Circulating IgA and IgE autoantibodies in antilaminin-332 mucous membrane pemphigoid

BACKGROUND

Antilaminin-332 mucous membrane pemphigoid (MMP) is a chronic autoimmune bullous disease that is often associated with internal malignancy. IgG autoantibodies against laminin-332 in patients with MMP are well documented; however, IgA and IgE autoantibodies against laminin-332 have not yet been described.

OBJECTIVES

To characterize IgA and IgE autoantibodies binding to laminin-332 in sera from patients with antilaminin-332 MMP.

METHODS

Sera and skin samples from four patients who met the following criteria were used: (i) subepidermal blistering lesions present on the mucous membranes; (ii) in vivo deposition of IgG along the epidermal basement membrane zone of sampled skin; (iii) circulating IgG antibasement membrane zone antibodies that react with the dermal side of salt-split normal human skin; and (iv) circulating IgG autoantibodies that do not show positivity against type VII collagen or 200-kDa protein (p200 antigen) in immunoblot analysis using dermal extracts. Circulating IgG/IgA/IgE class autoantibodies against laminin-332 were determined by immunoblotting.

RESULTS

Circulating IgG autoantibodies against the gamma2, alpha3/gamma2, alpha3 and alpha3/beta3/gamma2 subunits of laminin-332 were demonstrated in sera from four patients, respectively. Serum from one of the four patients showed IgA reactivity with the alpha3/beta3/gamma2 subunits of laminin-332. Serum from one of the four patients showed IgE reactivity with the gamma2 subunit of laminin-332. The control sera failed to display IgG/IgA/IgE reactivity to laminin-332.

CONCLUSIONS

In addition to IgG autoantibodies, circulating IgA and IgE autoantibodies against laminin-332 are detectable in a subset of patients with antilaminin-332 MMP.

HTLV-1 proviruses encoding non-functional TAX in adult T-cell leukemia

Adult T-cell leukemia (ATL) is associated with prior infection with human T-cell leukemia virus type 1 (HTLV-1). TAX, the major transactivator of HTLV-1, has been implicated in the immortalization of infected T-cells, but molecular mechanisms of in vivo malignant cell transformation induced by HTLV-1 remain unclear. To investigate the role of TAX in the monoclonal proliferation of ATL cells, we determined the nucleotide sequence of tax DNA clones obtained from 6 ATL patients and analysed the biological function of their products. We found that ATL cells from 2 of these patients possessed tax with a nonsense or frame-shift mutation resulting in the premature termination of its protein product, which was no longer functional. This strongly argued against an indispensable role of TAX for the maintenance of ATL cells in vivo. On the other hand, the frequency of nucleotide substitutions found in non-functional tax DNA clones from these patients was significantly lower than those in functional tax DNA clones from the others, suggesting a role for TAX in the genome instability of infected cells. Although mismatch repair defects in the microsatellite markers, including those in hMSH3, hMSH6, BAX, TGF-beta RII, and E2F4 genes, were infrequent, we found an increase in the number of CAG repeats of the E2F4 microsatellite marker in 1 patient. These findings indicate that while TAX may be a necessary prerequisite for malignant transformation of infected cells, it is not essential for the maintenance of ATL cells in vivo.

Identification of genes associated with the progression of adult T cell leukemia (ATL)

Patients with adult T-cell leukemia/lymphoma (ATL) exhibit a variety of clinical features, and this disease is therefore clinically subclassified into acute, lymphomatous, chronic, and smoldering types. Acute ATL is a typical leukemic form of ATL with rapid progression, and chronic ATL is a less aggressive clinical form allowing long-term survival even without chemotherapy. In the present study, we used fresh peripheral blood mononuclear cells (PBMC) from both types of ATL patients to identify molecules that may contribute to the difference between acute and chronic ATL. Isolated mRNAs expressed differentially between the two types of ATL include a T-cell differentiation antigen (MAL), a lymphoid-specific member of the G-protein-coupled receptor family (EBI-1 / CCR7), a novel human homologue to a subunit (MNLL) of the bovine ubiquinone oxidoreductase complex, and a human fibrinogen-like protein (hpT49). We found that the former three are upregulated in acute ATL and the last is down-regulated in both chronic and acute ATL. We speculate that dysregulation of the genes may account for the malignant features of ATL cells, in terms of growth, energy metabolism, and motility.

Comparative molecular analysis of HTLV-I proviral DNA in HTLV-I infected members of a family with a discordant HTLV-I-associated myelopathy in monozygotic twins

In order to elucidate the underlying mechanisms of a discordant case with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) in monozygotic twins, we investigated HTLV-I tax sequences of 10 - 18 polymerase chain reaction-based clones each derived from peripheral blood mononuclear cells of the twins as well as their infected mother and an elder brother who also suffered from HAM/TSP. Sequence comparison revealed that three of the infected individuals including a twin with HAM/TSP shared the consensus tax sequence identical to the reference, ATK-1, but that of another healthy twin was different at five nucleotide positions including three nonsynonymous changes from ATK-1. This finding strongly suggested that different HTLV-I strains infected the monozygotic twins and the difference in infected proviral sequences determined the discordant clinical outcomes. Transfection and subsequent reporter assays failed to show a significant difference in transactivation activity on HTLV-I LTR and NF-kappaB elements between the products of the two sequences. Two HAM/TSP patients (a twin and elder brother) among three members infected with the ATK-1 type virus shared a paternal HLA allele which was absent in the healthy individual (mother). Genetic analysis of sequence variation in the tax sequences of the discordant twins showed that the Dn/Ds ratio was high in the healthy twin but low in the twin with HAM/TSP, implying the presence of more intense selection forces in the carrier. Our findings strongly suggested that a particular combination of HTLV-I strains with an HLA genotype would be a risk for HAM/TSP.

Up-regulation of human T lymphotropic virus type 1 (HTLV-1) tax/rex mRNA in infected lung tissues

HTLV-1 has been implicated in certain pulmonary diseases. We previously demonstrated that expression of HTLV-1 tax/rex mRNA, encoding the transcriptional transactivator Tax, was closely associated with infiltration of activated T lymphocytes into lung tissue. To explore mechanisms of tax/rex expression in the lung, tax/rex mRNA expression and proviral DNA load were compared between peripheral blood mononuclear cells (PBMC) and bronchoalveolar lavage cells (BALC) from four patients with HTLV-1-associated myelopathy (HAM/TSP) and 13 carriers with various pulmonary symptoms. Semiquantitative detection of tax/rex mRNA strongly suggested that the lung was a preferential site for its expression. Proviral DNA loads in non-HAM/TSP carriers were variable but correlated well between PBMC and BALC in each individual, and revealed no relationship with tax/rex mRNA expression. In contrast, both cell groups from four HAM/TSP patients expressed detectable tax/rex mRNA accompanied by high proviral DNA load. The ratio of tax/rex mRNA expression to proviral DNA load was higher in BALC than in PBMC in three of four carriers and in three of four HAM/TSP patients, suggesting up-regulation of tax/rex mRNA in infected lung tissue. To analyse differences in distribution of HTLV-1 quasispecies between the two tissues, phylogenetic analysis was performed for sequence sets of the proviral tax open reading frame (ORF: 1059 bp) derived from PBMC and BALC of two infected individuals. Sequences derived from the two tissues distributed similarly to branches of phylogenetic trees, and there was no evidence of selective distribution of certain quasispecies in the lung. Our results suggest the presence of tissue-specific conditions that activate viral expression in infected cells in the lung. Constitutive exposure of this tissue to foreign antigens leading to up-regulation of basal viral promoter activity is likely to be one such mechanism.

Demographic and reproductive factors for high seroprevalence of Chlamydia trachomatis among pregnant women in Japan

In order to elucidate demographic and reproductive factors associated with Chlamydia trachomatis seropositivity, serological screening and questionnaire survey were conducted on pregnant women in Nagasaki Prefecture, Japan. Serum samples were taken from 1718 pregnant women between September and December, 1996, at the cooperative obstetric hospitals and clinics, and tested for the presence of antibodies to C. trachomatis using the enzyme immunoassay. A questionnaire was administered on a sub-sample (n -409), among whom 85 (20.8%) were seropositive. A multiple logistic analysis revealed that four characteristics showed a significant association with the seropositivity: (i) experience of premarital pregnancy, (ii) non use of condoms, (iii) short duration of education, and (iv) more frequent induced abortion. The unsafe sexual behavior of young people lacking proper knowledge of how to prevent STD is the most important intervention target for control of the C. trachomatis epidemic in Japan.

Upregulation of the genes encoding lysosomal hydrolases, a perforin-like protein, and peroxidases in the brains of mice affected with an experimental prion disease

In an attempt to identify the molecules involved in the pathogenesis of prion diseases, we performed cDNA subtraction on the brain tissues of mice affected with an experimental prion disease and the unaffected control. The genes identified as being upregulated in the prion-affected brain tissue included those encoding a series of lysosomal hydrolases (lysozyme M and both isoforms of beta-N-acetylhexosaminidase), a perforin-like protein (macrophage proliferation-specific gene-1 [MPS-1]), and an oxygen radical scavenger (peroxiredoxin). Dramatic increases in the expression level occurred at between 12 and 16 weeks after intracerebral inoculation of the prion, coinciding with the onset of spongiform degeneration. The proteinase K-resistant prion protein (PrP(Sc)) became detectable by immunoblotting well before 12 weeks, suggesting a causal relationship between this and the gene activation. Immunohistochemistry paired with in situ hybridization on sections of the affected brain tissue revealed that expression of the peroxiredoxin gene was detectable only in astrocytes and was noted throughout the affected brain tissue. On the other hand, the genes for the lysosomal hydrolases and MPS-1 were overexpressed exclusively by microglia, which colocalized with the spongiform morphological changes. A crucial role for microglia in the spongiform degeneration by their production of neurotoxic substances, and possibly via the aberrant activation of the lysosomal system, would have to be considered.

Fas gene mutation in the progression of adult T cell leukemia

Fas antigen (Apo-1/CD95) is an apoptosis-signaling cell surface receptor belonging to the tumor necrosis factor receptor superfamily. Adult T cell leukemia (ATL) cells express Fas antigen and show apoptosis after treatment with an anti-Fas monoclonal antibody. We established the ATL cell line KOB, which showed resistance to Fas-mediated apoptosis, and found that KOB expressed two forms of Fas mRNA, the normal form and a truncated form. The truncated transcript lacked 20 base pairs at exon 9, resulting in a frame shift and the generation of a premature stop codon at amino acid 239. The same mutation was detected in primary ascitic cells and peripheral blood cells. The mutation was not detected in lymph node cells, however, although all of the primary ATL cells were of the same clonal origin. A retroviral-mediated gene transfer of the truncated Fas to Jurkat cells rendered the cells resistant to Fas-mediated apoptosis, suggesting a dominant negative interference mechanism. These results indicate that an ATL subclone acquires a Fas mutation in the lymph nodes, enabling the subclone to escape from apoptosis mediated by the Fas/Fas ligand system and proliferate in the body. Mutation of the Fas gene may be one of the mechanisms underlying the progression of ATL.

Low copy numbers of human T-cell lymphotropic virus type I (HTLV-I) tax-like DNA detected in the salivary gland of seronegative patients with Sjögren's syndrome in an HTLV-I endemic area

To evaluate the hypothesis, proposed in previous reports from HTLV-I non-endemic areas, that HTLV-I is involved in a significant proportion, about a quarter, of Sjögren's syndrome patients who lack serum antibodies to the virus, we examined for the presence or absence of HTLV-I in DNA samples isolated from salivary gland tissues of 17 seronegative as well as 7 seropositive patients with Sjögren's syndrome in Nagasaki, Japan, where the virus is highly endemic. The nested two-step polymerase chain reaction (PCR), with a sensitivity capable of detecting a single DNA molecule, failed to amplify the HTLV-I tax sequence from DNA of 14 of the 17 seronegative patients. The tax was only amplifiable from the tissue DNA of the remaining three seronegative patients. The detection rate, 3/17 (18%), was, unexpectedly, less than those previously reported from the HTLV-I non-endemic areas. Moreover, in contrast to high viral loads (10(-1) to 10(-3) per cell) in the salivary gland of the seropositive patients, a semiquantitative PCR revealed that the copy number of the HTLV-I tax in the gland tissue of these seronegative patients was very low, 10(-5) per cell. This level is unlikely to be sufficient to promote an inflammatory reaction in the tissue. Our findings might argue against the involvement of "prototype" HTLV-I in the pathogenesis of Sjögren's syndrome in seronegative patients.

Impaired motor coordination in mice lacking prion protein

1. Prion protein (PrPC) is a host-encoded glycoprotein constitutively expressed on the neuronal cell surface. Accumulation of its protease-resistant isoform is closely related to pathologic changes and prion propagation in the brain tissue of a series of prion diseases. However, the physiological role of PrPC remains to be elucidated. 2. After long-term observation, we noted impaired motor coordination and loss of cerebellar Purkinje cells in the aged mice homozygous for a disrupted PrP gene, a finding which strongly suggests that PrPC plays a role in the long-term survival of Purkinje cells. 3. We also describe the resistance of the PrP null mice to the prion, indicating the requirement of PrPC for both the development of prion diseases and the prion propagation.

Molecular cloning and pharmacological characterization of an atypical gerbil angiotensin II type-1 receptor and its mRNA expression in brain and peripheral tissues

In the gerbil brain, most of the [125I]Sarcosine1-Angiotensin II binding sites are atypical, not sensitive to displacement with selective Angiotensin II AT1 and AT2 receptor ligands. A similar atypical binding profile exists in the gerbil kidney, where binding is highly expressed. We isolated a 2197 base pair clone from a gerbil kidney cDNA library which encodes a 359 amino acid protein with higher than 90% homology to other mammalian angiotensin II AT1 receptors. When expressed in COS-7 cells, stimulation by Angiotensin II of both the cloned gerbil receptor or the human AT1 receptor enhanced IP3 production to a similar degree. In COS-7 cells, the gerbil receptor also had a ligand affinity profile similar to that of the human AT1 receptor, but showed greatly reduced affinity for losartan (IC50=3480+/-174 nM). In the gerbil brain, in situ hybridization revealed receptor mRNA in circumventricular organs, selective hypothalamic, midbrain and brain stem areas, and in the hippocampus, where high mRNA expression was detected in the stratum pyramidale of the CA1 and CA2 subfields, and in the stratum granulosum of the dentate gyrus. The expression pattern of receptor mRNA corresponded well with that of atypical [125I]Sar1-Ang II binding. In situ hybridization and Southern blot experiments using riboprobes against the open reading frame and the 3'-untranslated region of the cloned gerbil Ang II receptor cDNA suggest that gerbils have, like other rodents, two AT1 receptor subtypes. The receptor mRNA distribution of the cloned gerbil Ang II receptor corresponds to the distribution of AT1A receptors described in other rodent species.

Interleukin-15 (IL-15) can replace the IL-2 signal in IL-2-dependent adult T-cell leukemia (ATL) cell lines: expression of IL-15 receptor alpha on ATL cells

Interleukin-15 receptor (IL-15R) and IL-2R have the same beta and gamma chains, but IL-15R has a specific alpha chain distinct from that of IL-2Ralpha, which is indispensable for the high affinity binding of IL-15. In the present study, we examined four IL-2-dependent adult T-cell leukemia (ATL) cell lines for their IL-15R expression. All cell lines bound IL-15, which was not inhibited by a 100-fold excess amount of IL-2, proliferated in response to IL-15 to the same degree as to the stimulation with IL-2, and were maintained without IL-2. The responses to 1L-15 were inhibited by the antibodies against IL-2R beta or gamma chains but was not by the IL-2R alpha chain antibody. [125I]-IL-15 exhibited a single high-affinity binding with an apparent kd of 0.17 nmol/L. Reverse transcription-coupled polymerase chain reaction (RT-PCR) showed that the cell lines had the mRNA of IL-15R alpha. The cell lines also had IL-15 mRNA. Despite the presence of IL-15 mRNA, the cell lines did not secrete IL-15, and the culture supernatants of fresh ATL cells and plasma from the patients did not contain a detectable amount of IL-15 with a few exceptional cases, although fresh ATL cells also responded to IL-15. These results suggest that ATL cells have the complete form of IL-15R and respond to IL-15. Such an IL-15-dependent cell proliferation mechanism might be used in the development of ATL and for the invasion and proliferation of ATL cells in the visceral organs.

Loss of cerebellar Purkinje cells in aged mice homozygous for a disrupted PrP gene

Prion protein (PrP) is a glycoprotein constitutively expressed on the neuronal cell surface. A protease-resistant isoform of prion protein is implicated in the pathogenesis of a series of transmissible spongiform encephalopathies. We have developed a line of mice homozygous for a disrupted PrP gene in which the whole PrP-coding sequence is replaced by a drug-resistant gene. In keeping with previous results, we find that homozygous loss of the PrP gene has no deleterious effect on the development of these mice and renders them resistant to prion. The PrP-null mice grew normally after birth, but at about 70 weeks of age all began to show progressive symptoms of ataxia. Impaired motor coordination in these ataxic mice was evident in a rotorod test. Pathological examination revealed an extensive loss of Purkinje cells in the vast majority of cerebellar folia, suggesting that PrP plays a role in the long-term survival of Purkinje neurons.

Activity of Fgr protein-tyrosine kinase is reduced in neutrophils of patients with myelodysplastic syndromes and chronic myelogenous leukemia

The Fgr protein-tyrosine kinase, p55(c-fgr), is specifically expressed and functions in cells of myelomonocytic lineages. We examined levels of expression and enzymatic activity of p55(c-fgr) peripheral blood neutrophils of patients with myelodysplastic syndromes (MDS) and chronic myelogenous leukemia (CML) by comparison with those of normal individuals. While neutrophils of eight normal subjects gave uniform results, the specific enzymatic activity of p55(c-fgr), a ratio of the total kinase activity versus the protein level was reduced in seven out of eight patients with MDS and all of five patients with CML. The specific kinase activity of p55(c-fgr) correlated significantly with the activity of neutrophil alkaline phosphatase (NAP) which has been considered to be a marker of neutrophil maturity (r=0.568, P<0.01). The reduced activity of this tyrosine kinase was considered to be a biological parameter for immaturity and to reflect dysfunction of neutrophils of patients with MDS and with CML.

Two subtypes of endothelin receptors and endothelin peptides are expressed in differential cell types of the rat placenta: in vitro receptor autoradiographic and in situ hybridization studies

We studied the localization of endothelin (ET) receptors and ET peptides in the rat placenta. In vitro receptor autoradiographic and in situ hybridization studies revealed the differential and cell-specific distribution of ET receptor subtypes, suggesting that each ET receptor plays a different role in the function of the placenta. The expression of the ETB receptor was concentrated to cytotrophoblasts and trophoblastic giant cells of the basal zone, in which fetal cells directly face maternal cells. The ETA receptor was confined to the decidual tissue and vascular wall. Both ET receptors coexisted in the labyrinth in an approximately 50:50 ratio. Prepro-ET-1 messenger RNA (mRNA) was detected in cytotrophoblasts and trophoblastic giant cells of the basal zone and endothelial cells of vessels, whereas ET-1-like immunoreactivity was present not only in trophoblasts and endothelial cells, but also in the decidual tissue and vascular wall. ET-3 mRNA was localized in migrating cells. We also found changes in the expression levels of ET receptors by means of a cold ligand saturation study. The number of specific [125I]ET-1-binding sites was increased in the basal zone and labyrinth with gestation, but not in the decidual tissue. The enhancement of ETA receptor, ETB receptor, and prepro-ET-1 mRNA levels was also supposed, based on data obtained by RT-PCR Southern hybridization. On the other hand, ET-3 mRNA levels were reduced with gestation. These findings support the idea that ETs, through interaction with ETA and ETB receptors, play an important role in the regulation of placental growth and fetoplacental circulation through autocrine and paracrine mechanisms.

Accumulation of proteinase K-resistant prion protein (PrP) is restricted by the expression level of normal PrP in mice inoculated with a mouse-adapted strain of the Creutzfeldt-Jakob disease agent

Creutzfeldt-Jakob disease (CJD) is a transmissible neurodegenerative disease of humans caused by an unidentified infectious agent, the prion. To determine whether there was an involvement of the host-encoded prion protein (PrPc) in CJD development and prion propagation, mice heterozygous (PrP+/-) or homozygous (PrP-/-) for a disrupted PrP gene were established and inoculated with the mouse-adapted CJD agent. In keeping with findings of previous studies using other lines of PrP-less mice inoculated with scrapie agents, no PrP-/- mice showed any sign of the disease for 460 days after inoculation, while all of the PrP+/- and control PrP+/+ mice developed CJD-like symptoms and died. The incubation period for PrP+/- mice, 259 +/- 27 days, was much longer than that for PrP+/+ mice, 138 +/- 12 days. Propagation of the prion was barely detectable in the brains of PrP-/- mice and was estimated to be at a level at least 4 orders of magnitude lower than that in PrP+/+ mice. These findings indicate that PrPc is necessary for both the development of the disease and propagation of the prion in the inoculated mice. The proteinase-resistant PrP (PrPres) was undetectable in the brain tissues of the inoculated PrP-/- mice, while it accumulated in the affected brains of PrP+/+ and PrP+/- mice. Interestingly, the maximum level of PrPres in the brains of PrP+/- mice was about half of the level in the similarly affected brains of PrP+/+ mice, indicating that PrPres accumulation is restricted by the level of PrPc.

Inhibitory activity in saliva of cell-to-cell transmission of human T-cell lymphotropic virus type 1 in vitro: evaluation of saliva as an alternative source of transmission

Human T-cell lymphotropic virus type 1 (HTLV-1) is known to be transmitted vertically through breastfeeding and horizontally by blood transfusion and sexual contact. Our intervention study has suggested the presence of additional alternative maternal transmission pathways. To explore the possibility of transmission through saliva, we used PCR to quantify the HTLV-1 provirus in saliva samples from 18 carrier mothers and 10 patients with HTLV-1-associated myelopathy/tropical spastic paraparesis. The provirus was detected in 60 and 90%, respectively, of the samples, with estimated copy numbers in the range of 10 to 10(4)/ml. However, the saliva, regardless of the presence or absence of antibodies to the virus, showed a strong tendency to inhibit the cell-to-cell transmission of HTLV-1 in vitro, as examined by a syncytium inhibition assay. The natural inhibitory activity in saliva of seronegative volunteers was heat sensitive, and most of the activity was recovered by ultrafiltration in the fraction of macromolecules with a molecular weight of more than 100,000. In addition to this natural activity, saliva of HTLV-1-infected individuals contained immunoglobulin G molecules capable of neutralizing syncytium formation. These results strongly suggested that HTLV-1-infected cells in the carriers' saliva, which contains neutralizing antibodies in addition to the natural activity inhibiting cell-to-cell viral infection, barely transmit the virus. Transmission of HTLV-1 through the saliva would thus seem to be rare, if it occurs at all.

[Effectiveness of haloperidol in the treatment of chorea minor]

Chorea minor is the most curious manifestation of rheumatic fever, first described by Sydenham in 1686. Subsequent evidence showed that chorea could be a late manifestation of rheumatic fever, often occurring several months after a streptococcal infection in contrast to other major manifestations. During the ten-year period between 1984 and 1993, 11 children with rheumatic fever were seen at our hospital, two cases of these being accompanied with chorea minor. Case 1, a male aged 12, presented with involuntary movements. He was diagnosed as having rheumatic fever because of chorea and systolic ejection murmur at the apex of the heart. Plain cranial CT was normal. However, positron emission computed tomography revealed an increased 11C-glucose uptake in the caudate nucleus as compared with the cerebral cortex. Case 2, a female aged 14, presented with involuntary movements. Plain cranial CT was normal, but single photon emission CT showed a difference between the right and left brain. These two patients were given penicillin G (PCG), predonisolone (PSL) and haloperidol. Haloperidol was administered, because PCG and PSL had no effect to improve the clinical manifestations. After administer decreased to a half with a clinical improvement, but the level of GABA did not change. Haloperidol seemed to be an effective and useful agent for motor manifestations of the disease.

Autoantibodies against glutamic acid decarboxylase 65 in Japanese patients with insulin-dependent diabetes mellitus (IDDM)

Glutamic acid decarboxylase (GAD) 65 antibodies were measured by a new quantitative immunoprecipitation followed by immunoblotting assay using Chinese hamster ovary cells to produce recombinant human islet GAD65 and were compared with islet cell antibodies (ICA), antibodies against 64,000-Mr islet cell proteins (64K antibodies) and antibodies against GAD purified from pig brain. This assay showed that sensitivity and specificity were 83.3% and 100%, respectively. GAD65 antibodies were assayed in 32 Japanese patients with insulin-dependent diabetes mellitus (IDDM), 25 patients with non-insulin-dependent diabetes mellitus (NIDDM and 25 healthy volunteers. GAD65 antibodies were found in 12 (80.0%) of 15 patients with newly-diagnosed IDDM and in 9 (52.9%) of 17 patients with long-term IDDM. GAD65 antibodies were detected in none of 25 patients with NIDDM or 25 healthy volunteers. The correlation between GAD65 antibodies and ICA, and 64K antibodies was observed to be significant (r = 0.60, P = 0.0003 and r = 0.47, P = 0.007, respectively). GAD65 antibodies and antibodies against GAD purified from pig brain correlated well (r = 0.70, P = 0.0001). The concordance between GAD65 antibodies and ICA, 64K antibodies, and antibodies against GAD purified from pig brain, including GAD65 and GAD67, were 87.5% (28/32), 75.0% (24/32) and 90.6% (29/32), respectively. We observed that a quantitative immunoprecipitation followed by immunoblotting assay had high sensitivity and specificity in detecting GAD65 antibodies, that the prevalence of GAD65 antibodies was as high as in Caucasians, and that GAD65 was also one of the major autoantigens in Japanese patients with IDDM.

Prevalence of serum and salivary antibodies to HTLV-1 in Sjögren's syndrome

There is accumulating evidence that human T-lymphotropic virus-1 (HTLV-1) infection contributes to the development of various inflammatory disorders. To elucidate the relation between the infection and Sjögren's syndrome, seroepidemiological and virological studies were conducted on patients with this syndrome in Nagasaki Prefecture, Japan, an area heavily endemic for HTLV-1. The HTLV-1 seroprevalence rate among the patients with Sjögren's syndrome (17/74, 23%) was significantly higher than that among blood donors (916/27,284, 3%), whereas the difference between patients with systemic lupus erythematosus and blood donors was insignificant. Moreover, among Sjögren's syndrome patients the seroprevalence was high irrespective of age, unlike that among blood donors, which rose with age. Titres of serum antibodies in the HTLV-1 seropositive patients with Sjögren's syndrome were similar to those among patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and significantly higher than those among healthy carriers. IgM class antibodies were commonly detected in the serum of patients with Sjögren's syndrome. However, unlike that in HAM/TSP patients, the viral load in peripheral-blood mononuclear cells was not necessarily high in the seropositive Sjögren syndrome group. Salivary IgA antibodies to HTLV-1 were common among seropositive patients with Sjögren's syndrome (5/7), which might be due to increased viral activity in the salivary glands. These antibodies were barely detectable in HAM/TSP patients (prevalence 1/10) or in healthy carriers (0/11). The findings strongly suggest that HTLV-1 is involved in the pathogenesis of the disease in a subset of patients with Sjögren's syndrome in endemic areas.

Altered expression of a novel cellular gene as a consequence of integration of human T cell lymphotropic virus type 1

By analysing a genomic DNA clone derived from the human T cell lymphotropic virus type 1 (HTLV-1)-infected cell line, TL-Su, we found that an integrated HTLV-1 provirus interrupted the poly(A) signal-containing exon of a novel gene, RY-1. Nucleotide sequence analysis of a cDNA derived from Jurkat cells revealed that the normal RY-1 mRNA could encode a novel protein that has an unique primary structure, suggesting that a nucleic acid binding property was involved. Proviral integration led to an accumulation of aberrant RY-1 mRNA species in the cells. All the aberrant RY-1 cDNAs derived from TL-Su cells terminated at the poly(A) site of the R region of the HTLV-1 long terminal repeat and initiated in the intron, approx. 800 bp upstream from the putative second exon. Furthermore, another intron, downstream from this position, remained unspliced in some of the cDNAs. In addition to the activation by the integrated viral elements of cryptic promoters located upstream, mechanisms involving altered rates of degradation or transport from the nucleus to the cytoplasm of intron-containing RNA were suggested.

Transactivation of the human interleukin-6 gene by human T-lymphotropic virus type 1 Tax protein

Interleukin-6 (IL-6) is a multifunctional cytokine that regulates both humoral and cellular immune responses. Accumulating evidence suggests that the infection of T cells and other cell types with human T-lymphotropic virus type 1 (HTLV-1) results in the constitutive expression of IL-6. However, the underlying molecular mechanisms are little understood. When a reporter plasmid, pIL6-CAT-E3, in which the human IL-6 enhancer/promoter region from -630 to +14 was linked to the bacterial chloramphenicol acetyltransferase (CAT) gene, was transfected, HTLV-1-infected but not -uninfected T-cell lines activated the IL-6 promoter. This indicated the presence of a factor transactivating the IL-6 gene in the infected cells. To evaluate the involvement of the HTLV-1-encoded transacting factor (Tax) in this transactivation, we examined the effect of transient cotransfection with the Tax-expression plasmid, pMAX-Neo, on the transcription from the IL-6 promoter by use of COS1 cells. The cotransfected COS1 has about six-times greater the CAT activity than that transfected with pIL6-CAT-E3 alone. The analysis of a series of deletions of the IL-6 promoter suggested that the region (-105/-47) containing a NF kappa B site was crucial for the Tax responsiveness. We further examined the effect of Tax on endogenous IL-6 gene expression using the Jurkat clone, JPX-9, stably transfected with pMAX-Neo. JPX-9 accumulated steady state transcripts of the endogenous IL-6 gene in response to the induction of Tax expression. Our findings indicate an important role of the Tax protein in the expression of IL-6 in cells infected with HTLV-1.

HTLV-I proviral DNA in umbilical cord blood of babies born to carrier mothers

Human T-lymphotropic virus type I (HTLV-I) in cord blood raises the possibility of intrauterine transmission as an alternative pathway to transmission via breast milk. However, none of 7 children with HTLV-I proviral DNA positive cord blood had seroconverted by 24-48 months. Contamination of cord blood by maternal blood was precluded on the basis of viral load and IgA concentration. Thus cord blood proviral DNA is not a hallmark of intrauterine infection. Moreover, none of the cord blood samples of 9 formula-fed children later confirmed to be infected was positive for HTLV-I, indicating that intrauterine infection is not a likely candidate as an alternative pathway.

Cloning of a complete protein-coding sequence of human platelet-type phosphofructokinase isozyme from pancreatic islet

We have cloned a full length protein-coding sequence of human platelet-type phosphofructokinase (PFK) from pancreatic islet cDNA library. The platelet-type PFK was composed of 784 amino acids and had a deduced molecular weight of 85,590. Homologies in the primary structure with muscle- and liver-type PFK were 71 and 67%. Clear similarities of the amino and carboxyl halves with a prokaryotic PFK indicated an evolutionary event that duplicated genes of a prototype PFK fused into larger genes of eukaryotic PFKs. Amino acid residues constituting the binding sites for various allosteric modulators were well conserved, while a couple of different residues at the inhibitory ATP sites among three isozymes may partly explain their varied degree of sensitivities to ATP. Considerable amount of platelet-type PFK expression was demonstrated in brain, heart, kidney, colon and testis.

Kinetics of infectivity are dissociated from PrP accumulation in salivary glands of Creutzfeldt-Jakob disease agent-inoculated mice

The protease-resistant isoform of prion protein (PrP) has been implicated in the pathogenesis and transmission of Creutzfeldt-Jakob disease (CJD), scrapie and other related diseases, but the relationship between the infectious agent and PrP awaits elucidation. In the present study, we have examined levels of infectivity together with accumulation of the protease-resistant form of PrP (PrPCJD) in various tissues of CJD agent-inoculated mice. Accumulation of PrPCJD occurred only in tissues, including brain, salivary gland and spleen, in which infectivity was readily detectable throughout the course of the experiment. The brain showed the highest levels of both infectivity and PrPCJD accumulation, with well correlated kinetics. On the other hand, the high titres of infectivity detected in salivary gland and spleen early after inoculation of the agent were obviously distinguishable from PrPCJD. Furthermore, in the salivary gland, the kinetics of infectivity and the accumulation of PrPCJD reversed; infectivity declined as PrPCJD accumulated in the tissue. Our findings indicate that PrPCJD accumulation is associated with replication of the agent; however, PrPCJD is unlikely to be the agent itself.

Clinical course of human T-lymphotropic virus type I carriers with molecularly detectable monoclonal proliferation of T lymphocytes: defining a low- and high-risk population

To characterize the prodromal phase of adult T-cell leukemia (ATL), a prospective follow-up study was conducted on 50 carriers in a putative pre-ATL state. This state was defined by the presence of molecularly-detectable monoclonal proliferation of human T-lymphotropic virus type I (HTLV-I)-infected T lymphocytes, and the absence of clinical symptoms of leukemia. The median observation time was 50 months. The pre-ATL subjects were divided into two groups according to initial white blood cell (WBC) counts: group A, those with a normal WBC count (9,000/microL) (n = 30), and group B, those with an increased WBC count (9,000 to 15,000) (n = 20). Comparisons were made between the two groups and with a group of 25 patients with chronic ATL (group C) who had WBC counts of more than 15,000. Significant differences in survival rate were found between groups A and B (10-year survival 65.7%) and group C (32.8%) (P < .01), and between group A (10-year survival 90.0%) and group B (52.1%) (P < .05). The incidence of transformation to overt ATL was 10% (3 of 30) in group A and 50% (10 of 20) in group B (P < .01). In six transformed cases (one in A and five in B) we found exactly the same integration sites in pre-ATL and overt ATL phases, confirming the multistep leukemogenesis hypothesized for this disease. However, the pre-ATL subjects could be divided into two distinct prognostic groups based on the initial WBC count; those with good and those with poor prognosis. Although the 10% transformation rate (2.5% annually) in group A seemed to be extremely high compared with that in the general population of HTLV-I carriers (around 0.06% to 0.4% annually), the majority of group A subjects and some in group B showed stable clinical courses without transformation. Further, development of ATL was not observed in four group A subjects with HTLV-I-associated myelopathy (HAM), which is rarely associated with ATL. We propose to call this group of rather benign HTLV-I carriers "HTLV-I carriers with monoclonal proliferation of T lymphocytes (HCMPT)." Thus far we have been unable to identify reliable parameters other than WBC counts that prospectively distinguish HCMPT from the true pre-ATL state, in which there is a high probability of developing ATL. Further clinical and biologic approaches should elucidate the natural history of the HTLV-I carrier state and early events in ATL leukemogenesis.

A case of angiocentric immunoproliferative lesions (angiocentric lymphoma) associated with human T-cell lymphotropic virus type 1

We report a case of angiocentric immunoproliferative lesions (AILs; angiocentric lymphoma) in the subcutaneous tissue associated with human T-cell lymphotropic virus type 1 (HTLV-1). The patient showed an indolent cutaneous manifestation for 9 years until death. A skin biopsy revealed an angiocentric infiltration of atypical T lymphocytes and a marked coagulative necrosis, which are histologic hallmarks of AILs. Human T-cell lymphotropic virus type 1 antibody was detected by the indirect immunofluorescence test. The proviral integration of HTLV-1 also was confirmed in a DNA extract from paraffin sections using the polymerase chain reaction. The Epstein-Barr virus genome, which has been reported to be associated with AILs, could not be detected by polymerase chain reaction. The present case indicated that HTLV-1 also should be considered one of the pathogenetic factors of AILs.

Cloning and expression of large isoform of glutamic acid decarboxylase from human pancreatic islet

Glutamic acid decarboxylase (GAD) catalyzes formation of gamma-aminobutyric acid from glutamic acid and is a major autoantigen in insulin-dependent diabetes mellitus. Its two isoforms, GAD65 and GAD67, are encoded by two separate genes. We prepared human islet cDNA library and screened it with cDNA probes of rat brain GAD67. We cloned the cDNA for GAD67, the large isoform of glutamic acid decarboxylase, and determined its nucleotide sequence. Sequencing of the resulting clone identified a 1,785 residue open-reading frame encoded a 594 amino acid polypeptide that showed a 99.4% similarity with GAD67 from human brain. The bacterially expressed human islet GAD67 protein was enzymatically active and immunoreactive. The isolation of cDNA for this additional islet GAD isoforms will be important in studying the etiology and pathogenesis of IDDM.

fgr proto-oncogene is expressed during terminal granulocytic differentiation of human promyelocytic HL60 cells

In order to elucidate the function of the c-fgr protein tyrosine kinase, we have investigated the expression of c-fgr in the human promyelocytic cell line, HL60, during myeloid differentiation induced by dimethylsulfoxide (DMSO). The expression of c-fgr was preceded by growth arrest of DMSO-treated cells, as determined by [3H]-thymidine incorporation and colony-forming ability, and it became detectable when cells committed for terminal differentiation. The maximum expression was detected in the terminal stage of differentiation. The profile of tyrosine phosphorylation in cellular proteins was distinct among cells at various stages of the differentiation program. The 116 kd tyrosine-phosphorylated protein detected in exponentially proliferating HL60 cells diminished during the course of the growth arrest and a distinct profile of tyrosine phosphorylation (including 177 and 165 kd proteins) appeared in cells undergoing terminal granulocytic differentiation. These findings implicate the involvement of p55c-fgr in the process of terminal granulocytic differentiation. However, the tyrosine kinase activity of p55c-fgr expressed in differentiating HL60 cells was markedly inhibited by the tyrosine phosphatase inhibitor, sodium orthovanadate, suggesting the presence of a mechanism involving tyrosine phosphorylation that negatively regulates the kinase activity of p55c-fgr.

Maternal transmission of HTLV-1 other than through breast milk: discrepancy between the polymerase chain reaction positivity of cord blood samples for HTLV-1 and the subsequent seropositivity of individuals

We used a nested polymerase chain reaction (PCR) to diagnose HTLV-1 carriers. The DNA isolated from the nuclear extract obtained from frozen whole blood was found appropriate for PCR study both qualitatively and quantitatively. The use of freshly frozen whole blood made the field work much easier, and the use of a nuclear extraction procedure allowed DNA isolation in just 4 microcentrifuge tubes. We could not attain sufficient sensitivity to detect a single molecule with single-step PCR, but nested PCR was confirmed to detect a single molecule/reaction. All samples of the seropositive group including 94 blood donors, 66 mothers, and 13 children were positive in the nested PCR, while none of the seronegative group, including 198 blood donors and 285 children, was positive. Although 18/717 (2.5%) cord blood samples obtained from babies born to carrier mothers were PCR-positive, none of 5 formula-fed children tested who had been PCR-positive in the cord blood gave evidence of infection later on. Furthermore, all of 4 seropositive infected children who were formula-fed had been PCR-negative in their cord blood. The results are not consistent with intrauterine infection, but suggest the presence of a perinatal or postnatal infection route other than through breast milk.

Autoantibodies to 64,000-M(r) islet cell protein in long-term type 1 (insulin-dependent) diabetic patients

Autoantibodies to the 64,000-M(r) (64K) islet cell protein, identified as glutamic acid decarboxylase, were assayed in 46 Type 1 (insulin-dependent) diabetic patients with a disease duration of more than 5 years. Of 46 Type 1 diabetic patients, 18 (39.1%) were found to be positive for 64K antibodies and 12 of these patients had been diagnosed with autoimmune thyroid disease. Serum C-peptide levels were not detectable in 15 of 18 patients positive for 64K antibodies. The samples were also tested for titres of islet cell antibodies. Islet cell antibodies were detected in 15 (32.6%) of the 46 patients and all the islet cell antibody positive patients were also found to be positive for 64K antibodies. Furthermore, of these 15 patients 12 had previously been diagnosed with autoimmune thyroid disease. A correlation between levels of 64K antibodies and islet cell antibody titre revealed that higher levels of 64K antibodies were observed in patients who had higher islet cell antibody titre. These results demonstrate that most long-term Type 1 diabetic patients with 64K antibodies were also positive for islet cell antibodies complicated by autoimmune thyroid disease.

Intravascular ultrasound imaging in human peripheral and coronary arteries in vivo

To determine the feasibility of intravascular ultrasound imaging in vivo, a miniaturized high frequency transducer catheter was introduced into human peripheral (n = 10) and coronary (n = 4) arteries. Cross-sectional ultrasound images were obtained from iliofemoral arteries in 10 patients using a 20 MHz transducer catheter (1.2 mm in diameter) and from coronary arteries in 4 patients using a 30 MHz transducer catheter 5 French size (Fr) following successful coronary angioplasty. Ultrasound images obtained from peripheral arteries showed a three-layered appearance (echo-reflective intima, echo-lucent media and echo-reflective adventitia) in the normal arteries. In diseased arteries, the location, amount and extent of atheromatous plaque were clearly documented. The arterial diameters measured by ultrasound closely correlated with the measurements by angiography (r = 0.91) in the peripheral arteries. Coronary angiograms obtained following balloon angioplasty revealed smooth edges at the dilatation sites without significant narrowing in all patients. However, a significant amount of residual atheromatous plaque was clearly observed on the ultrasound images at the previously dilated sites. Coronary dissection, which was identified as an echo-lucent area behind the plaque, was noted in 2 patients. Ultrasound images also revealed the presence of calcium in the plaque which was unrecognized on the angiograms in 3 patients. In addition, direct measurement of the lumen cross-sectional area was possible on the ultrasound images.(ABSTRACT TRUNCATED AT 250 WORDS)

Diverse biologic properties imparted by the c-fgr proto-oncogene

The c-fgr proto-oncogene specifies a nonreceptor protein-tyrosine kinase, p55c-fgr, a member of the src family. In the present study, we have mutagenized c-fgr to mimic alterations found at the 3' end of the v-fgr oncogene and have investigated the biologic effects of normal and mutant p55c-fgr expression. Genes lacking 10 or 13 codons at the 3' end, as well as a gene encoding phenylalanine instead of tyrosine at codon 523, were potent oncogenes when transfected into NIH 3T3 cells. Specific enzymatic activities of the more highly transforming gene products were 3-4-fold greater than that of p55c-fgr. In vivo, the amount of tyrosine phosphorylation of cellular proteins was directly proportional to potency in focus-forming assays. These findings are the first to identify highly transforming mutations of the c-fgr proto-oncogene. The proto-oncogene was also active in transforming assays, demonstrably greater than that of a kinase-deficient mutant. Foci arising in c-fgr-transfected cultures expressed abundant enzyme that was normal by a number of criteria. In addition, growth rates for cells expressing p55c-fgr were restricted, as compared with cells expressing a kinase-deficient protein or cells transformed by proteins with high specific enzymatic activities. Thus, enzymatically active p55c-fgr can simultaneously activate transforming and growth inhibitory pathways.

Amplification of HTLV-1-related sequences among patients with neurological disorders in highly endemic Nagasaki: lack of evidence for association of HTLV-1 with multiple sclerosis

We studied DNA sequences homologous to HTLV-1 in peripheral blood mononuclear cells (PBMC) of 30 patients with neurological disorders in Kyushu, where HTLV-1 is highly endemic. The regions of HTLV-1 amplified by means of polymerase chain reaction (PCR) included U3, U5, gag, pol, env and pX. Our system specifically detected HTLV-1 sequences only from HTLV-1-positive cells and was sufficiently sensitive to detect one proviral copy per 10(3) PBMC. All PCR-positive cases were seropositive, including 4 cases of tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM) (4/4), and one case each of myasthenia gravis (1/7) and multiple sclerosis (1/8). The PCR-positive rate of patients, excluding 4 TSP/HAM cases, was 8% (2/26), which is similar to the seroprevalence of the adult population in the area. The data suggest that multiple sclerosis is not associated with prototype HTLV-1.

Oral infection of a common marmoset with human T-cell leukemia virus type-I (HTLV-I) by inoculating fresh human milk of HTLV-I carrier mothers

To obtain definitive evidence that milk-borne infection plays a critical role in the endemy or mother-to-child transmission of human T-cell leukemia virus type-I (HTLV-I), we inoculated concentrated fresh human milk cells obtained from HTLV-I carrier mothers into the oral cavity of a common marmoset (Callithrix jacchus). Twenty-eight milk samples were collected (5-10 ml each) from 17 carrier mothers in the first week after delivery. Cells in the milk were centrifuged down and resuspended in 1/10 vol of the milk fluid. The concentrated cell suspensions were successively inoculated into the oral cavity of a common marmoset. The marmoset was found to be seroconverted by indirect immunofluorescence assay at 2.5 months after the first inoculation of the milk (3.5 X 10(8) cells in total), and was later confirmed to be infected with HTLV-I by the detection of viral antigen expression in short-term cultures of its peripheral blood T-lymphocytes. The results strongly support the working hypothesis that milk-borne infection plays a significant role in the mother-to-child transmission of HTLV-I.

Oral transmission of human T-cell leukemia virus type-I into a common marmoset (Callithrix jacchus) as an experimental model for milk-borne transmission

To obtain experimental support for possible milk-borne infection of human T-cell leukemia virus type-I (HTLV-I), short-term-cultured viral antigen-positive lymphocytes obtained from peripheral blood of adult T-cell leukemia lymphoma complex (ATLL) patients were inoculated into the oral cavity of two adult common marmosets (Callithrix jacchus) in amounts comparable to those of HTLV-I-carrying cells fed to a baby in the milk of seropositive mothers. One of the animals seroconverted 2.5 months after the first inoculation. Cultures of peripheral blood mononuclear leukocytes of the marmoset revealed HTLV-I antigen expression in cells, indicating the establishment of oral infection of HTLV-I in an adult marmoset. The cell number deduced to be responsible for the infection was 5.6 X 10(7) cells (used in the first 2 inoculations). The results suggest that the concept of milk-borne infection of HTLV-I from a seropositive mother to her child is plausible.

Sera of adult T-cell leukemia patients and carriers of human T-cell leukemia virus type I in Japan do not cross-react with antigens of lymphadenopathy virus

The immunological cross-reactivity of human T-cell leukemia virus type I (HTLV-I)-related sera with lymphadenopathy virus (LAV) was investigated. The sera tested were obtained from 36 adult T-cell leukemia patients, 182 HTLV-I carriers, and 284 control individuals in Nagasaki. Two test methods were utilized: indirect immunofluorescence on LAV-producing cells and solid-phase radioimmunoassay with lysate of LAV. The results were exclusively negative for the presence of antibody activity against LAV, indicating the absence of cross-reaction and endemy in Nagasaki.