Immunological analysis of pulmonary hypertension in connective tissue diseases

OBJECTIVE

To analyze the immunological characteristics of the sera of patients with inflammatory connective tissue diseases complicated by pulmonary hypertension (PH).

METHODS

Sera of 24 patients with mixed connective tissue disease complicated by PH (MCTD-PH), sera of 11 patients with other connective tissue diseases complicated by PH (Other-PH; 6 systemic sclerosis, 3 systemic lupus erythematosus, 2 rheumatoid arthritis), and sera of 15 patients with MCTD not complicated by PH (MCTD-non-PH) were tested for IgG antibodies against U1RNP proteins, U1RNP-70K protein, U1RNP-A protein, and U1RNP-C protein, and for IgG and IgM antibodies to beta2-glycoprotein I dependent cardiolipin (CL) and human umbilical vein endothelial cells. We also measured the serum levels of von Willebrand factor related antigens and interleukin 6 (IL-6).

RESULTS

(1) The titers of the anti-U1RNP, anti-U1RNP-70K, anti-U1RNP-A, and anti-U1RNP-C antibodies were significantly higher in the MCTD-PH and MCTD-non-PH groups than in the Other-PH group. However, there were no statistically significant differences in the titers of these 4 antibodies between the MCTD-PH and MCTD-non-PH groups. (2) The titers of the IgG aCL and the serum IL-6 levels were significantly higher in the MCTD-PH group than in the MCTD-non-PH group. (3) Statistically significant correlations between the anti-U1RNP and IgG anti-CL antibody titers, and between the IgG anti-endothelial cell and IgG anti-CL antibody titers were observed within the MCTD-PH and Other-PH groups, but not within the MCTD-non-PH group.

CONCLUSION

The occurrence of anti-U1RNP, anti-endothelial cell, and anti-CL antibodies is associated with PH in certain patients with connective tissue disease.

Site-directed mutagenesis of restriction endonuclease HindIII

Site-directed mutagenesis by inverse PCR was done on the HindIII gene. Target residues to be mutated were chosen according to (i) the fact that a mutant obtained by sodium nitrite treatment showed almost no HindIII activity, where Asp-123 was replaced with Asn, and (ii) the model proposed by Stahl et al. (Stahl, F., Wende, W., Jeltsch, A. and Pingoud, A. Biol. Chem. 379, 467-473 (1998)). Seven kinds of mutants were obtained by the PCR, and their enzymatic and biochemical properties were examined. Three mutants, P50S, D108L, and D123N, showed fairly low HindIII activity. On the other hand, the other four, P84Q, E86K, V106E, and K125N, retained the activity. In particular, E86K showed higher activity than the wild enzyme. This fact was confirmed when activities of the purified wild and E86K enzymes were assayed. These results coincided fairly well with data using E. coli strains that carry the respective mutant plasmids, on their resistance to phage T7 and on growth rate. We conclude that the PE motif at residues 50 and 51, and DXK motif at residues 108-110, are responsible for the enzymic reaction of HindIII.

[Churg-Strauss syndrome with pulmonary eosinophilia and intrapulmonary lymph nodes 2 years before the onset of vasculitis]

We report a case of a 55-year-old man who had been treated for bronchial asthma diagnosed at the age of 51. One year following diagnosis, chest X-ray films disclosed nodular shadows. Biopsy specimens obtained by video-assisted thoracoscopic surgery were histopathologically identified as intrapulmonary lymph nodes. Three years after the initial diagnosis, the patient experienced sensory disturbance of the lower extremities, low-grade fever, and weight loss. At this point he was admitted to our hospital. On admission, physical examination and clinical investigations showed peripheral eosinophilia and signs of vasculitis. Specimens obtained by transbronchial lung biopsy and bronchoalveolar lavage showed strong evidence of tissue damage with infiltration of eosinophils but no evidence of necrotizing vasculitis or extra-vascular granuloma. Churg-Strauss syndrome (CSS) was diagnosed, and treatment was initiated with prednisolone at a dose of 60 mg/day. Except for the sensory disturbances in the lower extremities, after a few days of treatment the patient's symptoms subsided and his clinical data improved. This case was clinically important because pulmonary eosinophilic infiltration into vessel walls was confirmed a year after the diagnosis of bronchial asthma, and 2 years before the patient demonstrated signs of vasculitis. Further, it was a very rare case of CSS in which intrapulmonary lymph nodes had developed beneath the visceral pleura despite the absence of a history of heavy smoking, thus suggesting continuous stimulation by some as yet unknown antigen.

Crystal structure of beta-amylase from Bacillus cereus var. mycoides at 2.2 A resolution

The crystal structure of beta-amylase from Bacillus cereus var. mycoides was determined by the multiple isomorphous replacement method. The structure was refined to a final R-factor of 0.186 for 102,807 independent reflections with F/sigma(F) > or = 2.0 at 2.2 A resolution with root-mean-square deviations from ideality in bond lengths, and bond angles of 0.014 A and 3.00 degrees, respectively. The asymmetric unit comprises four molecules exhibiting a dimer-of-dimers structure. The enzyme, however, acts as a monomer in solution. The beta-amylase molecule folds into three domains; the first one is the N-terminal catalytic domain with a (beta/alpha)8 barrel, the second one is the excursion part from the first one, and the third one is the C-terminal domain with two almost anti-parallel beta-sheets. The active site cleft, including two putative catalytic residues (Glu172 and Glu367), is located on the carboxyl side of the central beta-sheet in the (beta/alpha)8 barrel, as in most amylases. The active site structure of the enzyme resembles that of soybean beta-amylase with slight differences. One calcium ion is bound per molecule far from the active site. The C-terminal domain has a fold similar to the raw starch binding domains of cyclodextrin glycosyltransferase and glucoamylase.

Levels of IL-12 in the sera of patients with systemic lupus erythematosus (SLE)--relation to Th1- and Th2-derived cytokines

IL-12 is a cytokine that induces Th1-derived cytokines (interferon-gamma (IFN-gamma) and IL-2). The significance of IL-12 in human autoimmunity is no clear, and the serum levels of IL-12 in SLE are not clearly established. Therefore, we examined the levels of IL-12 in 39 patients with active SLE, with sandwich ELISA. The levels of IL-12 in patients were significantly higher than in normal subjects. Patients with high levels of IL-12 also had high levels of IFN-gamma, while their levels of IL-13 were significantly lower than in patients with normal levels of IL-12. Patients with pulmonary involvement had high levels of IL-12, and steroid therapy decreased the IL-12 level in three patients. In a retrospective study of seven patients, various changes of IL-12 and IL-13 were recognized before disease flare. Thus, in SLE patients, the level of IL-12 was increased and this increase was related to the change of Th1- or Th2-derived cytokines with some organ involvement.

A critical evaluation of enzyme immunoassays for detection of antinuclear autoantibodies of defined specificities. I. Precision, sensitivity, and specificity

OBJECTIVE

To determine the performance characteristics of enzyme-based immunoassay (EIA) kits for the detection of antinuclear and other autoantibodies of defined specificities.

METHODS

Nine manufacturers of EIA kits to detect antibodies of defined specificities participated in a study in which they received coded sera from the Centers for Disease Control and Prevention. These coded sera contained different dilutions of antibody of one specificity mixed with sera containing antibodies of other specificities. The manufacturers were asked to use their standard technology to determine antibody content and send the data to a committee of the International Union of Immunological Societies for analysis. The data were analyzed for sensitivity and specificity in the detection of anti-double-stranded DNA (anti-dsDNA), anti-single-stranded DNA, antihistone, anti-Sm, anti-U1 RNP, anti-SSA/Ro, anti-SSB/La, anti-Scl-70 (DNA topoisomerase I), anticentromere, and anti-Jo-1 antibodies. In addition, replicate samples were included in the coded sera to evaluate the precision of each EIA method.

RESULTS

Lack of sensitivity and specificity was most evident in the anti-dsDNA and anti-Sm kits, although 2 kits for anti-dsDNA achieved acceptable sensitivity and specificity. Generally, anti-SSA/Ro, anti-SSB/La, anti-Scl-70, anticentromere, and anti-Jo-1 kits performed well. Many false-positive results were obtained with a multiple myeloma serum containing cryoprecipitates, but multiple myeloma sera without cryoprecipitates presented no problem in the EIA system. Precision, based on evaluation of replicate samples, varied from very good to poor.

CONCLUSION

No single manufacturer was clearly superior to others in terms of their products' overall sensitivity, specificity, and precision. Areas that needed improvement were in kits for the detection of antibodies to dsDNA and to Sm antigen. Some EIA kits achieved good sensitivity and specificity. Individual manufacturers were informed of the performance of their respective kits so they could take measures to correct perceived deficiencies and thus improve the reliability of a group of important diagnostic assays used in the evaluation of systemic rheumatic diseases.

Intracellular redistribution of truncated La protein produced by poliovirus 3Cpro-mediated cleavage

The La autoantigen (also known as SS-B), a cellular RNA binding protein, may shuttle between the nucleus and cytoplasm, but it is mainly located in the nucleus. La protein is redistributed to the cytoplasm after poliovirus infection. An in vitro translation study demonstrated that La protein stimulated the internal initiation of poliovirus translation. In the present study, a part of the La protein was shown to be cleaved in poliovirus-infected HeLa cells, and this cleavage appeared to be mediated by poliovirus-specific protease 3C (3Cpro). Truncated La protein (dl-La) was produced in vitro from recombinant La protein by cleavage with purified 3Cpro at only one Gln358-Gly359 peptide bond in the 408-amino-acid (aa) sequence of La protein. The dl-La expressed in L cells was detected in the cytoplasm. However, green fluorescence protein linked to the C-terminal 50-aa sequence of La protein was localized in the nucleus, suggesting that this C-terminal region contributes to the steady-state nuclear localization of the intact La protein in uninfected cells. The dl-La retained the enhancing activity of translation initiation driven by poliovirus RNA in rabbit reticulocyte lysates. These results suggest that La protein is cleaved by 3Cpro in the course of poliovirus infection and that the dl-La is redistributed to the cytoplasm. dl-La, as well as La protein, may play a role in stimulating the internal initiation of poliovirus translation in the cytoplasm.

Circulating levels of beta-chemokines in systemic lupus erythematosus

OBJECTIVE

Recent evidence suggests the role of beta-chemokines and their receptors in human immunodeficiency virus infection. We examined the serum levels of beta-chemokines in patients with systemic lupus erythematosus (SLE).

METHODS

The serum levels of beta-chemokines, macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, RANTES, and monocyte chemoattractant protein-1 (MCP-1) in patients with SLE were determined by ELISA.

RESULTS

There were significant differences between the patients with SLE and healthy controls in the serum concentrations of RANTES (p < 0.001) and MCP-1 (p < 0.01), but not MIP-1alpha (p = 0.07) and MIP-1beta (p = 0.68). A decrease of RANTES and an increase of MCP-1 was observed with the progression of disease activity in the patients with SLE.

CONCLUSION

Changes in the serum levels of RANTES and MCP-1 may indicate an interaction between SLE disease activity and the production of beta-chemokines.

Repair of the mandibular nerve by autogenous grafting after ablative surgery of the mandible

In this paper, we introduce our original method of autologous nerve grafting for substitution of the mandibular nerve after mandibular resection in three subjects. The lateral cutaneous nerve of the forearm served as a donor nerve, and the graft was imbedded microsurgically at the junctures using an epineurial nerve suture technique. Oversized grafts were chosen in order to insert them without tension in a space between the stumps of the recipient nerve and the regeneration zone of the bone. In all three subjects, sensibility of the lower lip and chin recovered completely after about ten months.

[Chlamydia-induced reactive arthritis--HLA-B 27 negative two patients]

Two cases with HLA-B 27 negative, Chlamydia-induced reactive arthritis (ReA) were described. Case 1: A 30 y.o. male developed balanitis, urethritis, arthritis of both knees, elbows, shoulders and hip joints on May in 1997. Laboratory findings revealed CRP 2.7 mg/dl (normal range < 0.3), ESR 33 mm/h and negative rheumatoid factor (RF) test. Anti-Chlamydia trachomatis antibodies, IgG 2.22, IgA 3.33 were positive. HLA-typing revealed A 2, A 24 (9), B 39 (16), B 52 (5). He was diagnosed as ReA and arthritis subsided with treatment of minocycline and nonsteroidal antiinflammatory drugs (NSAIDs). Case 2: A 40 y.o. Iranian American male developed balanitis, urethritis, lumbago, arthritis of both elbows, knees and foot joints, iridocyclitis on August in 1995. Chlamydia trachomatis was detected in the urethral swab culture. He was diagnosed as ReA and treated with minocycline and NSAIDs. He was referred to our hospital on June in 1996. Arthritis at both knees and feet was detected. Laboratory findings revealed CRP 0.8 mg/dl, negative RF test was revealed. Antibodies to Chlamydia were positive (IgG 1.49, IgA 1.53) positive. HLA typing revealed A 1, A 2, B 37, B 55 (22). He was again treated with minocycline and NSAIDs and ReA ameliorated. Since HLA-B 22, B 37 and B 39 have been reported to cross-react or to have homology with B 27, B 22, B 37 and B 39 are likely to related to inducing ReA.

[Plasmapheresis for collagen diseases]

Recently plasmapheresis has been performed for connective tissue disease. Double-filtration plasmapheresis (DFPP) has mainly been performed for rheumatoid arthritis (RA) and systemic lupus erythematosus (SEL) since 1980. In DFPP, autoantibodies and immune complex are removed by the second filter. The adaptation of plasmapheresis is commonly for cases (1) which are resistant to some medications, (2) which have a high titer of antibodies or immune complex, (3) in which the medication must be decreased or stopped because of side effects and complications, or (4) which are in the acute active phase. We suggest DFPP to be useful as a treatment for connective tissue disease.

Expression of CD80 and CD86 on peripheral blood T lymphocytes in patients with systemic lupus erythematosus

CD80 and CD86 were detected in high amounts on circulating T cells in the peripheral blood of some patients with systemic lupus erythematosus (SLE), using flow cytometry and monoclonal antibodies. Patients with other connective tissue diseases did not have a high percentage of T cells expressing CD80 or CD86 in their peripheral blood. CD80 was expressed mainly on CD4 T cells, whereas CD86 was expressed on CD8 T cells, and these two populations were associated with particular clinical features. These two molecules were expressed on different T-cell populations and might have different roles in the generation and regulation of immune responses. Since high expression of CD86 on T cells was detected much earlier than the appearance of clinical features and a high titer of anti-DNA antibody, it may be a useful parameter for predicting the flare of SLE.

Circulating interleukin-16 in systemic lupus erythematosus

OBJECTIVE

To investigate the relationship between interleukin (IL)-16 and systemic lupus erythematosus (SLE).

METHODS

Serum levels of IL-16 were examined in SLE patients using an enzyme-linked immunosorbent assay (ELISA).

RESULTS

The serum level of IL-16 in the patients was much higher than that in healthy volunteers (P < 0.001). An increase in IL-16 was observed in proportion to the activity of SLE assessed by the SLE Disease Activity Index (SLEDAI) score (P < 0.0001).

CONCLUSIONS

Our observations suggest an interaction between disease activity and the production of IL-16 in SLE, and reveal that IL-16 is a useful indicator of disease activity. This is the first report describing the relationship between IL-16 and SLE.

Discrimination of productive and non-productive cough by sound analysis

There are two types of coughs, productive and non-productive; the former is caused by excess airway secretions. The analysis of cough may provide important clues not only to aid diagnosis, but also for the selection of drugs for treatment. In this study, cough sounds recorded in a free acoustic field from patients with productive cough and non-productive cough due to chronic airway diseases were compared with those of voluntary cough of healthy subjects and were analyzed by sound spectrogram and time-expanded waveform. All cough sounds could be separated into two or three phases. The implementation of the novel technique to record cough sounds in the free acoustic field and to analyze the sounds of the high frequency range enable recognition of the characteristics of the cough sounds in phase 2 of the cough.

Ischemic preconditioning suppresses the noradrenaline turnover in the rat heart

OBJECTIVE

The mechanism by which ischemic preconditioning protects the heart is presumed to be related to the reduction of energy consumption during a subsequent myocardial infarction. Since the sympathetic nervous system enhances cardiac function and energy consumption, we investigated the relation between ischemic preconditioning and the turnover rate of noradrenaline (NA) in the rat heart.

METHODS

The effect of 3 cycles of 5-min occlusions of the rat left coronary artery on changes in arterial blood pressure and heart rate provoked by a subsequent 30 min of ischemia were examined until 60 min after reperfusion. The effect of 3 cycles of occlusions on the infarct size was also evaluated 60 min after reperfusion by comparing the infarcted area with the area at risk in these animals (6 per preconditioned and sham-operated group). The tissue concentration of NA during sustained ischemia was determined in the left ventricle, the intraventricular septum, and the right ventricle in the preconditioned and sham-operated groups. Changes in the turnover rate of NA after 3 cycles of occlusions were also evaluated by assessing the alpha-methyl-p-tyrosine-induced depletion of NA (n = 7 per group).

RESULTS

A series of transient occlusions reduced the infarct size 60 min after a sustained ischemia for 30 min. Arterial pressure and heart rate were not affected. The concentration of NA was decreased in the left ventricle 60 min after the onset of sustained ischemia in both the preconditioned and sham-operated groups. The treatment with alpha-methyl-p-tyrosine decreased the NA concentration in all regions of the heart in the sham-operated group after 60 min. However, the treatment with alpha-methyl-p-tyrosine did not deplete the NA concentration in both the occluded and nonoccluded regions in the preconditioned group.

CONCLUSIONS

Transient ischemia ameliorated the heart injury induced by a subsequent sustained ischemia, as assessed histologically. The activity of the sympathetic nervous system in all regions of the heart was reduced by transient ischemia in the left coronary vascular bed. These findings suggest that the inhibition of the sympathetic nervous system by the treatment of ischemic preconditioning takes part in the cardiac protection.

A clinical analysis of the recovery from sensory disturbance after sagittal splitting ramus osteotomy using a Semmes-Weinstein pressure aesthesiometer

A number of studies of evaluation methods for sensory disturbance after sagittal splitting ramus osteotomy (SSRO) are known. To compare postoperative sensory disturbances among patients in different hospitals, a highly reproducible and standardized sensory test is required. In the present study, we measured the tactile threshold in the region innervated by the mental nerves in 45 patients (90 sides) after SSRO using a Semmes-Weinstein pressure aesthesiometer. The percentage of recovery to the normal level defined by Bell was 72.2% at one week, 82.2% at 4 weeks, and 90.0% at 8 weeks after SSRO. The recovery process was evaluated by classifying the postoperative sensory disturbance into 5 grade levels according to Bell's interpretation scale. The results showed that the SW sensory test is useful for evaluation of the recovery process from sensory disturbance after SSRO. Some improvements of this test were also discussed.

Central island tongue flap

Pedicled tongue flaps have proved to be an effective method of repairing defects due to tissue loss in the oral cavity. Their central position, mobility, and excellent blood supply make their use feasible in a variety of sites. This paper describes the use and applications of central island tongue flaps to reconstruct defects of anterior floor of the mouth. This procedure was conducted at the Department of Oral and Maxillofacial Surgery, Medical University Hanover, introducing an improved surgical method and presenting the actual operation performed in our department. This method is considered superior for resurfacing the anterior floor of mouth defects because it is easy to perform and results in recovery of function and cosmetics.

HLA-DRB1 alleles and beta 2 glycoprotein I-dependent anticardiolipin antibodies in Japanese patients with systemic lupus erythematosus

OBJECTIVE

To investigate the association of HLA DRB1 alleles with beta 2 glycoprotein I (beta 2 GPI)-dependent anticardiolipin antibodies (aCL) in Japanese patients with systemic lupus erythematosus (SLE).

METHODS

One hundred and forty-five Japanese patients with SLE were studied. beta 2 GPI-dependent aCL was measured by enzyme-linked immunosorbent assays. DNA typing of the DRB1 alleles was performed by the polymerase chain reaction sequence specific oligonucleotide probe method.

RESULTS

beta 2 GPI-dependent aCL was positive in 29 (20.0%) out of 145 SLE patients. SLE patients with beta 2 GPI-dependent aCL had a significantly higher frequency or one or more of the clinical manifestations assumed to be associated with aCL, compared to those without beta 2 GPI-dependent aCL (p < 0.05). The frequency of DRB1*0901 was lower in SLE patients than in healthy subjects. SLE patients with beta 2 GPI-dependent aCL were significantly associated with DRB1*0901 as compared to those without beta 2 GPI-dependent aCL (41.4% vs 15.5%, p < 0.005, R.R. = 3.8), although the corrected P value was not significant.

CONCLUSION

A possible association of DRB1*0901 with Japanese SLE patients with beta 2 GPI-dependent aCL was found. This association indicates an association between the disease and the HLA-DR53 (DRB4)-bearing haplotypes in different ethnic groups.

Expression of costimulatory molecule CD80 on peripheral blood T cells in patients with systemic lupus erythematosus

OBJECTIVE

To investigate the expression of costimulatory molecule CD80 on T cells of peripheral blood mononuclear cells (PBMC) in patients with systemic lupus erythematosus (SLE).

METHODS

Monoclonal antibodies against CD80 were used for flow cytometry and expression of CD80 on PBMC was studied in 26 patients with SLE, 18 patients with rheumatoid arthritis (RA), 8 patients with mixed connective tissue disease (MCTD), and 22 healthy controls.

RESULTS

CD80 was detected on CD3+ and CD19+ cells in patients with SLE and it was significantly higher than that of controls. In patients with SLE CD80 was expressed on CD4+ T cells (8.05+/-5.45%), significantly higher than in RA and controls, but was not highly expressed on CD8+ T cells (1.67+/-2.87%). CD80+CD4+ T cell phenotype analysis revealed CD45RA-, CD45RO+, and CD25+, or HLA-DR+ activated T cells. The percentage of CD80+ cells in CD4+ cells increased in the active stage of SLE, and was significantly correlated with the SLE disease activity index.

CONCLUSION

CD80 can be expressed on activated CD4+ T cells in PBMC of patients with SLE in vivo and the appearance of these cells is associated with the disease activity in SLE.