C2]glucose reveals a heterogeneous metabolism in human leukemia T cells.

Metabolic profiling is defined as the simultaneous assessment of substrate fluxes within and among the different pathways of metabolite synthesis and energy production under various physiological conditions. The use of stable-isotope tracers and the analysis of the distribution of labeled carbons in various intermediates, by both mass spectrometry and NMR spectroscopy, allow the role of several metabolic processes in cell growth and death to be defined. In the present paper we describe the metabolic profiling of Jurkat cells by isotopomer analysis using (13)C-NMR spectroscopy and [1,2-(13)C(2)]glucose as the stable-isotope tracer. The isotopomer analysis of the lactate, alanine, glutamate, proline, serine, glycine, malate and ribose-5-phosphate moiety of nucleotides has allowed original integrated information regarding the pentose phosphate pathway, TCA cycle, and amino acid metabolism in proliferating human leukemia T cells to be obtained. In particular, the contribution of the glucose-6-phosphate dehydrogenase and transketolase activities to phosphoribosyl-pyrophosphate synthesis was evaluated directly by the determination of isotopomers of the [1'-(13)C], [4',5'-(13)C(2)]ribosyl moiety of nucleotides. Furthermore, the relative contribution of the glycolysis and pentose cycle to lactate production was estimated via analysis of lactate isotopomers. Interestingly, pyruvate carboxylase and pyruvate dehydrogenase flux ratios measured by glutamate isotopomers and the production of isotopomers of several metabolites showed that the metabolic processes described could not take place simultaneously in the same macrocompartments (cells). Results revealed a heterogeneous metabolism in an asynchronous cell population that may be interpreted on the basis of different metabolic phenotypes of subpopulations in relation to different cell cycle phases.

Partial purification and MALDI-TOF MS analysis of UN1, a tumor antigen membrane glycoprotein.

UN1 is a membrane glycoprotein that is expressed in immature human thymocytes, a subpopulation of peripheral T lymphocytes, the HPB acute lymphoblastic leukemia (ALL) T-cell line and fetal thymus. We previously reported the isolation of a monoclonal antibody (UN1 mAb) recognizing the UN1 protein that was classified as "unclustered" at the 5th and 6th International Workshop and Conference on Human Leukocyte Differentiation Antigens. UN1 was highly expressed in breast cancer tissues and was undetected in non-proliferative lesions and in normal breast tissues, indicating a role for UN1 in the development of a tumorigenic phenotype of breast cancer cells. In this study, we report a partial purification of the UN1 protein from HPB-ALL T cells by anion-exchange chromatography followed by immunoprecipitation with the UN1 mAb and MALDI-TOF MS analysis. This analysis should assist in identifying the amino acid sequence of UN1.

Oxaliplatin (L-OHP) treatment of human myeloma cells induces in vitro growth inhibition and apoptotic cell death.

Oxaliplatin (L-OHP), a diaminocyclohexane platinum derivative, is an active and well tolerated anticancer drug which is presently used in the treatment of gastrointestinal tumours. Since the efficacy of L-OHP in the treatment of multiple myeloma (MM) has not yet been evaluated, we studied the antiproliferative activity of this compound in vitro in a panel of MM cell lines (XG1, XG1a, U266 and IM-9). We found that L-OHP inhibited the growth of MM cells at therapeutically achievable concentrations (IC(50): 5-10 microM after 24 h of exposure) and was more active than Cisplatin (CDDP) or Carboplatin (CBDCA). The activity of L-OHP was apparently not affected by interleukin-6 (IL-6), the major growth and survival factor of MM cells. We also found that L-OHP induced apoptotic cell death. We demonstrated that the combination of L-OHP with Dexamethasone (Dex) resulted in the enhancement of the anti-myeloma effects. L-OHP and Dex both induced poly adenosine diphosphate (ADP)-ribose polymerase (PARP) cleavage and this induction was enhanced by the combined treatment. L-OHP-induced apoptosis correlated with caspase-3 cleavage, but this correlation could not be demonstrated in Dex-treated cells. Taken together, these in vitro results provide a rationale for the experimental use of L-OHP in the treatment of MM patients and suggest therapeutic combinations of potential value.

A novel monoclonal antibody recognizing human thymocytes and B-cell chronic lymphocytic leukemia cells.

This paper describes a new murine monoclonal antibody, UN5, raised against human thymocytes. This antibody recognizes a molecule of approximately 45 kDa on thymocytes. Flow cytometric analysis reveals a high intensity of labeling with the majority of thymocytes, whereas only CD20+ cells from peripheral whole-blood samples are weakly stained. Peripheral T cells, granulocytes, platelets and red blood cells do not express this antigen, while monocytes are only weakly labeled by UN5. Furthermore, the UN5 antibody discriminates between different types of B-cell malignancies, reacting with a subgroup of B-cell chronic lymphocytic leukemias and hairy cell leukemias, but not with the other kinds of hematopoietic malignancies tested. Antibody UN5 should prove a useful tool for the study of T-cell precursors and for analysis of both normal and neoplastic B cells.

Analysis of peripheral blood normal and malignant cells with the novel murine monoclonal antibody UN2.

The monoclonal antibody (mAb) UN2 was generated upon immunization of a Balb/c mouse with human thymocytes. mAb UN2 recognized an antigen expressed by a subpopulation of human thymocytes and peripheral blood lymphocytes. In thymus, mAb UN2 recognized cortical cells; its expression was higher on CD3bright than on CD3dim thymocytes. This antigen was also detected on peripheral blood granulocytes, monocytes, platelets and on cell lines MOLT4, U937 and KG1. mAb UN2 was submitted to the 5th International Workshop and Conference on Human Leukocyte Differentiation Antigens, Boston, MA, 1993, and was assigned to the CD31. Expression of the UN2-recognized antigen in malignant lymphoid cells from 57 cases of B-cell chronic lymphoproliferative disease and 4 of B-cell acute lymphoblastic leukemia was analysed in flow cytometry. Among the 57 cases of B-cell chronic lymphoproliferative malignancies studied, 49 were classified as B-cell chronic lymphocytic leukemia. These showed high (86 +/- 8%) UN2 antigen expression. In 8 cases of hairy-cell leukemia the percentage of cells reacting with mAb UN2 was 42 +/- 4%; the fluorescence intensity of labelled cells was lower than that displayed by cells of B-cell chronic lymphocytic leukemia and comparable to that of normal lymphoid cells. mAb UN2 could prove useful in analysis of the lymphoid development and diagnostics of B-cell chronic lymphoproliferative disorders.

Breast cancer estrogen and progesterone receptors.

Data from 2933 consecutive cases of primary breast carcinoma, observed in our Institute from 1984 to 1994, having documented estrogen (ER) and progesterone (PR) receptor levels, were obtained from the Institute's Hospital Tumor Registry and analysed after being categorised as follows: age, less than or equal to 60 vs. >60; menopausal status, pre-menopausal vs. post-menopausal; histology, ductal vs. lobular vs. others; tumor size, T-1 vs. T-2, T-3, T-4; nodal status, N-0, vs. N+; histologic grade, 1-2 vs. 3; focality, unifocal vs. multifocal; ER status, <10 fmol/mg protein vs. greater than or equal to 15. At multivariate analysis, using a logistic model including age, histology, tumor size, nodal status, histologic grade, uni-multifocality and PGF/ER status, significant associations were, for ER status: PGR status (OR = 34.01, 95% CI:20.08-57.80), histology (OR = 3.24, 95% CI:1.85-5.67), histologic grade (OR = 2.18, 95% CI:1.38-3.42), menopausal status (OR = 2.17, 95% CI:1.26-3.74), age (OR = 34.01, 95% CI:20.08-57.80), menopausal status (OR = 5.27, 95% CI:1.43-3.33), age (OR = 1.71, 95% CI:1.13-2.59). The finding that estrogen receptor positivity was more prevalent among tumors with lobular histology seems to suggest the possibility of fundamental differences in tumor biology ductal and lobular cancers.

Does a relationship exist between trends in estrogen receptor levels and breast cancer incidence and mortality?

Estrogen receptor data from 4,049 patients with primary breast cancer treated at the National Cancer Institute of Naples between 1984 and 1996, have been evaluated to analyze temporal trend of this tumor marker. The prevalence rate of estrogen receptor levels falls from >75% in women older than 60 years to <70% in younger patients. The analysis of these data by birth cohort shows a trend very similar to that of breast cancer incidence in Italy, suggesting that the breast cancer appearance could be modulated in different period of life.

Epidermal growth factor receptor in human breast cancer comparison with steroid receptors and other prognostic factors.

The relationship between epidermal growth factor receptor (EGFR) status and various prognostic factors was investigated in 70 human breast cancer specimens. Epidermal growth factor receptor was determined by radioligand binding assay, standardized by the EORTC Receptor Study Group, using hydroxyapatite to separate receptor-bound and free ligand. The percentage of EGFR positivity was 80% when the cutoff was set at 5 fmol/mg of membrane protein; this percentage was among the highest hitherto reported. Regression analysis of EGFR versus ER and PR levels confirmed an inverse relationship between EGFR and ER (p = 0.022) as well as between EGFR and PR (p = 0.024). Univariate analysis of the EGFR data stratified according to steroid hormone receptor status showed EGFR to be negatively associated with ER and PR. No association was found between EGFR and menopausal status, axillary lymph node involvement, tumor size, and differentiation grade. A direct association between EGFR status and Ki-67 positive cell rate could be demonstrated.

Generating initial models for reasoning.

Much of the knowledge that children and adults have about the world resides in intuitive models. Previous work shows that intuitive models allow for computation of specific outcomes given information about the system, but little is known about how such models are acquired. The current study tested three hypotheses about how children and adults construct intuitive models when they encounter a new property: (1) intuitive models are constructed by transferring principles from familiar properties; (2) with development, children shift from applying a default model to constructing specialized models; and (3) younger children's model construction is constrained by the domain, but becomes increasingly domain independent with development. Participants from three age groups (10, 13, and 19 years) made a series of judgments about two familiar properties and one novel property. Causal models showed that all age groups transferred principles from the familiar properties to the novel property. None of the age groups used a default model. There was developmental change in the effect of domain; younger, but not older, children's models were affected by domain. These findings suggest that the transfer process is developmentally invariant but that constraints on the process (i.e., domain dependence and understanding of base models) change with development.

UN1, a murine monoclonal antibody recognizing a novel human thymic antigen.

A murine monoclonal antibody (mAb) UN1 was produced on the basis of selective reactivity with human thymocytes. Characterization of UN1 by immunofluorescence gave a high intensity of labeling with the majority of human thymocytes. Expression was preferentially associated with immature thymocytes (CD3dim) compared to mature cells, whereas only a subpopulation of peripheral blood lymphocytes was weakly stained. No specific binding to monocytes or granulocytes was detected. The T-cell lines HPB-ALL, H9 and MOLT-4 were all positively bound by UN1. Immunohistological staining of thymic tissues showed that mAb UN1 detected cells in both the cortex and medulla of fetal thymus, whereas the reaction in thymus samples from young children was mainly with medullar cells. By western blotting analysis, the antigen recognized by mAb UN1 corresponds to a membrane polypeptide with a molecular weight of approximately 120 kDa present on thymocytes and HPB-ALL cells. The mAb UN1 was submitted to the 5th International Workshop and Conference on Human Leukocyte Differentiation Antigens, Boston, 1993. UN1 did not cluster in any of the old or new clusters of differentiation discussed at the conference, indicating its unique reactivity. Together with the data presented in this paper, this suggests that the UN1 antibody defines a previously undescribed molecule present on the cell surface of thymocytes and a minority of peripheral blood lymphocytes.

UN-1, a murine monoclonal antibody recognizing a human thymocyte undescribed antigen.

A monoclonal antibody (MoAb), UN-1, specific for a human thymocyte cell surface antigen was produced. The same MoAb recognized in immunofluorescence also cells of the human T line HPB-ALL, while did not bind human peripheral blood cells and cells of some T, B and myeloid lines. Western blotting analysis of thymocyte membranes with MoAb UN-1 revealed a structure with a molecular weight of 150 kDa. Therefore both the pattern of expression and the size of the antigen recognized by MoAb UN-1 did not correspond to any previously described cell surface molecule.

CD69 expression on primitive progenitor cells and hematopoietic malignancies.

CD69 is an early activation antigen of peripheral blood lymphocytes and is constitutively expressed on a wide variety of bone marrow-derived cells. To further characterize the distribution and understand the potential biological role of the molecule in normal and malignant hematopoiesis, we used a novel high affinity anti-CD69 mAb (UN6) and analyzed hematopoietic progenitor cells together with a panel of myeloid and lymphoid malignancies. We report that mobilized peripheral blood CD34+ cells display detectable levels of CD69 and that the density of membrane expression correlates with the immature phenotype CD34bright Thy-1bright cells. Furthermore, during cytokine-induced differentiation, the expression of CD69 is moderately down-regulated. Analysis of hematopoietic malignancies revealed that CD69 expression correlates with the immature myeloid phenotype. Taken together these data suggest a role of CD69 during the early phase of hematopoiesis and in the leukemic transformation.

Triggering of CD40 antigen inhibits fludarabine-induced apoptosis in B chronic lymphocytic leukemia cells.

We analyzed the effect of CD40 triggering on the fludarabine-induced apoptosis of B chronic lymphocytic leukemia (B-CLL) cells. Peripheral blood samples obtained from 15 patients were incubated with fludarabine in the absence or the presence of the anti-CD40 monoclonal antibody (MoAb) G28-5. In 12 patients a significant proportion of apoptotic cells, ranging from 22% to 38% (mean +/- SE: 28.5 +/- 1.6), were detected after 3 days of culture. In 9 of these samples, the addition of G28-5 reduced apoptosis by at least 30.1% and by 57.1% +/- 7.8% on average (P = .0077). Because the CD40 antigen activates NF-kappaB/Rel transcription factors in B cells, and NF-kappaB/Rel complexes can inhibit cell apoptosis, we investigated whether the antiapoptotic effect of G28-5, in our system, could be related to modulation of NF-kappaB/Rel activity. As expected, B-CLL cells displayed significant levels of nuclear NF-kappaB/Rel activity; p50, RelA, and c-Rel components of the NF-kappaB/Rel protein family were identified in these complexes. After exposure to fludarabine, NF-kappaB/Rel complexes were decreased in the nuclei. The addition of G28-5 upregulated the NF-kappaB/Rel levels. To determine the involvement of NF-kappaB/Rel activity in the G28-5-mediated inhibition of apoptosis, we blocked the transcription factor with a decoy oligonucleotide, corresponding to the NF-kappaB/Rel consensus sequence. Cells incubated with the anti-CD40 MoAb in the presence of the decoy oligonucleotide but not a control oligonucleotide displayed a complete impairment of the G28-5 antiapoptotic effect, indicating that NF-kappaB/Rel activity was required for the inhibition of apoptosis. These results suggest that CD40 triggering in vivo could counteract the apoptotic effect of fludarabine on B-CLL cells and that its neutralization, or the use of NF-kappaB/Rel inhibitors, could improve the therapeutic effect of fludarabine.

CD36 is rapidly and transiently upregulated on phytohemagglutinin (PHA)-stimulated peripheral blood lymphocytes. Analysis by a new monoclonal antibody (UN7).

The monoclonal antibody (mAb) UN7, clustered as an anti-CD36 mAb, has been used to test the cell surface expression of CD36 on peripheral blood lymphocytes (PBL) following mitogenic stimulation. CD36, scarcely expressed on resting cell membranes, was rapidly upregulated on PBL after phytohemagglutinin (PHA) stimulation. The antigen was detected on the cell surface after 15 min of stimulation, increased rapidly by 60 min and peaked between 3 and 12 h, declining thereafter. The inhibition of protein synthesis by cycloheximide did not modify the PHA-induced expression of CD36. Neither the anti-CD3 OKT3 mAb nor the anti-CD2 BIL 2.29 and 9.1 mAbs induced any significant upregulation of the molecule. The addition of anti-CD28 15E8 mAb or IL-2 or IFN-gamma to PHA or anti-CD3 or anti-CD2 mAbs did not influence the pattern of CD36 expression. The phorbol-2-myristate-13-acetate (PMA), alone or in combination with ionomycin, was unable to activate the expression of CD36, while it inhibited the PHA-induced upregulation. The PHA-induced upregulation of CD36 was partially inhibited by the addition of LY294002 or wortmannin, while not affected by that of calphostin C. Thus, CD36 was found to be early and transiently upregulated by PHA stimulation on PBL. The rapid modulation of the molecule was not related to new protein synthesis, but was probably due to the insertion into the plasma membrane of a presynthetized protein pool.

Purification and characterization of a human sialoglycoprotein antigen expressed in immature thymocytes and fetal tissues.

The monoclonal antibody UN1 was previously produced in our laboratory on the basis of selective reactivity with human thymocytes and has been classified as unclustered by the 5th and 6th International Workshop and Conference on Human Leukocyte Differentiation Antigens. The antigen recognized by mAb UN1 was found to be expressed on the cell surface of immature human thymocytes, a subpopulation of peripheral T lymphocytes and on several fetal tissues including thymus. The UN1 antigen is purified from children's thymus by ion-exchange and affinity chromatography. Two-dimensional electrophoresis shows that the purified antigen displays microheterogeneity appearing as multiple spots over a pI range 4.4-5.0 at 100-120 kDa. Treatment with neuraminidase results in a retarded migration in SDS-PAGE, an increase in isoelectric point and a reduction in carbohydrate content, indicating a substantial content of sialic acid. Glycosidase digestion and lectin-binding analysis indicate that the carbohydrate residues are essentially O-linked. A preliminary analysis has detected the UN1 antigen in human breast carcinoma tissues but not in normal breast. The biochemical features and the pattern of expression of the UN1 antigen indicate that this molecule may have the characteristics typical of the family of cell-membrane-associated mucin-like glycoproteins; a number of these molecules are thought to have a role in cell-cell interaction, tumor progression and metastasis.

Identification by differential display of transcripts regulated during hematopoietic differentiation.

The polymerase chain reaction-based differential display method (DDRT-PCR) was used to identify mRNAs differentially expressed during the maturation of human CD34+ progenitor cells stimulated to differentiate in vitro towards granulomonocytic or erythroid lineages with a mixture of hemopoietins (kit ligand + interleukin 3 + GM-CSF in the absence or presence of erythropoietin, respectively). Three cDNA transcripts (B32, B41, and B56) display differential expression during cytokine-induced maturation of CD34+ cells. These clones have no homology with already-described sequences. Primer extension cofirmed the presence of the corresponding mRNA. The levels of mRNA corresponding to B32 are enhanced in the later phases of the granulomonocytic as well as in the erythroid differentiation of CD34+ cells. The mRNA identified by B41 was induced by a late stage in only granulomonocytic differentiation of CD34+ cells. The mRNA corresponding to B56 was instead present in nonstimulated CD34+ cells, declined in the early stages of differentiation, and reappeared at later stages in cells treated with both combinations of cytokines. Expression of these genes was detected in a number of acute myelogenous leukemias, as well as in some leukemic cell lines. B32 and B41 were downregulated in KG-1 cells induced to differentiate towards the monocytic lineage, whereas the levels of B56 were unchanged. In K562 cells, clones B41 and B56 were downregulated only in the late phases of PMA-induced megakaryocytic differentiation and during erythroid differentiation. B32 was rapidly downregulated when K562 cells were induced to differentiate towards either megakaryocytic or erythroid phenotypes. These transcripts represent novel hematopoietic cDNAs that should prove of value for the study of human blood cells and their disorders.