Extended RET gene analysis in patients with apparently sporadic medullary thyroid cancer: clinical benefits and cost.

RET sequencing has become an important tool in medullary thyroid cancer (MTC) evaluation and should be performed even in the absence of family history of MTC. The most commonly studied exons in index cases are 8, 10, 11, and 13-16. To address the ATA guidelines regarding the sequencing of the entire coding region of RET, we selected 50 patients with sporadic MTC (sMTC) without mutations in the hot spot regions of RET for extended investigation of exons 1-7, 9, 12, 17, 18, and 19. Twenty-seven of 50 patients presented with one or more features suggesting familial disease. We found only a new RET variant (p.Gly550Glu) in one patient with MTC. Several polymorphisms were observed, and their frequency was histogram scaled by exons and introns. Eight patients were also included for somatic mutation search. We estimated the sequencing cost by stratifying into four investigation approaches: (1) hot spot exons in a new patient, (2) the remaining exons if the hot spots are negative in a patient with suspected familial disease, (3) a relative of a carrier for a known RET mutation, and (4) tumor sequencing. In spite of the increasing number of variants being described in MTC, it appears that there is no direct clinical benefit in extending RET germ line analysis beyond the hot spot regions in sMTC. The cost evaluation in apparent sMTC using a tiered approach may help clinicians make more suitable decisions regarding the benefits of investigating only the hot spots against the entire coding region of RET.

Probing the metal-insulator phase transition in the (DMEDO-EBDT)2PF6 single crystal by optical measurements.

The temperature and polarization dependence of the optical reflectivity  spectra of a quasi-one-dimensional 1/4-filled band system, (DMEDO-EBDT)(2)PF(6), have been investigated. We observed clear anisotropy in the electronic structures corresponding to the anisotropic transport properties. The appearance of a charge gap (E(g) > 0.1 eV) and transfer of the spectral weight accompanied by the metal-insulator phase transition were clearly observed. In addition, a split of the intramolecular vibrational modes was observed, which strongly suggested the existence of charge disproportionation in the low temperature phase. We also observed a photoinduced reflectivity change, which implied the occurrence of a photoinduced phase transition from the low temperature insulating phase to the high temperature metallic phase.

Molecular paramagnetic semiconductor: crystal structures and magnetic and conducting properties of the Ni(dmit)(2) salts of 6-oxoverdazyl radical cations (dmit = 1,3-dithiol-2-thione-4,5-dithiolate).

Four kinds of 1:1 and 1:3 salts of 3-[4-(trimethylammonio)phenyl]-1,5-diphenyl-6-oxoverdazyl radical cation ([1](+)) and its mono- and dimethyl derivatives ([2](+) and [3](+)) with Ni(dmit)(2) anions (dmit = 1,3-dithiol-2-thione-4,5-dithiolate) ([1](+)[Ni(dmit)(2)](-) (4), [2](+)[Ni(dmit)(2)](-) (5), [3](+)[Ni(dmit)(2)](-) (6), and [1](+)[Ni(dmit)(2)](3)(-) (7)) have been prepared, and the magnetic susceptibilities (chi(M)) have been measured between 1.8 and 300 K. The chi(M) values of salts 5 and 7 can be well reproduced by the sum of the contributions from (i). a Curie-Weiss system with a Curie constant of 0.376 (K emu)/mol and negative Weiss constants (THETAV;) of -0.4 and -1.7 K and (ii). a dimer system with strong negative exchange interactions of 2J/k(B) = -354 and -258 K, respectively. The dimer formations in Ni(dmit)(2) anions have been ascertained by the crystal structure analyses of salts 4-6. In salts 4 and 6, Ni(dmit)(2) dimer molecules are sandwiched between two verdazyl cations, indicating the formation of a linear tetramer in 4 and 6. The magnetic susceptibility data for salts 4 and 6 have been fitted to a linear tetramer model using an end exchange interaction of 2J(1)/k(B) = -600 K and a central interaction of 2J(2)/k(B) = -280 K for 4 and 2J(1)/k(B) = -30 K and 2J(2)/k(B) = -580 K for 6, respectively. The results of the temperature dependence of the g(T) value in salts 4-6 obtained by ESR measurement also support the above analyses. The 1:1 salts 4-6 are insulators. On the other hand, the conductivity of the 1:3 salt 7 at 20 degrees C was sigma = 0.10 S cm(-)(1) with an activation energy E(A) = 0.099 eV, showing the semiconductor property. Salt 7 is a new molecular paramagnetic semiconductor.

Systemic lupus erythematosus and thrombotic thrombocytopenic purpura: a case report and literature review.

We describe a patient with systemic lupus erythematosus (SLE) who developed severe and acute thrombotic thrombocytopenic purpura (TTP). Detection of the fragmentation of peripheral red blood cells (RBC) helped the early diagnosis of TTP and the patient was rescued by extensive plasma exchange started promptly after the diagnosis. Because manifestations of TTP are similar to those in SLE, it is sometimes difficult to make an accurate diagnosis of TTP in SLE patients. We emphasise here the significance of the early diagnosis of TTP by the observation of fragmented RBC and the intensive therapy, including plasma exchange, for this very severe condition.

Magnetic semiconductor: structural, magnetic, and conducting properties of the salts of the 6-oxoverdazyl radical cation with M(dmit)(2) anions (M = Ni, Zn, Pd, and Pt, dmit = 1,3-dithiol-2-thione-4,5-dithiolate).

Five kinds of (1:1), (1:3), and (2:1) salts of 3-[4-(diethylmethylammonio)phenyl]-1,5-diphenyl-6-oxoverdazyl radical cation [V](+) with M(dmit)(2) anions (M = Ni, Zn, Pd, and Pt, dmit = 1,3-dithiol-2-thione-4,5-dithiolate) ([V](+)[Ni(dmit)(2)](-) (1), [V](+)[Ni(dmit)(2)](3)(-) (2), [V](+)(2)[Zn(dmit)(2)](2-) (3), [V](+)(2)[Pd(dmit)(2)](2-) (4), and [V](+)(2)[Pt(dmit)(2)](2-) (5)) and an iodide salt of [V](+) ([V](+)[I](-) (6)) have been prepared, and the magnetic susceptibilities (chi(M) values) have been measured between 1.8 and 300 K. The chi(M) of the (1:1) Ni salt (1) can be well reproduced by the sum of the contributions from (i) a Curie-Weiss system with a Curie constant (C) of 0.376 K emu/mol and a negative Weiss constant (theta) of -1.5 K and (ii) the one-dimensional Heisenberg antiferromagnetic alternating chain system with 2J(A-B)/k(B) = -274 K (alternation parameter alpha = J(A-C)/J(A-B) = 0.2). The chi(M) of the (1:3) Ni salt (2) can be well explained by the two-term contributions from (i) the Curie-Weiss system with C = 0.376 K emu/mol and theta = -5.0 K and (ii) the dimer system with 2J/k(B) = -258 K. The magnetic properties of 1 and 2 were discussed based on the results obtained by crystal structure analysis and ESR measurements of 1 and 2. The chi(M) values of the (2:1) Zn, Pd, Pt salts 3, 4, and 5 and [V](+)[I](-) salt 6 follow the Curie-Weiss law with C = 0.723, 0.713, 0.712, and 0.342 K emu/mol and theta = -2.8, -3.1, -2.6, and +0.02 K, respectively, indicating that only the spins of the verdazyl radical cation contribute to the magnetic property of these salts. The salts 1, 3, and 5 are insulators. On the other hand, the conductivity (sigma) of the Ni salt 2 and Pd salt 4 at 20 degrees C was sigma = 8.9 x 10(-2) and 1.3 x 10(-4) S cm(-)(1) with an activation energy E(A) = 0.11 and 0.40 eV, respectively. The salts 2 and 4 are new molecular magnetic semiconductors.

Assignment of the in-plane molecular vibrations of the electron-donor molecule BDT-TTP based on polarized Raman and infrared spectra, in which BDT-TTP is 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene.

Infrared and Raman spectra of 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene (BDT-TTP) and 1,3,4,6-tetrathiapentalene-2,5-dione (TTP-DO) are reported. The vibrational modes of TTP-DO are assigned with the aid of the depolarization ratio of solution Raman spectra, polarized reflection spectra and polarized Raman spectra. A D2h symmetry is assumed for the BDT-TTP molecule and its in-plane fundamental vibrations are assigned with the aid of the polarization ratio and the correlation with TTP-DO, tetrathiafulvalene (TTF), tetramethyltetrathiafulvalene (TMTTF) and bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF). Normal coordinate calculation with a modified internal valence force field was carried out for the in-plane fundamental vibrations of TTP-DO and BDT-TTP. Ab initio calculations of the normal modes of BDT-TTP0 and BDT-TTP+ are compared with the empirical analysis.

Peroxisome proliferator-activated receptor-gamma haploinsufficiency enhances B cell proliferative responses and exacerbates experimentally induced arthritis.

Peroxisome proliferator-activated receptor-gamma (PPAR gamma) controls adipogenesis and glucose metabolism. It was reported recently that PPAR gamma activation by its agonistic ligands modifies lymphocyte function. Since synthetic ligands are known to exert their effect via PPAR gamma-dependent and -independent pathways, we examined the physiological role of PPAR gamma in lymphocytes by using heterozygote mutant mice in which one allele of PPAR gamma is deleted (PPAR gamma(+/-)). In contrast to T cells, which did not exhibit a significant difference, B cells from PPAR gamma(+/-) showed an enhanced proliferative response to stimulation by either lipopolysaccharide or cross-linking of antigen receptors. Dysregulation of the NF-kappa B pathway in B cells from PPAR gamma(+/-) was indicated by spontaneous NF-kappa B activation, as well as increased I kappa B alpha phosphorylation and gel-shift activity following LPS stimulation. Mice primed with either ovalbumin or methylated BSA also showed enhanced antigen-specific immune response of both T and B cells, an immunological abnormality that exacerbated antigen-induced arthritis. These findings indicate that PPAR gamma plays a critical role in the control of B cell response and imply a role in diseases in which B cell hyperreactivity is involved, such as arthritis and autoimmunity.

[Mechanism of autoantibody production].

Autoantibody is a hallmark of autoimmune diseases. In systemic autoimmune diseases such as systemic lupus erythematosus, the target of autoantibodies are mostly nuclear autoantigens like nucleosome and U1RNP. Since immune system comprise autoreactivity to develop itself, the chance of autoantibody appearance should not be rare. Therefore, the disturbance of immunoregulation for nuclear autoantigens might allow the persistence of autoantibody production. The studies of tolerance of nuclear antigens is required to understand autoimmune diseases and to develop more advanced immunotherapy.

Gene-transferred oligoclonal T cells predominantly persist in peripheral blood from an adenosine deaminase-deficient patient during gene therapy.

Adenosine deaminase (ADA) deficiency is the primary cause of severe combined immunodeficiency disease and has become a focus for developing innovative approaches to gene therapy. We previously described successful treatment of a Japanese ADA-deficient patient by periodic infusions of genetically modified autologous T lymphocytes transduced with a retroviral vector containing human ADA cDNA. In order to investigate whether polyclonality was restored by the gene therapy and whether the gene-transduced T lymphocytes persisted in the peripheral blood of the patient, we analyzed the T cell clonotype using a T cell receptor-specific RT-PCR/SSCP method. Oligoclonal T cell expansion was observed in every Vbeta family, and the expanded T cell clones were stable throughout the periodic gene therapy. Some of these T cell clones are likely carrying the vector, since they were identical to the clones selected by G418 resistance. Therefore, although it is uncertain when oligoclonal T cells started to expand and what percentage of the oligoclones carries the vector, the peripheral blood of the patient administered the gene therapy included oligoclonal T cells, some of which were identical to the ADA-gene-transduced clones.

Supernatant protein factor, which stimulates the conversion of squalene to lanosterol, is a cytosolic squalene transfer protein and enhances cholesterol biosynthesis.

Squalene epoxidase, a membrane-associated enzyme that converts squalene to squalene 2,3-oxide, plays an important role in the maintenance of cholesterol homeostasis. In 1957, Bloch and colleagues identified a factor from rat liver cytosol termed "supernatant protein factor (SPF)," which promotes the squalene epoxidation catalyzed by rat liver microsomes with oxygen, NADPH, FAD, and phospholipid [Tchen, T. T. & Bloch, K. (1957) J. Biol. Chem. 226, 921-930]. Although purification of SPF by 11,000-fold was reported, no information is so far available on the primary structure or biological function of SPF. Here we report the cDNA cloning and expression of SPF from rat and human. The encoded protein of 403 amino acids belongs to a family of cytosolic lipid-binding/transfer proteins such as alpha-tocopherol transfer protein, cellular retinal binding protein, yeast phosphatidylinositol transfer protein (Sec14p), and squid retinal binding protein. Recombinant SPF produced in Escherichia coli enhances microsomal squalene epoxidase activity and promotes intermembrane transfer of squalene in vitro. SPF mRNA is expressed abundantly in the liver and small intestine, both of which are important sites of cholesterol biosynthesis. SPF is expressed significantly in isolated hepatocytes, but the expression level was markedly decreased after 48 h of in vitro culture. Moreover, SPF was not detectable in most of the cell lines tested, including HepG2 and McARH7777 hepatomas. Transfection of SPF cDNA in McARH7777 significantly stimulated de novo cholesterol biosynthesis. These data suggest that SPF is a cytosolic squalene transfer protein capable of regulating cholesterol biosynthesis.

Antigen-specific T cells transduced with IL-10 ameliorate experimentally induced arthritis without impairing the systemic immune response to the antigen.

For the treatment of rheumatoid arthritis, efficient drug delivery methods to the inflamed joints need to be developed. Because T cells expressing an appropriate autoantigen-specific receptor can migrate to inflamed lesions, it has been reasoned that they can be employed to deliver therapeutic agents. To examine the ability and efficiency of such T cells as a vehicle, we employed an experimentally induced model of arthritis. Splenic T cells from DO11.10 TCR transgenic mice specific for OVA were transduced with murine IL-10. Adoptive transfer of the IL-10-transduced DO11.10 splenocytes ameliorated OVA-induced arthritis despite the presence of around 95% nontransduced cells. Using green fluorescent protein as a marker for selection, the number of transferred cells needed to ameliorate the disease was able to be reduced to 10(4). Preferential accumulation of the transferred T cells was observed in the inflamed joint, and the improvement in the disease was not accompanied by impairment of the systemic immune response to the Ag, suggesting that the transferred T cells exert their anti-inflammatory task locally, mainly in the joints where the Ag exists. In addition, IL-10-transduced DO11.10 T cells ameliorated methylated BSA-induced arthritis when the arthritic joint was coinjected with OVA in addition to methylated BSA. These results suggest that T cells specific for a joint-specific Ag would be useful as a therapeutic vehicle in rheumatoid arthritis for which the arthritic autoantigen is still unknown.

Diffuse intervertebral disk calcification in a patient with rheumatoid arthritis.

A patient with seronegative rheumatoid arthritis (RA) who presented with intervertebral disk calcification (IDC) of several thoracic and lumbar intervertebral disks in herein described. There was no evidence of any other coexisting diseases such as ochronosis and hemochromatosis, but a remarkable degree of polyclonal hypergammaglobulinemia was observed as a notable finding. Although the appearance of IDC on T1-weighted images on magnetic resonance is controversial, no increased signal intensity was observed in our patient. To the best of our knowledge, this is the first report of IDC in RA.

Functional reconstitution of class II MHC-restricted T cell immunity mediated by retroviral transfer of the alpha beta TCR complex.

Transfer of the alphabeta TCR genes into T lymphocytes will provide a means to enhance Ag-specific immunity by increasing the frequency of tumor- or pathogen-specific T lymphocytes. We generated an efficient alphabeta TCR gene transfer system using two independent monocistronic retrovirus vectors harboring either of the class II MHC-restricted alpha or beta TCR genes specific for chicken OVA. The system enabled us to express the clonotypic TCR in 44% of the CD4+ T cells. The transduced cells showed a remarkable response to OVA323-339 peptide in the in vitro culture system, and the response to the Ag was comparable with those of the T lymphocytes derived from transgenic mice harboring OVA-specific TCR. Adoptive transfer of the TCR-transduced cells in mice induced the Ag-specific delayed-type hypersensitivity in response to OVA323-339 challenge. These results indicate that alphabeta TCR gene transfer into peripheral T lymphocytes can reconstitute Ag-specific immunity. We here propose that this method provides a basis for a new approach to manipulation of immune reactions and immunotherapy.

Regulation of human eotaxin generation by Th1-/Th2-derived cytokines.

BACKGROUND: Accumulating evidence indicates that eotaxin is the primary mediator of tissue eosinophilia. In the present study, we analyzed the mechanisms of eotaxin generation by Th1-/Th2-derived cytokines in vitro. METHODS: Human dermal fibroblasts, human umbilical vein endothelial cells and A549 human bronchial epithelial cell line cells were stimulated with TNF-alpha, IL-4, IFN-gamma or TNF-alpha in combination with IL-4 or IFN-gamma and the amount of eotaxin production was analyzed. RESULTS: Fibroblasts produced nanogram/milliliter quantities of eotaxin. Proinflammatory cytokine TNF-alpha and Th2-type cytokine IL-4 each induced eotaxin production, and combination of them caused a marked synergistic increase in that production. On the other hand, Th1-type cytokine IFN-gamma inhibited eotaxin generation at the protein/mRNA levels. CONCLUSION: The Th2-derived cytokine upregulated while the Th1-derived cytokine inhibited eotaxin production by fibroblasts. In view of the Th1/Th2 paradigm, these results indicate that (1) eotaxin regulates eosinophil accumulation in the Th2-dominant state such as allergic disease, and (2) direct suppression of eotaxin production by IFN-gamma is one of the major mechanisms by which IFN-gamma suppresses eosinophilic inflammation.

[Antigen-specific T cells transduced with interleukin-10 ameliorate experimentally induced arthritis without impairing the systemic immune response to the antigen].

For the treatment of rheumatoid arthritis, efficient drug delivery methods to the inflamed joints need to be developed. Since T cells expressing an appropriate autoantigen-specific receptor can migrate to inflamed lesions, it has been reasoned that they can be employed to deliver therapeutic agents. In order to examine the ability and efficiency of such T cells as a vehicle, we employed an experimentally induced model of arthritis. Splenic T cells from DO 11.10 T cell receptor transgenic mice specific for OVA were transduced with murine IL-10. Adoptive transfer of the IL-10-transduced DO 11.10 splenocytes ameliorated OVA-induced arthritis, in spite of the presence of around 95% non-transduced cells. Using GFP as a marker for selection, the number of transferred cells needed to ameliorate the disease was able to be reduced to 10(4). Preferential accumulation of the transferred T cells was observed in the inflamed joint, and the improvement in the disease was not accompanied by impairment of the systemic immune response to the antigen, suggesting that the transferred T cells exert their antiinflammatory task locally, mainly in the joints where the antigen exists. In addition, IL-10-transduced DO 11.10 T cells ameriolated mBSA-induced arthritis when the arthritic joint was co-injected with OVA in addition to mBSA. These results suggest that T cells specific for a joint specific antigen would be useful as a therapeutic vehicle in rheumatoid arthritis for which the arthritic autoantigen is still unknown.

Dermal fibroblasts represent a potent major source of human eotaxin: In vitro production and cytokine-mediated regulation.

Accumulating evidence indicates that eotaxin plays an integral role in tissue recruitment of eosinophils in humans as well as in animals. To clarify which types of cells are actually important as sources of human eotaxin, we used a specific enzyme-linked immunosorbent assay (ELISA) to compare various types of hemopoietic and nonhemopoietic cells for the ability to produce eotaxin protein. Regardless of various conditioning, we failed to determine any significant eotaxin generation by peripheral leukocytes and vein endothelial cells (less than 20 pg/ml). A small amount of immunoreactive eotaxin was detected in cultures of A549 bronchial epithelial cell line cells. In contrast, dermal fibroblasts were capable of generating extremely high, and potentially biologically relevant, amounts of eotaxin protein (on the order of ng/ml). The eotaxin generation was induced by tumour necrosis factor alpha (TNF-alpha) or IL-4, and the production was drastically increased by combined use of these cytokines. Because fibroblasts are ideally situated within the interstium at the sites of allergic responses, our finding that these cells represent an important cellular source of eotaxin suggests that fibroblast-derived eotaxin may act to regulate eosinophil recruitment in a paracrine fashion.

[Immunological tolerance and autoimmune disease].

The immune system must remain tolerant to self-antigens so as not to destroy what it has evolved to protect. There appears several mechanism for this purpose; deletion, anergy, sequestration of autoantigen and active suppression. These mechanism cooperate, constituting a fail-safe system, although the strategy against each autoantigen is determined by the nature of the autoantigen, i.e., the amount, timing and location of the expression. Here, we review and discuss on the pathogenesis of autoimmune disease as a consequence of the breakdown of the surveillance network, based on the recent advances in immunology.

Altered expression level of a systemic nuclear autoantigen determines the fate of immune response to self.

One of the hallmarks of systemic autoimmune diseases is immune responses to systemic nuclear autoantigens. We have examined the fate of the immune response against a nuclear autoantigen using human U1 small nuclear ribonucleoprotein-A protein (HuA) transgenic (Tg) mice by adoptive transfer of autoreactive lymphocytes. We obtained two Tg lines that have different expression levels of the transgene. After spleen cells from HuA-immunized wild-type mice were transferred to Tg mice and their non-Tg littermates, these recipients were injected with HuA/IFA to induce a recall memory response. HAB69, which expressed a lower amount of HuA, exhibited a vigorous increase in the autoantibody level and glomerulonephritis. Moreover, the autoreactivity spread to 70K autoantigen. Alternatively, in HAB64, which expressed a higher amount of HuA, the production of autoantibody was markedly suppressed. The immune response to HuA autoantigen was impaired as demonstrated in a both delayed-type hypersensitivity response and proliferation assay. This inhibition was Ag-specific and was mediated by T cells. These data suggest that the expression level of systemic autoantigens influences the outcome of the immune response to self.