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In 38C B lymphocytes the membrane form of IgM is displayed on the cell surface whereas the secretory form of IgM is degraded. In the EH cell line, a light chain-deficient variant of 38C cells, the mu heavy chains are partially assembled with surrogate light chains characteristic of pre-B cells. In these cells neither the membrane (microns) nor the secretory (microsecond) forms of the mu heavy chain reach their final destination, and both are rapidly degraded. The degradation of mu chains in EH cells, like that of microsecond in 38C cells, is nonlysosomal and occurs prior to the trans-Golgi. However, while microsecond degradation in 38C cells is inhibited by brefeldin A, in EH cells microsecond and micron are retained and degraded by a brefeldin A-insensitive mechanism. These results indicate that degradation in EH cells occurs within the endoplasmic reticulum, whereas degradation in 38C cells requires exit from this compartment. Thus, mu heavy chains can be degraded in multiple sites along the secretory pathway. The location of the degradation process is determined by the developmentally regulated assembly species of the mu chains with either "classical" or surrogate light chains.

We have measured interleukin-1 alpha (IL-1 alpha) and beta levels in nasal polyps (NP) from patients with chronic sinusitis (CS) in order to determine their significance in the pathogenesis of NP. NP in ten cases (five male and five female; age range, 17-63 years) were removed to separate mononuclear (M) and polymorphonuclear (PMN) fractions through Ficoll-Paque separation media. ELISA measurements of the M fraction showed that the mean value of IL-1 beta was 17.8 pg/ml per gram, which was significantly higher than that of IL-1 alpha (7.04 pg/ml per gram, P < 0.01, Wilcoxon test). In the PMN fraction, the mean value of IL-1 alpha was 8.79 pg/ml per gram and that of IL-beta was 7.85 pg/ml per gram, which was not significantly different. Mononuclear leukocytes, particularly activated monocytes, seem to be a major source of IL-1 in the NP taken from patients with CS.

Characterization of a membrane-IgM-negative variant cell line derived from the murine B-cell line 38C-13 revealed the absence of light chains and the presence of polypeptides with an apparent molecular size of 18 kDa and 14 kDa, previously denoted omega and iota and characteristic of pre-B cells. These polypeptides assemble with the mu chains into complexes with apparent molecular sizes of about 100 kDa and 200 kDa. It has been previously shown that light-chain-deficient variants of the 38C cell line undergo 'secondary' light chain rearrangements. It is suggested, therefore, that complexes of mu and the 'surrogate' light chains omega and iota play a role in this process. As these complexes do not reach the cell surface we would like to propose that the mechanism of secondary rearrangement is intracellularly controlled.

The present study assessed sympathetic function in viable infarcted areas of the myocardium following the onset of myocardial infarction. The subjects were 19 patients with myocardial infarction. After exercise on a bicycle ergometer, simultaneous SPECT with Tl-201 and I-123 MIBG was performed. The behavior of MIBG following exercise remains to be clarified, but in the present study MIBG provided images different from those obtained with Tl. While the redistribution of Tl in the infarcted area was observed in 8 of 19 patients, MIBG was absent in the infarcted area in both the initial and delayed scans. In the patient undergoing CABG, the infarcted area showed no MIBG despite the normal perfusion of Tl. The previous proposal that the redistribution of Tl indicates myocardial viability to some extent suggests that the sympathetic function of the area of the myocardium showing the redistribution of Tl decreases even though the area is viable. These findings indicate that after the onset of myocardial infarction, there is a denervated but viable area in the myocardium, despite the viability demonstrated by Tl imaging. They also indicate that concurrent myocardial imaging with MIBG is useful for the detection of such a myocardium.

Stunned myocardium of right ventricle was studied by radionuclide angiography (RNA) and Thallium myocardial scintigraphy (TL) in 39 patients with inferior myocardial infarction with and without right ventricular myocardial infarction (RVMI). RNA was performed within 1 week of the onset (acute phase) and after 1 month, when exercise cardiac scintigraphy (EX-TL) was also performed. The ejection fraction (EF) of each ventricle calculated from RNA and the phase and amplitude evaluated visually and quantitatively by Fourier analysis were compared between the acute phase and 1 month after the onset of myocardial infarction. The degree of visualization of right ventricle was examined in EX-TL 1 month after the onset. (1) In RNA obtained in the acute myocardial infarction, abnormalities in the right ventricle (delayed phase or low amplitude image) were observed in 18 (46%) but not in 21 (54%) of the 39 patients (N group). Of those 18 patients, the abnormalities in the right ventricle alleviated in 11 (RVMI-A group) but persisted in 7 (RVMI-B group) in RNA obtained 1 month after the onset. (2) In the acute phase, the right ventricular ejection fraction (RVEF) was 39.4 +/- 10.4% in N group, 30.8 +/- 5.3% in RVMI-A group, and 29.6 +/- 8.9% in RVMI-B group, with significant differences between N group and the other two groups (P less than 0.05) but no significant difference between RVMI-A and RVMI-B groups. (3) After 1 month, RVEF was 40.1 +/- 10.1% in N group, 42.2 +/- 8.4% in RVMI-A group, and 32.2 +/- 9.8% in RVMI-B group, being improved in RVMI-A group and showing a significant difference as compared with RVMI-B group (p less than 0.05). (4) In EX-TL of RVMI-A group, the right ventricle was visible although the uptake of TL was reduced in the entire right ventricle. In RVMI-B group, only part of the right ventricular free wall was visible with defects in the other areas of right ventricle. The sign of RVMI showed improvements in many of the patients after the acute phase, and their condition was considered to have been so-called stunned myocardium, which is a complex of symptoms of reversible myocardial ischemia, rather than RVMI.

Immunotherapy of a murine B-cell lymphoma by antibodies to idiotypic determinants of its IgM, resulted in surviving tumour-free mice. Several of these mice, however, did develop tumours a long time after the initial inoculation of the tumour cells, or upon rechallenge of the survivors with B-lymphoma cells. The presence of tumour cells during this long latent period may have been due to the development in the host of an anti-idiotype immune response. These late-developing tumours were detected by a radioimmunoassay and characterized by immunofluorescent staining and sodium dodecyl sulphate/polyacrylamide gel electrophoresis. Cells of some late-developing tumours lost the idiotype recognized by the antibodies used for the immunotherapy. Several of these tumours expressed IgM on the cell surface, while others did not, because of the absence of light chains. They were identical in the structure of their rearranged mu chain genes proving their derivation from the original inoculation. Cell lines obtained from the late-developing tumours differed in their tumorigenicity. The appearance of idiotype-negative tumour cells as a result of anti-idiotype immunotherapy has a great impact in our efforts to cure lymphoma by this modality.

Sensitive double antibody sandwich ELISA methods was developed in order to quantify immunoreactive neutrophil elastase (NE) levels in nasal secretions with chronic sinusitis (CS). Microwell plate as a solid phase was coated with anti-NE antibody. Two different horseradish peroxidase (HRP) labelled antibodies used as the second antibody were anti-NE-HRP for measuring total (free + complexed) NE level and anti-alpha 1-antitrypsin (AT)-HRP for complexed NE level. Mean value of total NE was 31.0 +/- 20.7 micrograms/ml in nasal secretions from adult patients with CS, and the percentage of complexed NE in total NE was 33.7 +/- 21.4%. This sandwich ELISA is a useful method for measuring both total and complexed NE levels in nasal secretions.

Patterns of protease activity and levels of protease inhibitors were analyzed in both nasal secretions and tissue extracts from patients with nasal allergy and non-atopic sinusitis to investigate the role of proteases in the inflammatory reaction. Protease activity was measured using specific methyl-coumaryl-7-amide substrates. The pattern of protease activity in the nasal secretions of chronic sinusitis patients was similar to that in neutrophil lysate and quite different from that in plasma. Both gluthatione activation testing and inhibition testing using synthetic inhibitors revealed that the majority of proteases in both secretions and tissues are lysosomal thiol proteases such as cathepsins B and L. Neutrophilic elastase is also a major protease in nasal secretions. In acute sinusitis, both protease activity and inhibitor levels were very high, suggesting an interaction between proteases and inhibitors. Cathepsin B and B-like thiol proteases appear to play a key role in prolonging chronic inflammation against the healing process, due to their resistance to plasma inhibitors and the shortage of thiol protease inhibitors. Protease activity in the secretions of nasal allergy patients was very weak, and the reaction between proteases and inhibitors appeared to be weak.

The purpose of this study was to clarify the clinical significance of rest-redistribution in myocardial scintigraphy (SPECT) in acute myocardial infarction (AMI). Thirty patients with AMI within one week after the onset of attack were studied. SPECT images were obtained 10 min and three hours after injection of 201Tl. Bull's eye images and unfolded map images were prepared. A 201Tl uptake was studied at the infarct and non-infarct sites. Exercise SPECT and radionuclide angiography (RNA) were performed in all patients one month after the onset of AMI, and the findings were compared with clinical and coronary angiographic (CAG) findings. 1. Redistribution of thallium at rest was observed at the infarct sites in nine of the 30 patients. 2. Redistribution at rest was observed at the non-infarct sites in eight patients. 3. Redistribution at rest was observed during exercise SPECT one month after the onset of AMI in patients with redistribution at rest in the acute phase. 4. In patients with redistribution at rest at the infarct site, left ventricular ejection fraction (EF) improved one month after the onset of AMI (delta EF greater than 5%), but it decreased slightly during exercise. 5. Wall motion at the infarct site was not much impaired in patients who showed redistribution at rest at the infarct site. 6. Angina pectoris and recurrence of myocardial infarction were observed more frequently in those with redistribution at rest on SPECT. 7. No characteristic findings were obtained on CAG in those with redistribution at rest.(ABSTRACT TRUNCATED AT 250 WORDS)

A preliminary study on the prevalence of antibodies to respiratory syncytial virus (RSV) in individuals of various age-groups was carried out. In healthy infants aged 6 to 12 months, the prevalence was 27%. It increased to 37 and 54% in children aged 1 to 2 and 2 to 4 years, respectively. The prevalence reached 78% in healthy individuals who were more than 20 years old, including pregnant women. Significant levels of specific antibodies were detected in 59% of children aged 6 to 12 months who were hospitalized with respiratory tract illnesses. It appears that acquisition of antibodies to RSV in our population occurs relatively later in life than in other Western countries.

An enzyme active against p-nitrophenyl-beta-d-cellobioside was purified from Ruminococcus albus to homogeneity. The enzyme was identified as a cellobiosidase.