Serum albumin metabolism in rheumatic diseases: relationship to corticosteroids and peptic ulcer

Serum albumin concentrations and albumin metabolism were assessed in 150 patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and healthy subjects. Hypoalbuminemia was more marked in RA patients than in SLE patients. There was no correlation in RA patients between albumin levels and either disease activity or glucocorticosteroid administration; however, hypoalbuminemia in RA patients significantly correlated with juxta-articular erosions or with the incidence of peptic ulcer. The incidence of peptic ulcer was higher in RA patients with the combination of hypoalbuminemia and corticoid therapy, and reduced by the injection of anabolic steroid. In contrast, anabolic steroid did not improve hypoalbuminemia and bony erosions in the patients. The fractional catabolic rate of albumin was similarly elevated in both RA and SLE, while the absolute catabolic rate was increased to a greater extent in SLE patients. This explains the differences in serum albumin concentration between the patients with RA and SLE.

Hyperreactivity of activated B cells to B cell growth factor in patients with systemic lupus erythematosus

Inasmuch as B cell function is in large part determined by lymphokine-derived accessory signals, we studied the effects of recombinant IL-2 and low-molecular-weight B cell growth factor (BCGF) on peripheral blood B cells activated with Staphylococcus aureus Cowan I to explain the B cell hyperfunction in patients with SLE. When S. aureus Cowan I-activated normal B cells were separated into Tac-antigen (Tac-Ag)+ and Tac-Ag- cells by employing a rosette technique, IL-2 induced only the Tac-Ag+ cells to proliferate, whereas both the Tac-Ag+ and Tac-Ag- cells responded to BCGF. The Tac-Ag+ and Tac-Ag- fractions of activated SLE B cells behaved like respective fractions of activated normal B cells for the pattern of response to these growth factors. It should be pointed out, however, that although the Tac-Ag+ B cells of SLE patients and those of normal controls responded to IL-2 to almost the same degree, both the Tac-Ag+ and Tac-Ag- B cells of SLE patients exhibited markedly enhanced proliferative responses to BCGF. The selectively enhanced responsiveness of a broader range of activated SLE B cells may lead to B cell hyperactivity in this disease.

Hyperreactivity of activated B cells to B cell growth factor in patients with systemic lupus erythematosus

Inasmuch as B cell function is in large part determined by lymphokine-derived accessory signals, we studied the effects of recombinant IL-2 and low-molecular-weight B cell growth factor (BCGF) on peripheral blood B cells activated with Staphylococcus aureus Cowan I to explain the B cell hyperfunction in patients with SLE. When S. aureus Cowan I-activated normal B cells were separated into Tac-antigen (Tac-Ag)+ and Tac-Ag- cells by employing a rosette technique, IL-2 induced only the Tac-Ag+ cells to proliferate, whereas both the Tac-Ag+ and Tac-Ag- cells responded to BCGF. The Tac-Ag+ and Tac-Ag- fractions of activated SLE B cells behaved like respective fractions of activated normal B cells for the pattern of response to these growth factors. It should be pointed out, however, that although the Tac-Ag+ B cells of SLE patients and those of normal controls responded to IL-2 to almost the same degree, both the Tac-Ag+ and Tac-Ag- B cells of SLE patients exhibited markedly enhanced proliferative responses to BCGF. The selectively enhanced responsiveness of a broader range of activated SLE B cells may lead to B cell hyperactivity in this disease.

Familial occurrence of impaired interleukin-2 activity and increased peripheral blood B cells actively secreting immunoglobulins in systemic lupus erythematosus

PURPOSE

We tested the hypothesis that some abnormalities of immune functions are genetically controlled in patients with systemic lupus erythematosus (SLE).

SUBJECTS AND METHODS

We used a phytohemagglutinin-induced interleukin-2 (IL-2) activity assay and a spontaneous plaque-forming cell assay to evaluate T-cell and B-cell function, respectively, in 34 clinically healthy family members of six SLE probands.

RESULTS

Impaired IL-2 activity was found in 15 of the 29 consanguineous relatives. There was no relation between the household relatives and the nonhousehold relatives; none of the five nonconsanguineous household persons had abnormal results. Results for the B-cell assay were abnormal in 22 of the 29 consanguineous relatives. The B-cell abnormalities were more commonly observed in the consanguineous household relatives; four of the five nonconsanguineous household relatives also had abnormal assay results.

CONCLUSION

The findings indicate that the impaired IL-2 activity in relatives appears to strongly correlate with a genetic relationship. Although the evidence favors a genetic basis for the B-cell abnormalities, environmental effects may also contribute to the familial occurrence of these abnormalities.

[A double blind trial of alfacalcidol on patients with rheumatoid arthritis (RA)]

A double blind comparative trial was performed in order to study the efficacy and safety of alfacalcidol (1 alpha-OH-D3) in a total of 140 patients with RA admitted to 31 institutes, using a placebo as the control. The treatment period was 16 weeks. The doses of 1 alpha-OH-D3 were 1.0 microgram/day and 2.0 micrograms/day. It was permissible to use non-steroid anti-inflammatory drugs for basic treatment and oral steroidal preparations for maintenance treatment without changing the doses of these drugs during the study period in patients who had been treated with them before participating in the study (for oral steroidal preparations, the dose was limited to 5 mg/day or less as prednisolone). The percentage of patients with slight improvement was about 10% higher in 1 alpha-OH-D3 groups than in placebo group, but the difference between them was not significant. The results tended to be better in the treated groups than in the placebo group, but there was no significant difference between them with regard to duration of morning stiffness, number of joints with pain, number of joints with swelling and Lansbury's index. The effects of 1 alpha-OH-D3 on various immunological parameters including lymphocyte subsets were not clearly demonstrated. However, interestingly, the ratio of OKT-4/OKT-8 was found not to change in patients whose initial value was normal, while it tended to decrease after 1 alpha-OH-D3 treatment in patients whose initial value was abnormally high. The improvement of bone atrophy was judged by microdensitometry (MD) method using X-ray picture of hands. The indexes of bone density (GS max, GS min and sigma GS/D) demonstrated that 1 alpha-OH-D3 prevents reduction in bone density. 1 alpha-OH-D3 did not trigger hypercalcemia in any case. However there was a slight but significant increase of serum Ca value in the group with higher dose (2.0 micrograms/day). Taking the efficacy into consideration, the dose of 1.0 microgram/day was judged to be suitable for long-term treatment.

Effects of an antithrombotic agent (MD-805) on progressing cerebral thrombosis

The effects of the newly developed synthetic selective antithrombin agent MD-805 were examined in 11 patients with progressing cerebral thrombosis, as an open trial. Nine (82%) of 11 patients improved after 1 week of intravenous drip infusion. No hemorrhagic complications were observed during the therapy. These results suggest that MD-805 is a safe and effective agent for treatment of progressing cerebral thrombosis.

Correlation between carotid blood flow and brain atrophy in patients with multi-infarct dementia

The relation between carotid blood flow measured by Doppler spectrum analysis and brain atrophy on computed tomography (CT) was studied in 22 subjects with multiple lacunar cerebral infarctions. The subjects were divided into two groups, 7 patients with multi-infarct dementia (MID) (mean age 73 years) and 15 nondemented lacunar stroke subjects (NDLS) (mean age 66 years), according to DSM III criteria. All subjects had a score of 7 points or more on Hachinski's ischemic score and showed no carotid artery stenosis. Systolic peak frequency of the common carotid artery (CCA) was measured by Doppler spectrum analysis (Angioscan II). Brain atrophy was measured quantitatively on CT images by two-dimensional measurement using a digitizer. Peak frequencies were lower in MID than in NDLS. Brain atrophy was more severe in MID than in NDLS. There was a significant correlation between peak frequencies and brain atrophy in all subjects. These results indicate that CCA blood flow may reflect brain function in patients with multiple lacunar infarctions.

Effect of long-term administration of buflomedil on regional cerebral blood flow in chronic cerebral infarction

The influence of long-term oral administration of buflomedil on regional cerebral blood flow was investigated in 10 patients with chronic cerebral infarction and mild to moderate mental deterioration. Patients were given 150 mg buflomedil three times daily for a period of eight weeks. Regional cerebral blood flow (rCBF) was measured in patients before they began buflomedil treatment and during the last week of treatment. The interval of the rCBF measurements in the control subjects (n = 12) ranged from seven to forty-eight days. Mental function in the patients studied was evaluated by use of Hasegawa's simple intelligence scale for the aged and Zung's self-rating depression scale, before and during the last week of buflomedil treatment. The results showed a mean increase in rCBF of 10.5% +/- 12.1% in the patient group. The control group demonstrated virtually no change in rCBF measurements. Improvements in the mental function scores of the buflomedil-treated group were noted, and 5 of the 10 patients reported improvement in subjective symptoms.

Mode of action of monoclonal-nonspecific suppressor factor (MNSF) produced by murine hybridoma

Monoclonal-nonspecific suppressor factor (MNSF), a product of murine T cell hybridoma, suppresses antibody response to lipopolysaccharide. In an attempt to clarify the functional mechanisms in vitro, we investigated the mode of action of MNSF. This factor inhibited the antibody response by B cells (depleting T cells and Mø), thereby indicating that the lymphokine acts directly on B cells, without interaction between B and T cells or Mø. MNSF activity was absorbed by mitogen-stimulated T or B cells, but not by resting lymphocytes. Proliferative responses to T cell and B cell mitogens were inhibited dose dependently by the addition of MNSF. Kinetic studies showed that MNSF suppressed the antibody response, in all culture periods, thereby indicating that immunoglobulin secretion and proliferation were inhibited. The effect of growth factor on MNSF-mediated suppression was investigated to search for a possible suppression of MNSF action. Interleukin 2 (IL-2) remarkably inhibited MNSF activity, and the effect of IL-1 or IL-4 was less. IL-2 was most effective when added on the fourth day of culture. MNSF also inhibits division in the plasmacytoma line MOPC-31C or in thymoma EL4, but not in L929 fibroblasts. Tumor necrosis factor (TNF) inhibits cell division of various tumor cells and suppresses the pokeweed mitogen-induced antibody response, without cytotoxic action, as does MNSF. While MNSF and TNF have similar biochemical and physiochemical properties, the cross-reaction tests showed that both are antigenically discrete lymphokines. Although MNSF lacks TNF activity, the concomitant addition of both factors to L929 increases the cytotoxic action, a finding indicative of a synergistic effect.

Participation of suppressor-inducer cells in the suppression of adjuvant arthritis by transfer of spleen cells expanded by T cell growth factor

We attempted to elucidate the mechanism of action of T cell growth factor (TCGF)-expanded cells after stimulation with concanavalin A (Con A), a process which reduces the severity of adjuvant arthritis (AA), as seen in transferred syngeneic rats. TCGF-expanded cells were fractionated by Percoll density gradient or by the panning method, before the transfer. Transfer of cells with a density of between 1070 and 1079 suppressed AA most effectively, compared with other fractions with a density of less than 1070. A large number of the cells with density 1070-1079 were of the W3/25 phenotype. The transfer of W3/25 positive cells obtained by the panning method from TCGF-expanded cells reduced AA but not W3/25 negative cells. The suppressor function of TCGF-expanded cells was examined in an assay system in vitro. The addition of Con A-stimulated cells to the assay culture (but not expanded with TCGF), suppressed both the proliferation of spleen cells stimulated with Con A and the IgG production stimulated with lipopolysaccharide. The addition of TCGF-expanded cells to the assay culture had no effect on these responses. Thus, the W3/25 cells in the TCGF-expanded cells seem to function as suppressor-inducer cells, affect the presuppressor cells of the recipient rat and differentiate to suppressor effector cells.

Effect of aging on collateral circulation via pial anastomoses in cats

The effect of aging on collateral circulation via pial anastomoses after middle cerebral artery occlusion was investigated in young and aged cats. The reduction of blood flow and electroencephalography power were greater and collateral vessel resistance was higher in the aged group than the young group. Electroencephalography power after the occlusion was correlated with collateral resistance and blood flow in the two groups. These results suggest that collateral function deteriorates with aging and the high vulnerability to ischemic insult in aged brain may be caused in part by the poor collateral function.

Effect of smoking on regional cerebral blood flow in the normal aged volunteers

The effects of long-term cigarette smoking on regional cerebral blood flow (rCBF) were studied in 67 normal male volunteers. All subjects were healthy volunteers without any past history of cerebral and pulmonary disease. rCBF decreased significantly with advancing age. Although there was no significant difference in rCBF between young smokers and nonsmokers, elderly smokers showed significantly lower rCBF than elderly nonsmokers. There was no difference in vital capacity and FEV 1.0% between smokers and nonsmokers in both young and elderly groups. The smokers, however, showed significantly lower V50 than the nonsmokers. PeCO2 in smokers was significantly lower than in nonsmokers. No significant differences were seen in hematocrit, antithrombin III, aggregating platelet, serum lipids and blood pressure between smokers and nonsmokers in both age groups. There was a significantly positive correlation between rCBF and PeCO2 in all groups. These results suggest that long-term smoking may reduce rCBF by means of hypocapnia, resulting from latent small airway disturbances, not by advancing cerebral arteriosclerosis.

Effects of administration of dopamine and L-DOPA to dogs on their plasma level of dopamine sulfate

The effect of intravenous administration of dopamine (DA) or L-3,4-dihydroxyphenylalanine (L-DOPA), its immediate precursor, on the level of DA sulfate in dog plasma was examined, to clarify the source and physiological significance of DA sulfate which is present at high level in the plasma. After DA administration, the plasma level of free DA increased markedly, but the level of DA sulfate did not change. However, after administration of L-DOPA, the levels of both free DA and DA sulfate increased greatly. After a single injection of L-DOPA, increase in the level of free DA was transient, but that of DA sulfate persisted for a long time. These results suggest that some of the DA sulfate in dog plasma is formed from circulating L-DOPA, not from circulating DA, and that formation of DA conjugate may play a role in regulating the plasma level of free DA.

Characterization of monoclonal nonspecific suppressor factor (MNSF) with the use of a monoclonal antibody

The secretion of immunoglobulin (Ig) from cultured mononuclear cells by lipopolysaccharide (LPS) stimulation is inhibited by monoclonal nonspecific suppressor factor (MNSF), a lymphokine produced by murine T cell hybridoma. In an attempt to develop a murine monoclonal antibody (MAb) with specific reactivity against MNSF, a cell fusion technique that incorporated immune murine splenocytes and HAT-sensitive murine myeloma cells was used. Cross-reactivity experiments confirmed that the MAb (MO6) does not bind to unrelated proteins such as bovine serum albumin, mouse IgG, and murine interferon-gamma (IFN-gamma). There are no effects when anti-IFN-gamma antibodies are used with MNSF. As far as biological activity is concerned, MO6 inhibits in vitro the activity of MNSF in terms of the Ig secretion from cultured lymphocytes. By using MO6, affinity chromatography and immunoblotting were performed. The MNSF on the SDS-PAGE showed a band with m.w. of approximately 70,000, indicating the formation of an aggregate in saline; but after treatment with 0.4 M pyridine-acetic acid buffer, separate bands of 24,000 and 16,000 daltons were evident. Therefore MO6 recognizes 70,000 and both 24,000 and 16,000 daltons. Thus we confirmed by using this MAb and affinity chromatography, the existence of human counterpart, human nonspecific suppressor factor (hNSF), in supernatant from concanavalin A-stimulated T cells. When hNSF was fractionated by high pressure liquid chromatography (HPLC), the activity was found in a region corresponding to 70,000 daltons. However, when fractionated in pyridine-acetic acid buffer, hNSF activity was distributed in a slightly wider range of 15,000 to 30,000 daltons. Physicochemical analysis showed that the purified hNSF is resistant to either heating at 56 degrees C or to 2-mercaptoethanol treatment; however, it is labile to acidification at pH 2.0 and is also sensitive to protease treatment, the characteristics of which were similar to those of murine MNSF. Thus MO6 was confirmed to be a pertinent tool for isolation of hNSF, as well as for murine MNSF.