Peripheral T-cell lymphoma with t(6;14)(p25;q11.2) translocation presenting with massive splenomegaly.

Recurrent chromosomal translocations associated to peripheral T-cell lymphomas (PTCL) are rare. Here, we report a case of PTCL, not otherwise specified (NOS) with the karyotype 46,Y,add(X)(p22),t(6;14)(p25;q11) and FISH-proved breakpoints in the IRF4 and TCRAD loci, leading to juxtaposition of both genes. A 64-year-old male patient presented with mild cytopenias and massive splenomegaly. Splenectomy showed diffuse red pulp involvement by a pleomorphic medium- to large-cell T-cell lymphoma with a CD2+ CD3+ CD5- CD7- CD4+ CD8+/- CD30- TCRbeta-F1+ immunophenotype, an activated cytotoxic profile, and strong MUM1 expression. The clinical course was marked by disease progression in the bone marrow under treatment and death at 4 months. In contrast with two t(6;14)(p25;q11.2)-positive lymphomas previously reported to be cytotoxic PTCL, NOS with bone marrow and skin involvement, this case was manifested by massive splenomegaly, expanding the clinical spectrum of PTCLs harboring t(6;14)(p25;q11.2) and supporting consideration of this translocation as a marker of biological aggressiveness.

Characterization of the tonoplast Ca2+/H+ antiport system from maize roots.

The tonoplast calcium Ca2+/H+ antiport system of maize (Zea mays L. cv LG 11) roots was characterized using the ''pH jump'' technique in order to avoid interference from the tonoplast proton and Ca2+ pumps. Ca2+ uptake was recorded in the presence of different inhibitors and divalent ions. Chemical modification of amino acid residues of the antiport was used to elucidate the amino acid residues participating in the Ca2+ transport activity. The Ca2+/H+ antiport activity was found to be strongly inhibited by ruthenium red and verapamil, whereas diethylstilbestrol was less effective. Vanadate, erythrosin B, cyclopiazonic acid, bafilomycin, thapsigargin, N,N'-dicyclohexylcarbodiimide (DCCD) and 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS) were without effect. Lanthanum and divalent ions were strongly inhibitory (Cd2+ > Mn2+ > Sr2+ > Ba2+). While reagents modifying sulfhydryl groups (N-ethylmaleimide and 5,5'-dithio-bis(2-nitrobenzoate)) did not affect the antiport activity, modification of trytophan residues (N-bromosuccinimide) was strongly inhibitory. We conclude that ruthenium red, verapamil, lanthanum and divalent cations directly inhibit Ca2+ uptake independent of the function of the proton and Ca2+ pumps. Moreover, the results of chemically modified amino acid residues suggest that sulfhydryl groups are not involved in Ca2+ transport, while tryptophan residues seem important for this translocation.

Imaging of human leukemic T-cell xenografts in nude mice by radiolabeled monoclonal antibodies and F(ab')2 fragments.

Monoclonal antibodies (MoAb) that react with the T-lymphocyte markers called cluster of differentiation CD5 and CD2 were labeled with iodine 131 (131I) and were injected intravenously in nude mice bearing solid subcutaneous xenografts derived from the human T-cell leukemia line Ichikawa. Both MoAb anti-CD5 and anti-CD2 yielded favorable mean tumor to whole-body ratios of 3.8 and 5.1, respectively. These ratios were further increased up to 10.0 for MoAb anti-CD5 and 15.5 for MoAb anti-CD2 by using their F(ab')2 fragments. The tumors could be imaged clearly by external scanning after injection of F(ab')2 fragments from both MoAb. F(ab')2 fragments from MoAb anti-CD2 and of a third MoAb recognizing the clonotypic determinant (Ti) of the antigen receptor expressed by the human T-cell line Jurkat were injected in mice bearing intrasplenic Jurkat xenografts. A selective localization of both fragments in tumor tissue was demonstrated with mean tumor to whole-body ratios of 7.5 and 4.1 for MoAb anti-CD2 and anti-Ti, respectively. These in vivo experimental results may provide useful information for the potential use of radiolabeled MoAb and fragments in the diagnosis and treatment of patients with T-cell lymphoma and different other forms of T-cell malignancies.

A gating mutation in the internal pore of ASIC1a.

Using a substituted cysteine accessibility scan, we have investigated the structures that form the internal pore of the acid-sensing ion channel 1a. We have identified the amino acid residues Ala-22, Ile-33, and Phe-34 in the amino terminus and Arg-43 in the first transmembrane helix, which when mutated into cysteine, were modified by intracellular application of MTSET, resulting in channel inhibition. The inhibition of the R43C mutant by internal MTSET requires opening of the channel. In addition, binding of Cd2+ ions to R43C slows the channel inactivation. This indicates that the first transmembrane helix undergoes conformational changes during channel inactivation. The effect of Cd2+ on R43C can be obtained with Cd2+ applied at either the extracellular or the intracellular side, indicating that R43C is located in the channel pore. The block of the A22C, I33C, and F34C mutants by MTSET suggests that these residues in the amino terminus of the channel also participate to the internal pore.

Role of intracellular cysteines in ENaC function

The epithelial sodium channel (ENaC) regulates the sodium reabsorption in the collecting duct principal cells of the nephron. ENaC is mainly regulated by hormones such as aldosterone and vasopressin, but also by serine proteases, Na+ and divalent cations. The crystallization of an ENaC/Deg member, the Acid Sensing Ion Channel, has been recently published but the pore-lining residues constitution of ENaC internal pore remains unclear. It has been reported that mutation aS589C of the selectivity filter on the aENaC subunit, a three residues G/SxS sequence, renders the channel permeant to divalent cations and sensitive to extracellular Cd2+. We have shown in the first part of my work that the side chain of aSer589 residue is not pointing toward the pore lumen, permitting the Cd2+ to permeate through the ion pore and to coordinate with a native cysteine, gCys546, located in the second transmembrane domain of the gENaC subunit. In a second part, we were interested in the sulfhydryl-reagent intracellular inhibition of ENaC-mediated Na+ current. Kellenberger et al. have shown that ENaC is rapidly and reversibly inhibited by internal sulfhydryl reagents underlying the involvement of intracellular cysteines in the internal regulation of ENaC. We set up a new approach comprising a Substituted Cysteine Analysis Method (SCAM) using intracellular MTSEA-biotin perfusion coupled to functional and biochemical assays. We were thus able to correlate the cysteine-modification of ENaC by methanethiosulfonate (MTS) and its effect on sodium current. This allowed us to determine the amino acids that are accessible to intracellular MTS and the one important for the inhibition of the channel. RESUME : Le canal épithélial sodique ENaC est responsable de la réabsorption du sodium dans les cellules principales du tubule collecteur rénal. Ce canal est essentiellement régulé par voie hormonale via l'aldostérone et la vasopressine mais également par des sérines protéases, le Na+ lui-même et certains cations divalents. La cristallisation du canal sodique sensible au pH acide, ASIC, un autre membre de la famille ENaC/Deg, a été publiée mais les acides aminés constituant le pore interne d'ENaC restent indéterminés. Il a été montré que la mutation aS589C du filtre de sélectivité de la sous-unité aENaC permet le passage de cations divalents et l'inhibition du canal par le Cd2+ extracellulaire. Dans un premier temps, nous avons montré que la chaîne latérale de la aSer589 n'est pas orientée vers l'intérieur du pore, permettant au Cd2+ de traverser le canal et d'interagir avec une cysteine native du second domaine transrnembranaire de la sous-unité γENaC, γCys546. Dans un second temps, nous nous sommes intéressés au mécanisme d'inhibition d'ENaC par les réactifs sulfhydryl internes. Kellenberger et al. ont montré l'implication de cystéines intracellulaires dans la régulation interne d'ENaC par les réactifs sulfhydryl. Nous avons mis en place une nouvelle approche couplant la méthode d'analyse par substitution de cystéines (SCAM) avec des perfusions intracellulaires de MTSEAbiotine. Ainsi, nous pouvons meure en corrélation les modifications des cystéines d'ENaC par les réactifs methanethiosulfonates (MTS) avec leur effet sur le courant sodique, et donc mettre en évidence les acides aminés accessibles aux MTS intracellulaires et ceux qui sont importants dans la fonction du canal.

Cyst-based ecotoxicological tests using Anostracans: comparison of two species of Streptocephalus

Cyst-based ecotoxicological tests are simple and low-cost methods for assessing acute toxicity. Nevertheless, only a few comparative studies on their sensitivity are known. In the present study, the suitability of the use of two freshwater Anostracan species, Streptocephalus rubricaudatus and S. texanus, was assessed. The impact of 16 priority pollutants (4 heavy metals, 11 organic, and 1 organometallic compounds) on these two species, as well as on Artemia salina (Artoxkit M), Daphnia magna (International Organization for Standardization 6341), and S. proboscideus (Streptoxkit F) was assessed. For indicative comparison, bioassays using Brachionus calyciflorus (Rotoxkit F) and Photobacterium phosphoreum (Microtox) were also performed. For heavy metals (K2Cr2O7, Cd2+, Zn2+, Cu2+), the sensitivity of the two studied Streptocephalus species was slightly higher than that of D. magna. It was significantly more elevated than for the marine A. salina. For organic and organometallic micropollutants [phenol, 3,5-dichlorophenol, pentachlorophenol (PCP), hydroquinone, linear alkylbenzene sulfonate, sodium dodecyl sulfate, tributylphosphate, dimethylphthalate, atrazine, lindane, malathion, tributyltin chloride (TBT-Cl)], the sensitivity of the 4 anostracan species was of the same order of magnitude as that of D. magna. Artemia salina was slightly less sensitive to some organic compounds (PCP, hydroquinone, TBT-Cl). The sensitivity of S. rubricaudatus to organic solvents was low. On the other hand, this anostracan was quite sensitive to NaCl. Thus, its use is restricted to freshwater samples. The evaluation of global practicability of these two tests confirms that cyst-based freshwater anostracans may be used to perform low-cost tests at a sensitivity comparable to that of D. magna (24 h immobilization test).

Spinal cord T-cell infiltration in the spared nerve injury model of neuropathic pain: a time course study

Background : Numerous studies have shown that immune cells infiltrate the spinal cord after peripheral nerve injury and that they play a major contribution to sensory hypersensitivity in rodents. In particular, the role of monocyte-derived cells and T lymphocytes seems to be prominent in this process. This exciting new perspective in research on neuropathic pain opens many different areas of work, including the understanding of the function of these cells and how they impact on neural function. However, no systematic description of the time course or cell types that characterize this infiltration has been published yet, although this seems to be the rational first step of an overall understanding of the phenomenon. Objective : Describe the time course and cell characteristics of T lymphocyte infiltration in the spinal cord in the Spared Nerve Injury (SNI) model of neuropathic pain in rats. Methods : Collect of lumbar spinal cords of rats at days 2, 7, 21 and 40 after SNI or sham operation (n=4). Immunofluorescence detecting different proteins of T cell subgroups (CD2+CD4+, CD2+CD8+, Th1 markers, Th2 markers, Th17 markers). Quantification of the infiltration rate of the different subgroups. Expected results : First, we expect to see an infiltration of T cells in the spinal cord ipsilateral to nerve injury, higher in SNI rats than in sham animals. Second, we anticipate that different subtypes of T cells penetrate at different time points. Finally, the number of T lymphocytes are expected to decrease at the latest time point, showing a resolution of the process underlying their infiltrating the spinal cord in the first place. Impact : A systematic description of the infiltration of T cells in the spinal cord after peripheral nerve injury is needed to have a better understanding of the role of immune cells in neuropathic pain. The time course that we want to establish will provide the scientific community with new perspectives. First, it will confirm that T cells do indeed infiltrate the spinal cord after SNI in rats. Second, the type of T cells infiltrating at different time points will give clues about their function, in particular their inflammatory or anti-inflammatory profile. From there on, other studies could be lead, investigating the functional side of the specific subtypes put to light by us. Ultimately, this could lead to the discovery of new drugs targeting T cells or their infiltration, in the hope of improving neuropathic pain.

Heavy metal ions are potent inhibitors of protein folding.

Environmental and occupational exposure to heavy metals such as cadmium, mercury and lead results in severe health hazards including prenatal and developmental defects. The deleterious effects of heavy metal ions have hitherto been attributed to their interactions with specific, particularly susceptible native proteins. Here, we report an as yet undescribed mode of heavy metal toxicity. Cd2+, Hg2+ and Pb2+ proved to inhibit very efficiently the spontaneous refolding of chemically denatured proteins by forming high-affinity multidentate complexes with thiol and other functional groups (IC(50) in the nanomolar range). With similar efficacy, the heavy metal ions inhibited the chaperone-assisted refolding of chemically denatured and heat-denatured proteins. Thus, the toxic effects of heavy metal ions may result as well from their interaction with the more readily accessible functional groups of proteins in nascent and other non-native form. The toxic scope of heavy metals seems to be substantially larger than assumed so far.

EAACI IG Biologicals task force paper on the use of biologic agents in allergic disorders.

Biologic agents (also termed biologicals or biologics) are therapeutics that are synthesized by living organisms and directed against a specific determinant, for example, a cytokine or receptor. In inflammatory and autoimmune diseases, biologicals have revolutionized the treatment of several immune-mediated disorders. Biologicals have also been tested in allergic disorders. These include agents targeting IgE; T helper 2 (Th2)-type and Th2-promoting cytokines, including interleukin-4 (IL-4), IL-5, IL-9, IL-13, IL-31, and thymic stromal lymphopoietin (TSLP); pro-inflammatory cytokines, such as IL-1β, IL-12, IL-17A, IL-17F, IL-23, and tumor necrosis factor (TNF); chemokine receptor CCR4; and lymphocyte surface and adhesion molecules, including CD2, CD11a, CD20, CD25, CD52, and OX40 ligand. In this task force paper of the Interest Group on Biologicals of the European Academy of Allergy and Clinical Immunology, we review biologicals that are currently available or tested for the use in various allergic and urticarial pathologies, by providing an overview on their state of development, area of use, adverse events, and future research directions.

Cerebriforms cells in cerebrum: an unusual finding

Background. Mycosis Fungoides (MF) is the most common cutaneous T-cell lymphoma, and large cell trasformation (tMF) is an adverse prognostic event. Extra-cutaneous dissemination can occur in the course of the disease, but dissemination to the central nervous system (CNS) is uncommon. Moreover, CNS lymphomas are overall rare and most often of B-cell phenotype. We report a case of CNS large T-cell lymphoma presenting as multiple cerebral lesions in a patient with a history of MF. Methods. We report a case of a 33-year-old woman, known since the age of 16 for erythematous plaques thought to be atopic dermatitis, who developed, end 2012, multiple nodular skin lesions and peripheral adenopathies. Two skin lesions were biopsied simultaneously, and diagnosed as MF and tMF. A lymph node biopsy showed dermatopathic changes without lymphoma (Stage IIB). She received local treatment (UVB, PUVA and radiation therapy) and interferon therapy, and experienced almost complete remission. In 2015 neurological symptoms lead to evidence multiple cerebral lesions, suspicious for lymphoma, evaluated by stereotaxic biopsies. We compared histopathological and molecular features of these with previous skin specimens. After negative bone marrow staging biopsy, she was recently started on chemotherapy (MATRIX). Short follow-up shows rapidly worsening clinical conditions. Results. One of the initial skin biopsies showed atypical lymphoid cells with epidermotropism, Pautrier abcesses and CD4+ CD30- phenotype; the other revealed diffuse dermal infiltration by predominantly large cerebriform tumor cells with high proliferative fraction, and CD2−CD3 −CD4+/−CD7−CD30+ALK- EMA- non-cytotoxic immunophenotype. Altogether, these results led us to diagnose MF and tMF, respectively. The brain was infiltrated by large atypical lymphoid cells with cerebriform nuclei, somewhat anaplastic features and perivascular distribution. By immunohistochemistry, tumor cells were highly proliferative, with a CD2−CD3+CD5−CD7+CD30+ activated cytotoxic immunophenotype. A diagnosis of CD30+ cytotoxic peripheral T-cell lymphoma was retained. TRG and TRB clonality analyses revealed clonal rearrangements in skin and CNS biopsies, with identical patterns in both skin specimens but only minimally overlapping profiles when compared to the CNS sample. Der Pathologe 6 ? 2015 | 633 Conclusions. The reported case illustrates an uncommon finding of a CNS T-cell lymphoma in a patient with previous MF, questioning the clonal relationship between the two diseases and challenging the adequate classification of this CNS lymphoma as either a progression or a de novo lymphoma. Despite differences in immunophenotype and clonality patterns, this CNS lymphoma could possibly represent an aggressive divergent evolution of a primary cutaneous T-cell lymphoma. Additional sequencing is ongoing to try to solve the question.

Spinal Cord T-Cell Infiltration in the Rat Spared Nerve Injury Model: A Time Course Study.

The immune system is involved in the development of neuropathic pain. In particular, the infiltration of T-lymphocytes into the spinal cord following peripheral nerve injury has been described as a contributor to sensory hypersensitivity. We used the spared nerve injury (SNI) model of neuropathic pain in Sprague Dawley adult male rats to assess proliferation, and/or protein/gene expression levels for microglia (Iba1), T-lymphocytes (CD2) and cytotoxic T-lymphocytes (CD8). In the dorsal horn ipsilateral to SNI, Iba1 and BrdU stainings revealed microglial reactivity and proliferation, respectively, with different durations. Iba1 expression peaked at D4 and D7 at the mRNA and protein level, respectively, and was long-lasting. Proliferation occurred almost exclusively in Iba1 positive cells and peaked at D2. Gene expression observation by RT-qPCR array suggested that T-lymphocytes attracting chemokines were upregulated after SNI in rat spinal cord but only a few CD2/CD8 positive cells were found. A pronounced infiltration of CD2/CD8 positive T-cells was seen in the spinal cord injury (SCI) model used as a positive control for lymphocyte infiltration. Under these experimental conditions, we show early and long-lasting microglia reactivity in the spinal cord after SNI, but no lymphocyte infiltration was found.