Neuroprotective mechanisms of lidocaine against in vitro ischemic insult of the rat hippocampal CA1 pyramidal neurons

To compare neuroprotective effects of lidocaine and procaine against ischemic insult, intracellular recordings were made from rat hippocampal CA1 pyramidal neurons in slice preparations. Superfusion of the slices with oxygen- and glucose-deprived medium (in vitro ischemia) produced a rapid depolarization 6 min from the onset. When oxygen and glucose were reintroduced, the membrane depolarized further until it reached 0 mV, and thereafter the membrane showed no functional recovery. Pretreatment with lidocaine (10 microM), but not procaine (50 microM), restored the membrane potential after the reintroduction of oxygen and glucose. Lidocaine, compared to procaine, significantly inhibited the reduction in both tissue ATP content and flavoprotein fluorescence during and after in vitro ischemia. Under electron microscopy, only lidocaine well preserved the structure of mitochondria in the CA1 pyramidal cell body. Extracellular recordings revealed that procaine reduced the field postsynaptic potential whereas lidocaine augmented it. Both drugs reduced the presynaptic volley dose-dependently. Neither lidocaine nor procaine significantly affected a rapid rise of the intracellular Ca2+ level produced by in vitro ischemia in the CA1 region. All the results suggest that the neuroprotective lidocaine action is due to the protection of the mitochondria to maintain the tissue ATP content during and after in vitro ischemia.

Importance of early repair of isolated abdominal aortic dissecting aneurysm

BACKGROUND

Since the available information on isolated abdominal aortic dissecting aneurysm (AADA) is mainly related to case reports or reports of small groups of patients, its natural history remains undetermined and there is no agreement on its optimal management. The purpose of this study is to define the features and pattern of development of this unusual entity as well as to propose criteria for treatment based on our own experience and previously published data.

PATIENTS AND METHODS

We retrospectively evaluated the history of 6 patients diagnosed with AADA. The patients were 5 males and 1 female. The mean age was 71 +/- 8 years (range: 61-80 years), and the mean aneurysm diameter was 54 +/- 14 mm (range: 35-70 mm). All of these patients were hypertensive (100%). History of cerebrovascular accident, ischemic heart disease, peripheral arterial disease, or diabetes mellitus was present in 1 patient, respectively. Two patients developed mycotic AADA.

RESULTS

Emergency operations had been performed in 3 cases, and scheduled surgical reconstruction in the remaining 3 cases. Operation consisted of aneurysmectomy and graft replacement of the diseased aortic segment in all cases. One patient treated in an emergency setting died subsequently of multisystem organ failure, but the others did well.

CONCLUSION

Symptomatic patients or patients at good risk should undergo surgical repair earlier than in the case of abdominal aortic aneurysm without dissection (AAA). Dissection in addition to an AAA will further increase the weakness of the aortic wall and the possibility of aortic rupture will become higher.

Analysis of cellular localization of SART3 tumor antigen by a newly established monoclonal antibody: heterotopic expression of SART3 on the surface of B-lineage leukemic cells

SART3 has been identified as a tumor antigen recognized by cytotoxic T-lymphocytes. Subcellular localization of SART3 is still controversial, although it has been studied extensively. In this study, we established an anti-SART3 monoclonal antibody (mAb) to analyze the subcellular localization of SART3 in tumor specimens. Immunohistochemical analysis demonstrated that SART3 was preferentially expressed in the nucleus of cancer cells. Flow cytometric analysis indicated that SART3 was not expressed on the cell surface of tumor cells, except for B-lineage cells. SART3 was detected on the cell surface of several B-lineage leukemic cells with different maturation stages, but not on normal peripheral blood B cells. These results suggest that heterotopically expressed SART3 is a tumor-associated antigen rather than a differentiation antigen on B-lineage cells.

A polymorphism in the CYP17 gene relates to the risk of recurrent pregnancy loss

The CYP17 gene encodes the enzyme cytochrome P450c17alpha, which mediates both 17alpha-hydroxylase and 17,20-lyase activity in the steroid biosynthesis pathway. A T-->C polymorphism in the 5' promoter region of CYP17 has been described. To examine the association between recurrent pregnancy loss (RPL) and a polymorphism in CYP17, a case-control study of 117 cases with RPL and 164 controls was conducted. This polymorphism was investigated by PCR/restriction fragment length polymorphism using DNA from peripheral lymphocytes. The T-->C transition in the variant allele (A2) creates a new recognition site for the restriction enzyme MspA1, which permits designation of the wildtype allele (A1) and A2. Women with the A2 allele of CYP17 had an increased risk of RPL [A1/A1 genotype (reference); A1/A2 genotype: odds ratio (OR), 1.68; 95% confidence interval (CI), 0.94-3.01; A2/A2 genotype: OR, 2.37; 95% CI, 1.16-4.83; P trend, 0.016]. Additionally, there was a similar tendency for the increased risk of primary RPL [A1/A1 genotype (reference); A1/A2 genotype: OR, 2.14; 95% CI, 1.14-4.01; A2/A2 genotype: OR, 2.50; 95% CI, 1.16-5.41; P trend, 0.015]. These results suggest that possession of the A2 variant of CYP17 may predispose to an increased risk of RPL with a gene dosage effect.

Characterization of the eicosapentaenoic acid biosynthesis gene cluster from Shewanella sp. strain SCRC-2738

The 38 kb eicosapentaenoic acid (EPA) biosynthesis gene cluster of Shewanella sp. strain SCRC-2738 was cloned into the cosmid vector (pEPA). A 27 kb nucleotide sequence of the XhoI to SpeI region of pEPA showed EPA production (6.3%) in E. coli JM109. Among the nine open reading frames (ORFs) in this sequence, only five (ORFs 2 and 5-8) were essential for EPA production. High levels of production (16%-22%) were found in E. coli JM109 transformed with a multicopy pNEB vector carrying only the five essential ORFs and in that transformed with a pNEB vector that integrated ORFs 3, 5, 6, 7 and 8, and vector pSTV28 that integrated the ORF2 encoding phosphopantetheinyl transferase (PPTase). Thus, production of EPA appears to be regulated by the presence of all the biosynthesis gene products and by the ratio of PPTase to the other gene products. The temperature -EPA production relationship in E. coli strain DH5alpha varied between constructs, suggesting that it is controlled not only by EPA biosynthesis enzymes but also by other factors in vivo. There was a strict upper temperature limit for EPA biosynthesis: no EPA was synthesized at 30 degrees C in E. coli transformants carrying any gene construct for EPA biosynthesis.

A phase I trial of cytotoxic T-lymphocyte precursor-oriented peptide vaccines for colorectal carcinoma patients

In most protocols of peptide-based vaccination, no consideration has been paid to whether or not peptide-specific cytotoxic T-lymphocyte (CTL) precursors are pre-existent in cancer patients. Initiation of immune boosting through vaccination is better than that of immune priming to induce prompt and strong immunity. In this study, 10 human histocompatibility leukocyte antigen-A24⁺ patients with advanced colorectal carcinomas were treated with up to four peptides that had been positive for pre-vaccination measurement of peptide-specific CTL precursors in the circulation (CTL precursor-oriented peptide vaccine). No severe adverse effect was observed, although local pain and fever of grade I or II were observed. Post-vaccination peripheral blood mononuclear cells (PBMCs) from five patients demonstrated an increased peptide-specific immune response to the peptides. Increased CTL response to cancer cells was detected in post-vaccination PBMCs of five patients. Antipeptide immunoglobulin G became detectable in post-vaccination sera of seven patients. Three patients developed a positive delayed-type hypersensitivity response to at least one of the peptides administrated. One patient was found to have a partial response; another had a stable disease, sustained through 6 months. These results encourage further development of CTL precursor-oriented vaccine for colorectal cancer patients.

Characterization of Oita virus 296/1972 of Rhabdoviridae isolated from a horseshoe bat bearing characteristics of both lyssavirus and vesiculovirus

Oita virus 296/1972 was isolated from the blood of a wild horseshoe bat, Rhinolophus cornutus (Temminck) in 1972. We investigated the pathogenicity of this virus in mice in relation to its histological, immunohistochemical and ultrastructural characteristics and the entire sequence of nucleoprotein gene. This virus caused lethal encephalitis in mice through intracerebral route. This susceptibility of mice was until 3 weeks of age. Immunohistochemical analysis using the convalescent sera obtained from survived adult mice after intracerebral inoculation revealed that many neurons were positive in the cytoplasm, besides no cross reactivity with normal and rabies virus-infected mouse brain tissues to this anti-sera. Ultrastructural analysis disclosed many bullet-shaped and enveloped virions in neurons. These morphological characteristics of the virions are consistent of that of viruses in the family Rhabdoviridae. Budding from endoplasmic membrane suggests that this virus has a similarity with lyssaviruses. Molecular analysis of cDNA coding a tentative nucleoprotein sequence revealed homology with those of viruses in the family Rhabdoviridae. Distance matrix analysis of this gene sequence with those of other rhabdoviruses isolated from mammals disclosed the discrete position of this virus in the phylogenic tree of rhabdoviridae infecting mammals and we renamed this virus as Oita rhabdovirus.

Arachidonic acid metabolites contribute to the irreversible depolarization induced by in vitro ischemia

Intracellular recordings were made from hippocampal CA1 neurons in rat slice preparations. Superfusion with oxygen- and glucose-deprived medium (in vitro ischemia) produced a rapid depolarization approximately 5 min after the onset of the superfusion. Even when oxygen and glucose were reintroduced immediately after rapid depolarization, the membrane depolarized further (persistent depolarization) and reached 0 mV (irreversible depolarization) after 5 min from the reintroduction. The pretreatment of the slice preparation with a phospholipase A2 (PLA2) inhibitor, para-bromophenacyl bromide, or a cytochrome p-450 inhibitor, 17-octadecynoic acid, significantly restored the membrane to the preexposure potential level after the reintroduction of oxygen and glucose. The administration of 14,15-epoxyeicosatrienoic acid or 20-hydroxyeicosatetraenoic acid did not change the latency of the rapid depolarization and did not allow the membrane potential to recover after the ischemic exposure. In contrast, after pretreatment with cyclooxygenase or lipoxygenase inhibitors, such as indomethacin, resveratrol, Dup-697, nordihydroguaiaretic acid, and 3,4-dihydrophenyl ethanol, a minority of neurons tested showed postischemic recovery from the persistent depolarization. Improved recovery was also seen after treatment with the free radical scavengers, edaravone and alpha-tocopherol. These results suggest that the activation of the arachidonic acid cascade via PLA2 and the free radicals produced by arachidonic acid metabolism contribute to the irreversible depolarization produced by in vitro ischemia.

Inhibition of arthritis by systemic administration of endostatin in passive murine collagen induced arthritis

OBJECTIVE

To investigate the arthritis inhibiting effect of endostatin, known to have potent antiangiogenic activity, systemically given to animal models of rheumatoid arthritis (RA).

METHODS

Four kinds of monoclonal anti-type II collagen antibody followed by lipopolysaccharide (LPS) three days later were given to 6 week old, female Balb/c mice to induce arthritis. Three groups of mice received 0.2 mg/kg/day, 2 mg/kg/day, and 10 mg/kg/day of endostatin, respectively, whereas a control group received phosphate buffered saline (PBS). Endostatin or PBS was given for 13 days, starting before the development of arthritis. Arthritis was evaluated by arthritis scores and hind paw thicknesses. Mice were killed for histological examination on the 22nd day after the administration of monoclonal anti-type II collagen antibody.

RESULTS

Arthritis developed within three days after LPS administration in both the control and endostatin treatment groups. No difference in the development rate of arthritis was noted between the control and endostatin treatment groups. Arthritis scores remained significantly lower in the endostatin 10 mg/kg/day group than in the control group. Hind paw thicknesses also remained significantly smaller in the endostatin 10 mg/kg/day group than in the control group. Histopathological examination showed that synovial thickening and subchondral bone erosion improved more in the endostatin treatment groups than in the control group.

CONCLUSION

The systemic administration of endostatin had an arthritis inhibiting effect in RA animal models. Endostatin inhibited, in particular, pannus formation and bone destruction.

IgG reactive to CTL-directed epitopes of self-antigens is either lacking or unbalanced in atopic dermatitis patients

We previously demonstrated that CTL-directed epitopes derived from non-mutated self-antigens elicit a type-I allergy in the majority of healthy donors (HD) as did the presence of IgE and IgG reactive to these peptides in the sera of the donors. We investigated in this study whether Igs reactive to eight types of CTL-directed peptides were elevated in the sera of 40 patients with atopic dermatitis (AD). Total IgE levels in the sera of AD patients were significantly higher than those of HD, however, no significant differences between the AD patients and the HD were observed in either the serum levels or the positive rates of IgE reactive to seven of the eight peptides. Total IgG levels were not different from each other, however, IgG reactive to the two peptides with no sequence similarity to other species and one peptide that had similarity to DNA helicase II of enterobacteria were not detectable in the sera of the AD patients. Although IgG reactive to the remaining five peptides, which had sequence similarity to other species, were detectable in both the AD patients and the HD, ratios of peptide-specific IgG1/IgG2 were mostly lower in the AD patients than in the HD. These results indicate that IgG reactive to CTL-directed epitopes of self-antigens is either lacking or unbalanced in AD patients. This information may provide new insight into the immune-mechanisms of elevated auto-reactivity of AD patients.

Persistence of systolic coronary flow reversal predicts irreversible dysfunction after reperfused anterior myocardial infarction

OBJECTIVE

To investigate serial assessments of systolic coronary flow reversal in the infarct related artery for predicting poor left ventricular functional recovery after reperfused acute myocardial infarction.

SETTING

Regional hospital.

PATIENTS AND METHODS

49 patients with anterior acute myocardial infarction had transthoracic Doppler echocardiography to record coronary flow velocity in the left anterior descending coronary artery immediately after successful primary coronary angioplasty (day 0), and at 48 hours, one week, and three weeks.

MAIN OUTCOME MEASURES

Coronary flow velocity at each time point; regional wall motion score index (RWMSI) at day 0 and at three weeks. Irreversible dysfunction was defined as a decrease in RWMSI to < 0.22.

RESULTS

Measurements of coronary flow velocity could be made in 45 patients. Patients were divided into three groups: no systolic flow reversal (group 1, n = 27), systolic flow reversal observed only on day 0 (group 2, n = 8), and systolic flow reversal persisting until 48 hours (group 3, n = 10). Although baseline RWMSI was similar among the three groups, the value at three weeks was significantly higher in group 3 than in the other two groups. In predicting irreversible dysfunction, the persistence of systolic flow reversal up to 48 hours had a higher positive predictive value (100%) than the presence of systolic flow reversal on day 0 (67%, p < 0.04). The negative predictive value of systolic flow reversal at 48 hours (83%) was comparable in accuracy to the presence of systolic flow reversal on day 0 (85%, NS).

CONCLUSIONS

In reperfused anterior acute myocardial infarction, serial assessment of coronary flow velocity in the left anterior descending coronary artery is feasible using transthoracic Doppler echocardiography, and the persistence of systolic flow reversal at 48 hours is a more specific marker of irreversible dysfunction than peak creatine kinase or diastolic deceleration time.

Identification of an amino acid responsible for the CD3 polymorphism in cynomolgus monkeys (Macaca fascicularis)

The FN18 monoclonal antibody (mAb), directed to CD3 molecules, did not react with the lymphocytes of some cynomolgus monkeys (Macaca fascicularis), because of the polymorphism of the CD3epsilon chain. The epitope recognized by the FN18 mAb was successfully expressed on COS7 cells upon transfection of plasmid DNA coding for the CD3epsilon derived from T cells of a FN18 positive cynomolgus monkey. By construction and expression of plasmid DNA encoding the mutant CD3epsilon, the amino acid residue at position 67 was demonstrated to be involved in the formation of an epitope recognizable by the FN18 mAb.

Identification of ribosomal proteins S2 and L10a as tumor antigens recognized by HLA-A26-restricted CTL

Recent identification of cytotoxic T lymphocyte (CTL)-directed peptides binding to the HLA-A2 and -A24 alleles has opened the door to peptide-based cancer immunotherapies. However, subsequent studies have succeeded in identifying no more than a few CTL-directed peptides that bind to alleles other than HLA-A2 and -A24, thus hampering development of immunotherapies directed at other alleles. We have shown in this study that two genes coding for ribosomal proteins (S2 and L10a) encoded tumor antigens recognized by HLA-A26-restricted CTLs. The S2 mRNA was expressed in all of the cancer cells and non-malignant cell lines tested, but was not expressed in normal tissues except for the testis, muscle, and peripheral mononuclear leukocyte cell (PBMC). In contrast, the L10a mRNA was expressed in all of these cancer and non-malignant cell lines, and also normal tissues, although the expression levels in normal tissues were mostly low. One S2-derived peptide and two L10a-derived peptides had the ability to induce HLA-A26-restricted and peptide-specific CTLs reactive to tumor cells in PBMCs of cancer patients, respectively. These ribosomal protein-derived peptides, and particularly the S2-derived peptide, could be suitable for use in peptide-based immunotherapy for HLA-A26+ cancer patients.

UDP-Gal: betaGlcNAc beta1, 3-galactosyltransferase, polypeptide 3 (GALT3) is a tumour antigen recognised by HLA-A2-restricted cytotoxic T lymphocytes from patients with brain tumour

Patient prognosis in the case of malignant brain tumours is generally poor, despite significant improvements in the early detection of the tumours, and thus the development of new treatment modalities is needed. One of the most prominent modalities is specific immunotherapy, for which the elucidation of antigenic molecules of malignant brain tumours recognized by T cells is essential. We report here a gene, UDP-Gal: betaGlcNAc beta1, 3-galactosyltransferase, polypeptide 3, encoding three epitope peptides recognised by tumor-reactive cytotoxic T lymphocytes in an HLA-A2-restricted manner. Two of the three peptides possessed an ability to induce HLA-A2-restricted and tumour-reactive cytotoxic T lymphocytes from peripheral blood mononuclear cells of patients with brain tumours. These peptides may be useful in the peptide-based specific immunotherapy for patients with malignant brain tumours.

[Minimal incision abdominal aortic aneurysm repair]

OBJECTIVE

The use of a limited incision for abdominal aortic aneurysm (AAA) repair was evaluated, and its outcome was analyzed in comparison to standard open repair.

PATIENTS AND METHODS

Between February 2000 and August 2001, 20 patients with an AAA underwent minimal incision repair (MINI) for tube graft implantation. The minimal skin incision was made after localization of aneurysm neck and aortic bifurcation by CT and DSA. For repair of the upper part of the AAA the abdominal incision was retracted toward the head of the patient who was in a jackknife decubitus position. Conversely, when the peripheral portion of the AAA was treated, the abdominal incision was retracted caudally with the patient in a flat or slightly bent decubitus position. The operation itself was performed using the standard conventional technique. The length of the abdominal incision was 10 cm. Clinical characteristics and in-hospital outcome of this procedure were compared to a group of patients who underwent repair of AAA by means of a standard open technique (OPEN).

RESULTS

Patients age in the MINI and OPEN groups were similar (69 +/- 11 vs. 69 +/- 9 years). However, there were significant differences between the MINI and OPEN groups in the time for starting oral intake of food (2,4 +/- 1,2 vs. 7,4 +/- 5,5 postoperative days, p = 0,003), time for starting to walk outside the room (2,2 +/- 0,7 vs. 4,6 +/- 2,2 postoperative days, p = 0,01) and operation times (197 +/- 37 vs. 294 +/- 83 min, p = 0,0004).

CONCLUSION

Minimal incision repair is technically feasible and combines the benefits of a minimal incision with those of conventional open repair, reducing patient recovery time.

[Surgical treatment of cardiovascular manifestations of Marfan syndrome]

The present study determines the effect of surgical treatment of cardiovascular manifestations of Marfan syndrome in 72 patients by 114 operations, during 34-year period. This therapy resulted in aortic root repair, aortic arch replacement, or both in 78, mitral valve repair in 9, descending thoracic aortic replacement in 14, thoracoabdominal aortic replacement in 10, and abdominal aortic replacement in 6, including total aortic replacement in 4 and nearly total aortic replacement in 4 patients. Fusiform aneurysms were present in the the ascending aorta in 37, the aortic arch in 2, the thoracoabdominal aorta in 2, and the abdominal aorta in 6 patients. Aortic dissection occurred in 40 (55.6%), including type A aortic dissection in 29 patients. Aortic root repair included separate valve-graft in 8, Bentall composite valve-graft in 25, composite valve-graft with button technique in 26, composite valve-graft with interposition graft technique in 10, and valve sparing procedure in 5 patients. The overall early (30-day) mortality was 7.9%. The early survival was 75% in separate valve-graft procedure and 99.2% in composite valve-graft procedure. Late coronary dehiscence did not occur in the patients with Bentall technique in which the reattachments of coronary ostia were performed in 2 layers, but occurred in 50% of patients with the coronary anastomoses in 1 layer. Aortic valve regurgitation relapsed in 2 of the 5 patients with valve sparing procedure. Event free rate for the patients with composite valve-graft using button technique was 81.1% at 10 years. There were 14 late deaths; dissection or rupture of the residual aorta, composite graft endocarditis and cardiac failure were the principle causes of late deaths. In conclusion, Marfan patients with cardiovascular diseases can undergo surgical treatment with a low operative risk and low morbidity. Although late endocarditis remains a serious problem, we believe that Marfan syndrome is a contraindication for valve sparing procedure. Because of the potential for late dissection or aneurysm in other areas of the aorta, patients with Marfan syndrome should have serial computed tomographic scans indefinitely.

Personality, social support, coping and emotional distress after repeated spontaneous abortions

Systematic investigations on the emotional impacts of repeated spontaneous abortions have been few. We mounted a prospective study of a cohort of couples who had experienced two consecutive first trimester spontaneous abortions and for whom no clearly identifiable causes were found. The present report is based on the first part of the study and examines: (1) emotional distress reported by the miscarrying women at six months (median, range 1-12 months) after two abortions; and (2) psychosocial predictors influencing such distress. The mean score of the women on the Symptom Checklist 90-Revised--one of the most popular self-report scales for psychopathology--was 0.38, whereas that for the general population is reported to be 0.26 (the higher the score, the more psychopathology). Fourteen percent of the cohort scored above the cutoff point for mental disorders screening. Factors examined and found non-influential upon the level of emotional distress include: the maternal age; whether the last pregnancy was planned and wished for or not; and coping styles of the women after the abortions. Control by the husbands over the marital relationship and neurotic personality traits of the women increased the emotional distress, whereas the social support the women perceive decreased it. These findings suggest that martial and social support are important in determining the level of psychiatric morbidity after repeated abortions.

Mode of inheritance of HLA-DRB1 shared epitope in Japanese familial rheumatoid arthritis

OBJECTIVE

To clarify the mode of genetic contribution of the HLA-DR shared epitope (SE) to the pathogenesis of familial cases of Japanese rheumatoid arthritis (RA).

METHODS

Fifty-three unrelated Japanese RA families that had more than 2 affected sibs were selected. The HLA-DR shared epitope typing was carried out by the PCR method and PCR-SSCP (single stranded DNA conformation polymorphism) method. Affected sib pair analysis was carried out using the MAPMAKER/SIB 2.0 program. The mode of inheritance was also calculated based on the sharing of genes identical by descent (IBD) between siblings in each of the 53 affected sib-pairs (propositus and the 2nd affected sib).

RESULTS

The maximum LOD score of HLA-DR was 0.437, and the sharing of 2 IBDs, 1 IBD, and no IBDs between affected sibs were 0.330, 0.500, and 0.170, respectively. The sharing distribution of IBD was confirmed to be compatible with the dominant or additive mode since the observed gene frequency of SE was 0.255.

CONCLUSION

The HLA-DR shared epitope participated in the pathogenesis of familial cases of Japanese RA. The SE contributes to this pathogenesis in either the dominant or additive mode of inheritance.

Room temperature scanning Hall probe microscopy using GaAs/AlGaAs and Bi micro-hall probes

A room temperature scanning Hall probe microscope system utilizing GaAs/AlGaAs and bismuth micro-Hall probes was used for magnetic imaging of ferromagnetic domain structures on the surfaces of crystalline thin film garnets and permanent magnets. The Bi micro-Hall probes had dimensions ranging between 0.25 and 2.8 microm2 and were fabricated using a combination of optical lithography and focused ion beam milling. The use of bismuth was found to overcome surface depletion effects associated with semiconducting micro-Hall probes. Our experiments demonstrated that Bi is a practical choice of material for fabricating sub-micron sized Hall sensors.

Increased plasma HB-EGF associated with obesity and coronary artery disease

The mechanism by which the obese subjects are more associated with vascular disease remains unclear. We reported that the adipose tissues produce and secrete many bioactive molecules, conceptualized as adipocytokines. Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), produced locally by vascular macrophages and smooth muscle cells, has been suggested to induce the migration and proliferation of vascular smooth muscle cells. The current study reveals that (1) HB-EGF mRNA is abundantly expressed in human adipose tissue, (2) HB-EGF mRNA increases in the fat tissues of obese mice, (3) plasma HB-EGF levels increase in parallel with fat accumulation in human, and (4) the subjects with coronary artery disease have higher plasma HB-EGF levels, associated with fat accumulation. These results suggest that increased plasma HB-EGF derived from the accumulated fat contributes to the higher incidence of vascular disease in obesity, proposing HB-EGF as an adipocytokine directly linking adipovascular axis.

Non-mutated tumor-rejection antigen peptides elicit type-I allergy in the majority of healthy individuals

IgE-mediated type-I allergy is generally considered to be a hypersensitivity reaction to foreign antigens, and it is believed that self-antigens do not evoke this type of allergy. We report here, for the first time, that non-mutated self-antigen peptides identified as tumor-rejection antigen peptides recognized by HLA class I-restricted and tumor-specific cytotoxic T lymphocytes (CTLs) elicited a type-I allergy in the majority of healthy individuals. Peptide-specific IgE was detectable in sera from certain cases, although the levels did not always correlate with those of type-I allergy. Repeated vaccinations of nonallergic peptides derived from the same antigens possessing allergic peptides resulted in the suppression of both allergic peptide-specific IgE responses and type-I allergy, providing evidence for a new approach to the development of peptide-based desensitization.

Calcium-sensing receptor gene polymorphism affects the parathyroid response to moderate hypercalcemic suppression in patients with end-stage renal disease

AIM

The basic mechanism of secondary hyperparathyroidism is still unclear, but a change in Ca2+ sensing by parathyroid cells is possibly involved in this uremic complication. A rightward shift of the calcium set-point and an increase of the minimum secretion rate have been found in secondary hyperparathyroidism, indicating abnormal calcium sensing.

METHODS

We evaluated the effect of calcium sensing receptor (CaR) gene polymorphism (codon G990R) on the response of the parathyroid gland to moderate hypercalcemic suppression in 77 ESRD patients on regular hemodialysis (HD using 2.5 mEq/l Ca2+ dialysate). All patients underwent an HD session with 3.0 mEq/l Ca2+ dialysate to suppress parathyroid hormone (PTH). Then we investigated the effect of CaR gene polymorphism on the parathyroid response to hypercalcemic stimulation.

RESULTS

Patients were divided into 3 groups on the basis of genotype (GG = 33 patients (42.9%), GR = 39 patients (50.6%), RR = 5 patients (6.5%)). Baseline intact PTH levels in patients without the R allele were not significantly different from those in patients with the R allele (GG group, 181.4 +/- 31.1 pg/ml vs. GR and RR groups, 230 +/- 51.2 pg/ml: mean +/- SEM). The significant effect of moderate hypercalcemic suppression on the intact PTH level was observed in the GG group (p < 0.01) but not in the GR and RR groups, despite the identical increase in Ca2+.

CONCLUSION

Our results suggest that CaR gene polymorphism (codon G990R) influences the responsiveness of the parathyroid gland to changes of extracellular Ca2+ in ESRD patients. The glands of patients with the GG genotype of the CaR gene may be more sensitive to extracellular Ca2+ changes.

Suppression of membrane-type 1 matrix metalloproteinase (MMP)-mediated MMP-2 activation and tumor invasion by testican 3 and its splicing variant gene product, N-Tes

Using expression cloning to screen a human fetal kidney cDNA library for regulator(s) of pro-matrix metalloproteinase (MMP)-2 processing mediated by membrane-type (MT) 1 MMP, we isolated a cDNA whose product interfered with pro-MMP-2 activation. It encodes the NH(2)-terminal 313-amino acid region of a calcium-binding proteoglycan, testican 3, with a 3-amino acid substitution at the COOH terminus and thus was named N-Tes. N-Tes comprises a signal peptide, a unique domain, a follistatin-like domain, and a Ca(2+)-binding domain but lacks a COOH-terminal thyroglobulin domain and two putative glycosaminoglycan attachment sites of testican 3. Pro-MMP-2 activation by MT3-MMP was also inhibited by the coexpression of N-Tes. Immunoprecipitation analysis demonstrated direct interaction of N-Tes with either MT1-MMP or MT3-MMP. Expression of testican 1 or testican 3 but not testican 2 also inhibited pro-MMP-2 activation by either MT1-MMP or MT3-MMP. Deletion and substitution of amino acids residues in N-Tes revealed that the unique NH(2)-terminal domain of N-Tes is responsible for the inhibition of pro-MMP-2 activation by MT-MMPs. Expression of N-Tes and testican 3 was detected in normal brain but down-regulated in glioma tissues. Transfection of either the N-Tes or testican 3 gene into U251 glioma cells or Madin-Darby canine kidney cells transformed by erbB2 suppressed their invasive growth in collagen gel. These results suggest that both N-Tes and testican 3 would interfere with tumor invasion by inhibiting MT-MMPs.

Induction of cellular immune responses to tumor cells and peptides in colorectal cancer patients by vaccination with SART3 peptides

The tumor-rejection antigen SART3 possesses two antigenic epitopes (SART3(109-118) and SART3(315-323)) capable of inducing HLA-A24-restricted and tumor-specific CTLs. To determine its safety and ability to generate antitumor immune responses, 12 patients with advanced colorectal cancer were administered s.c. vaccinations of these peptides. No severe adverse events were associated with the vaccinations. Significant levels of increased cellular immune responses to both HLA-A24+ colon cancer cells and the vaccinated peptide were observed in the postvaccination peripheral blood mononuclear cells in 7 of 11 and 7 of 10 patients tested, respectively, and the higher responses were observed in those patients vaccinated with the highest dose (3 mg/injection) of the peptides. These results encourage further development of SART3 peptide vaccine for colorectal cancer patients.

Catalase catalyzes nitrotyrosine formation from sodium azide and hydrogen peroxide

Sodium azide (NaN3) is known as an inhibitor of catalase, and a nitric oxide (NO) donor in the presence of catalase and H2O2. We showed here that catalase-catalyzed oxidation of NaN3 can generate reactive nitrogen species which contribute to tyrosine nitration in the presence of H2O2. The formation of free-tyrosine nitration and protein-bound tyrosine nitration by the NaN3/catalase/H2O2 system showed a maximum level at pH 6.0. Free-tyrosine nitration induced by peroxynitrite was inhibited by ethanol and dimethylsulfoxide (DMSO), and augmented by superoxide dismutase (SOD). However, free-tyrosine nitration induced by the NaN3/catalase/H2O2 system was not affected by ethanol, DMSO and SOD. NO2- and NO donating agents did not affect free-tyrosine nitration by the NaN3/catalase/H2O2 system. The reaction of NaN3 with hydroxyl radical generating system showed free-tyrosine nitration, but no formation of nitrite and nitrate. The generation of nitrite (NO2-) and nitrate (NO3-) by the NaN3/catalase/H2O2 system was maximal at pH 5.0. These results suggested that the oxidation of NaN3 by the catalase/H2O2 system generates unknown peroxynitrite-like reactive nitrogen intermediates, which contribute to tyrosine nitration.

Recipient MHC class II expression is required to achieve long-term survival of murine cardiac allografts after costimulatory blockade

To study the role of the direct and indirect pathways in achieving tolerance, we used genetically altered mouse strains in two ways: 1) MHC class II-deficient mice were used as donors of skin and cardiac grafts to eliminate the direct CD4(+) T cell response, and 2) B6 II(-)4(+) mice, which are MHC class II-deficient mice expressing an MHC class II transgene only on thymic epithelium, were used as recipients of normal grafts. These mice cannot mount an indirect response. Eliminating the indirect pathway actually made it more difficult to achieve prolonged allograft survival when we used costimulatory blockade than when both pathways were available. Costimulatory blockade was ineffective even when CD4(+) T cells from normal animals were transferred into recipients that lacked MHC class II molecules. These results suggest that an active CD4(+) response through the indirect pathway is necessary for costimulatory blockade to be effective in prolonging allograft survival.

Vitamin D receptor gene polymorphism detected by digestion with Apa I influences the parathyroid response to extracellular calcium in Japanese chronic dialysis patients

BACKGROUND

To play its physiological role, 1,25(OH)2D3 must bind to a specific vitamin D receptor (VDR) in the nucleus. We have previously reported that VDR gene polymorphism influences the parathyroid function in patients with end-stage renal disease (ESRD). In the present study, we have investigated the relationship between the parathyroid responsiveness and VDR gene polymorphism, as detected by the Apa I restriction enzyme, by changing the concentration of Ca2+ in the dialysate.

METHODS

58 Japanese ESRD patients undergoing renal replacement therapy in our institution were evaluated. Genomic DNA was extracted from peripheral leukocytes and digested at the intron between exon 8 and exon 9 of the VDR gene using Apa I enzyme. Then alleles were classified into genotype A (undigested allele) and genotype a (digested allele). Extracellular ionized calcium ([Ca2+]e), serum phosphate, and intact parathyroid hormone (PTH) were measured before and after each hemodialysis (HD) session with dialysates having different concentrations of Ca2+ (1.5 or 1.25 mmol/l). The significance of differences in statistical analyses was defined within confidence limits of 5.0%.

RESULTS

The AA, Aa, and aa genotypes were observed in 7/58 patients (12.1%), 23/58 patients (39.6%), and 28/58 patients (48.3%), respectively. The PTH reduction after HD with the 1.5-mmol/l Ca dialysate did not differ significantly between group AA+Aa and group aa. On the other hand, the PTH increase was significantly higher in group aa than in group AA+Aa after HD with the 1.25-mmol/l Ca dialysate (p = 0.0107), despite a similar PTH level before HD. Similarly, the percent increase of PTH after HD with the 1.25-mmol/l Ca dialysate was significantly higher (p = 0.0112) in group aa (50.2 +/- 9.4%) than in group AA+Aa (19.7 +/- 7.2%). There were no significant differences between the two groups in [Ca2+]e nor in serum phosphorus (Pi) before and after HD with either dialysate. Group AA+Aa and group aa did not show statistically significant differences in age, female/male ratio, ratio of diabetic nephropathy, or dialysis period.

CONCLUSIONS

The study results showed that the patients in group aa were more sensitive to changes in [Ca2+]e than those in group AA+Aa. Moreover, they suggested that the VDR gene polymorphism may affect parathyroid responsiveness to changes in [Ca2+]e, which in turn may influence onset and progression of hyperparathyroidism in ESRD patients.

Somatic mutations of the MEN1 gene and microsatellite instability in a case of tertiary hyperparathyroidism occurring during high phosphate therapy for acquired, hypophosphatemic osteomalacia

Somatic mutations of the MEN type 1 (MEN1) gene were recently shown to be responsible for tumorigenesis in 13-26% of sporadic, nonfamilial primary hyperparathyroidism. However, it is unknown whether these mutations are also involved in tumorigenesis of parathyroid glands occurring during high phosphate therapy for hypophosphatemic rickets or osteomalacia. A male patient with adult-onset, hypophosphatemic osteomalacia had been treated with 1alpha-OHD3 and oral phosphate for 13 yr when tertiary hyperparathyroidism developed. After total resection of four enlarged parathyroid glands and autotransplantation of a hyperplastic gland, the patient has continued to do well for the last 2 yr. Sequence analysis of the coding exons of MEN1 gene revealed a 36-bp deletion with a 2-bp insertion (exon 2) in the right upper parathyroid gland accompanied with loss of heterozygosity at 11q13 locus and a heterozygous mutation of 2-bp deletion (AG) in exon 10 in the right lower gland, in which microsatellite instability was also found. No MEN1 gene mutation was detected in the other two hyperplastic parathyroid glands or in the peripheral blood. These findings indicate that MEN1 gene mutations contributed to tumorigenesis of the right upper parathyroid gland in this case of phosphate-induced tertiary hyperparathyroidism. Very recently a bone tumor was found in the right femoral neck, and the tumor (chondroblastoma) was resected.

Electron microscopic observation of established chondrocytes derived from human intervertebral disc hernia (KTN-1) and role of macrophages in spontaneous regression of degenerated tissues

BACKGROUND CONTEXT

Biological and pathological cell processes during the degeneration of intervertebral discs are as yet poorly understood.

PURPOSE

An electron microscope was used to observe disc hernia degeneration at the cellular level as expressed in extruded tissue from a human intervertebral disc and in cultured chondrocytes. The mechanism of spontaneous regression was analyzed in order to investigate the effects of homologous macrophages, and the results of this analysis may be developed into a clinical therapy.

STUDY DESIGN/SETTING

Extruded tissue specimens excised during surgery on human intervertebral disc hernia and cultured chondrocytes isolated from the excised tissue were observed by means of electron microscopy. Extracellular matrix metalloproteinase-3 (MMP-3) and its antagonist, tissue inhibitor of metalloproteinases-1 (TIMP-1), were observed by means of immune electron microscopy. Macrophages confirmed by CD68 immunostaining were added to the chondrocyte culture and observed by means of electron microscopy.

PATIENT SAMPLE

All control subjects and patients gave written consent to the study.

OUTCOME MEASURES

KTN-1 was directly observed without culture, and nuclei degeneration, the development of chromatin granules, changes in the osmotic pressure of the nuclear membrane and rough-surfaced endoplasmic reticulum, and the development of fat droplets were observed.

METHODS

Tissues excised during surgery were divided, a part of the tissues were fixed in various fixatives for electron microscopy and immune electron microscopy analysis, and the other part was treated with collagenase. In addition, chondrocytes were isolated and cultured. Human peripheral blood mononuclear cells were separated using the Ficoll method. After culturing the cells, macrophages were collected, added to the chondrocyte culture, and observed under an electron microscope. CD68 positivity of the macrophages was confirmed by CD68 immunostaining.

RESULTS

Freshly isolated chondrocytes in the hernia's extruded region differed markedly from cultured chondrocytes. By means of immunoelectron microscopy, MMP-3 and TIMP-1 were localized at the endoplasmic reticulum of the cultured chondrocytes. Infiltration of macrophages among the chondrocytes was observed in the mixed culture.

CONCLUSIONS

The tissue extruded from the intervertebral disc showed obvious signs of degeneration, such as changes in osmotic pressure. Macrophages were observed to be the mechanism of spontaneous regression.

Identification of Lck-derived peptides capable of inducing HLA-A2-restricted and tumor-specific CTLs in cancer patients with distant metastases

The Lck protein (p56(lck)), a src family tyrosine kinase essential for T cell development and function, is aberrantly expressed in various types of cancers. We revealed recently that Lck can be a tumor antigen recognized by HLA-A24-restricted and tumor-specific cytotoxic T lymphocytes (CTLs) of cancer patients with metastases. In this study, we tried to identify Lck-derived epitopes capable of inducing HLA-A2-restricted and tumor-specific CTLs in cancer patients. The tumor-infiltrating lymphocytes (TILs) from 2 HLA-A2 cancer patients were found to respond to COS-7 cells when co-transfected with the lck gene and either HLA-A0201, -A0206, or A0207 cDNA. These TILs contained CTLs capable of recognizing either the Lck(61-69), the Lck(246-254), or the Lck(422-430) peptide among 24 different peptides, all of which were prepared based on the HLA-A2 binding motif. Importantly, in vitro sensitization with the latter 2 peptides induced tumor-specific CTLs in HLA-A2(+) cancer patients with metastases, but not in those without metastases. Overall, the Lck(246-254) and Lck(422-430) peptides could be useful for specific immunotherapy of HLA-A2(+) cancer patients, especially with distant metastases.

marY2N, a LINE-like non-long terminal repeat (non-LTR) retroelement from the ectomycorrhizal homobasidiomycete Tricholoma matsutake

A LINE-like non-LTR retroelement designated marY2N was cloned from the ectomycorrhizal homobasidiomycete Tricholoma matsutake. marY2N has open reading frames that correspond to gag and pol, and a putative promoter and consensus sequences common to those of the mutators from fruit flies. While it is common to T. matsutake and Tricholoma magnivelare, marY2N does not reside in any other species of Tricholoma tested.

Multidrug resistance-associated protein 3 is a tumor rejection antigen recognized by HLA-A2402-restricted cytotoxic T lymphocytes

The identification of tumor rejection antigens recognized by CTLs and its application in peptide-based specific immunotherapy against melanomas have been extensively investigated in the past decade. However, only a small number of studies regarding these issues in other epithelial cancers have been reported. In this study, we show that a multidrug resistance-associated protein 3 (MRP3) is a tumor rejection antigen recognized by HLA-A2402-restricted CTLs established from T cells infiltrating into lung adenocarcinoma. MRP3 is expressed in differing quantities in tumor cells of various tissue types and origins. Four dominant MRP3-derived antigenic peptides that are recognized by the CTLs have been identified, each possessing in vitro immunogenicity. Namely, these four peptides (MRP3-503, MRP3-692, MRP3-765, and MRP3-1293) can induce peptide-specific CTLs after in vitro stimulation with these peptides in peripheral blood mononuclear cell cultures of HLA-A24(+) cancer patients, with the CTLs expressing cytotoxicity against HLA-A2402(+) MRP3(+) tumor cells but not against either HLA-A2402(-) or MRP3(-) target cells. The peptide specificity of the cytotoxicity of the CTLs was further confirmed by using peptide-loaded HLA-A24(+) EBV-transformed B cells. Widespread MRP3 expression in various tumor cell lines and tumor tissues at the mRNA level was confirmed. Furthermore, reactivities of the MRP3-peptide-induced CTLs against tumor cells correlated with MRP3 expression in the tumor cells. These results suggest that MRP3 and its derived peptides described in the present paper are potential candidates for cancer vaccines in regard to HLA-A24(+) patients with various tumors, particularly for those tumors that show anticancer drug resistance.

Binding of a SART3 tumor-rejection antigen to a pre-mRNA splicing factor RNPS1: a possible regulation of splicing by a complex formation

We recently reported the identification of a human SART3 gene that encodes a tumor-rejection antigen recognized by cytotoxic T lymphocytes (CTLs). The squamous-cell carcinoma antigen recognized by T cells-3 (SART3) is an RNA-binding protein expressed in the nucleus of the majority of proliferating cells, including normal cells and malignant cells, but not in normal tissues except for the testes and fetal liver. To determine its biologic function, we employed a 2-hybrid screening in yeast for proteins interacting with SART3, and this method yielded a pre-mRNA splicing factor (RNA-binding protein prevalent during the S phase or RNA-binding protein with a serine-rich domain [RNPS1]) that activated both constitutive and alternative splicing of pre-mRNA in vitro. Interaction of SART3 with RNPS1 through the physical association of N-terminal domains of RNPS1 was confirmed by both in vitro pull-down assay and immunoprecipitation assay. Cotransfection of the 2 genes changed the distribution pattern of SART3 from diffuse nucleoplasmic spreading to nuclear speckled regions in which the RNPS1 was colocalized, suggesting a complex formation of the 2 proteins. In cooperation with RNPS1, SART3 stimulated the proximal alternative 3' splicing of a calcitonin-dihydrofolate reductase chimeric minigene pre-mRNA. These results suggest that SART3 is involved in the regulation of mRNA splicing probably via its complex formation with RNPS1.

Vascular endothelial dysfunction resulting from L-arginine deficiency in a patient with lysinuric protein intolerance

Although L-arginine is the only substrate for nitric oxide (NO) production, no studies have yet been reported on the effect of an L-arginine deficiency on vascular function in humans. Lysinuric protein intolerance (LPI) is a rare autosomal recessive defect of dibasic amino acid transport caused by mutations in the SLC7A7 gene, resulting in an L-arginine deficiency. Vascular endothelial function was examined in an LPI patient who was shown to be a compound heterozygote for two mutations in the gene (5.3-kbp Alu-mediated deletion, IVS3+1G-->A). The lumen diameter of the brachial artery was measured in this patient and in healthy controls at rest, during reactive hyperemia (endothelium-dependent vasodilation [EDV]), and after sublingual nitroglycerin administration (endothelium-independent vasodilation [EIV]) using ultrasonography. Both EDV and NO(x) concentrations were markedly reduced in the patient compared with those for the controls. They became normal after an L-arginine infusion. EIV was not significantly different between the patient and controls. Positron emission tomography of the heart and a treadmill test revealed ischemic changes in the patient, which were improved by the L-arginine infusion. Thus, in the LPI patient, L-arginine deficiency caused vascular endothelial dysfunction via a decrease in NO production.

Detection of B virus antibody in monkey sera using glycoprotein D expressed in mammalian cells

The gene encoding glycoprotein D (gD) of the monkey B virus (Cercopithecine herpesvirus 1) was cloned into a mammalian expression vector, pcDNA3.1(-), and the recombinant plasmid DNA was transfected into COS7 cells. The expression of gD in transfected COS7 cells was detected by indirect immunofluorescence assay or radioimmunoprecipitation analysis (RIPA). Although the expressed gD protein was revealed to react well with sera from monkeys naturally infected with B virus by RIPA, some sera showed reduced reactivity when analyzed by the Western blotting (WB) method. Some sera also showed relatively high background when the WB was performed using gD expressed from recombinant plasmid. The mutant gD protein lacking the transmembrane domain (TM) and cytoplasmic tail (CT) was next expressed in COS7 cells. The mutant protein was secreted into culture medium without apparent loss of the antigenicity. Using the secretory form of the gD protein as antigen in dot blot analysis, sera from B virus-infected monkeys were shown to react with the mutant protein without nonspecific reaction. Since the recombinant gD or its derivative lacking TM and CT could be expressed in mammalian cells with proper antigenicity, these antigens appeared to be useful for serological detection of B virus infection in monkeys.