Response-oriented individualized induction therapy with six drugs followed by four courses of intensive consolidation, 1 year maintenance and intensification therapy: the ALL90 study of the Japan Adult Leukemia Study Group

Adult patients with acute lymphoblastic leukemia (ALL) were treated according to the ALL90 study, the second prospective study for ALL of the Japan Adult Leukemia Study Group (JALSG). Its characteristics included response-oriented individualized induction therapy with six drugs (doxorubicin, mitoxantrone, vincristine, prednisolone, [corrected] cyclophosphamide and L-asparaginase), and a prospective comparison between allogeneic bone marrow transplantation (allo-BMT) and chemotherapy alone in patients below 45 years of age. The protocol consisted of one or two courses of induction, four courses of consolidation, and three courses of intensification including 12 month maintenance and six times of central nervous system (CNS) prophylaxis. Of 180 evaluable patients (median age, 43), 125 (69%) achieved complete remission (CR). Predicted overall survival (OAS), event-free survival and disease-free survival (DFS) were 15, 10 and 14%, respectively at the median follow-up period of 62 months. No specific toxicities were observed. Leukocytes < 30,000/microliter, normal karyotype, and blasts < 10% in bone marrow at day 15 of induction therapy were significantly favorable prognostic factors for the achievement of CR, DFS and OAS by univariate analysis. Multivariate analysis showed leukocytes < 30,000/microliter and blasts < 10% on day 15 was a significant factor for the achievement of CR, DFS and OAS. Ph-chromosome was found in 28% (36/130) of patients examined and was one of the worst prognostic factors. All Ph positive patients were predicted to die within 600 days. Allo-BMT was not significantly superior to chemotherapy with respect to DFS (P = 0.226). The overall results were inferior to those of the former ALL87 protocol. As reasons, the older median age of 43 years old (vs. 38 years old) and lower dose intensity, especially of l-asparaginase, etc. were suggested. However, patients with good prognostic factors (leukocyte < 30,000/microliter and age < 30 years old) showed better survival than others (P < 0.0001), and the result was similar to that of older children, the high risk group of childhood ALL, suggesting that ALL could be a disease of single entity, showing higher resistance to chemotherapy as patients become older.

A long term follow-up of a randomized trial comparing interferon-alpha with busulfan for chronic myelogenous leukemia. The Kouseisho Leukemia Study Group

To evaluate the long-term effectiveness of interferon-alpha (IFN-alpha) therapy in patients with chronic myelogenous leukemia (CML) in chronic phase, we examined the updated outcomes of 159 patients who had been enrolled between 1988 and 1991 into a randomized trial comparing IFN-alpha with busulfan. At a median follow-up of 73 months, the median survival was 71 months in the IFN-alpha group and 55 months in the busulfan group (P=0.0563), and the median time of remaining in chronic phase was 58 months in the IFN-alpha group and 39 months in the busulfan group (P=0.4676). Landmark analysis showed a significant advantage in survival (P=0.009) and duration of chronic phase (P=0.0001) in patients with any cytogenetic response among the IFN-alpha group. About half patients were discontinued IFN-alpha administration in spite of cytogenetic response in this study. It appears that continuation of IFN-alpha might possibly confer a survival advantage. Pretreatment factors associated with cytogenetic response included high hemoglobin level, low percentage of peripheral basophils and low leukocyte counts. Multivariate analysis identified lower percentage of bone marrow basophilia (P=0.007) for survival advantage. If a group with a very good prognosis is predicted by a new prognostic model, it might be an option to wait for bone marrow transplantation.

Polyethylene glycol-modified bilirubin oxidase improves hepatic energy charge and urinary prostaglandin levels in rats with obstructive jaundice

BACKGROUNDS/AIMS

No study has so far been conducted to clarify whether the presence of hyperbilirubinemia is detrimental to liver and renal functions. In the present study, the effects of polyethylene glycol-modified bilirubin oxidase (PEG-BOX) therapy on liver and renal function tests, hepatic energy charge and urinary prostaglandin levels were evaluated in a rat model of obstructive jaundice.

METHODS

Sprague-Dawley rats were used in the experimental model of obstructive jaundice. PEG-BOX or an equivalent amount of PEG alone was intravenously injected into the animals and sampling of blood and urine, and liver harvesting were done sequentially after bile duct ligation.

RESULTS

Conventional liver function tests showed no difference between PEG-BOX and control groups. However, bilirubin concentrations in the peripheral blood and liver tissue specimens markedly decreased, and the hepatic energy charge significantly increased in the PEG-BOX group as compared to controls. The blood concentration of bile acid was lower, but its urinary excretion was higher in the PEG-BOX group than in the control group. In vitro incubation of PEG-BOX with serum from rats with obstructive jaundice decreased the concentration of bilirubin but not that of bile acid. The urinary levels of prostaglandin E2 and the thromboxane B2/6-keto-prostaglandin Fla ratio were significantly lower in the PEG-BOX group than in the control group.

CONCLUSIONS

The systemic reduction of bilirubin concentration may contribute to normalization of the urinary levels of prostaglandins and thromboxane B2, to decrease in serum bile acid levels, and to improvement of the hepatic energy charge in obstructive jaundice. These findings suggest that preoperative improvement of jaundice may be beneficial to patients with obstructive jaundice.

Analysis of prognostic factors in newly diagnosed acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy. Japan Adult Leukemia Study Group

PURPOSE

We conducted a multicenter study of differentiation therapy with all-trans retinoic acid (ATRA) followed by intensive chemotherapy in patients with newly diagnosed acute promyelocytic leukemia (APL) and analyzed the prognostic factors for predicting complete remission (CR), event-free survival (EFS), and disease-free survival (DFS).

PATIENTS AND METHODS

All patients received ATRA until CR. If patients had an initial leukocyte count greater than 3.0 x 10(9)/L, they received daunorubicin (DNR) and behenoyl cytarabine (BHAC). During therapy, if patients showed blast and promyelocyte counts greater than 1.0 x 10(9)/L, they received additional DNR and BHAC. After achieving CR, patients received three courses of consolidation and six courses of maintenance/intensification chemotherapy.

RESULTS

Of 198 registered, 196 were assessable (age range, 15 to 86 years; median, 46) and 173 (88%) achieved CR. Multivariate analysis showed that no or minor purpura at diagnosis (P = .0046) and age less than 30 years (P = .0076) were favorable factors for achievement of CR. Predicted 4-year overall survival and EFS rates were 74% and 54%, respectively, and the 4-year predicted DFS rate for 173 CR patients was 62%. Multivariate analysis showed that age less than 30 years (P = .0003) and initial leukocyte count less than 10 x 10(9)/L (P = .0296) were prognostic factors for longer EFS, and initial leukocyte count less than 10.0 x 10(9)/L was a sole significant prognostic factor for longer DFS (P = .0001).

CONCLUSION

Our results show that age, hemorrhagic diathesis, and initial leukocyte count are prognostic factors for APL treated with ATRA followed by intensive chemotherapy.

Incisor crossbite and repaired unilateral cleft lip and palate: changes in jaw movement and temporalis muscle activity before and after edgewise treatment--case report

OBJECTIVE

To examine the changes in jaw movement and temporalis muscle activity of a patient with unilateral cleft lip and palate before and after edgewise treatment.

DESIGN

Clinical case study.

SETTING

University dental hospital, department of orthodontics.

PATIENT

A 12-year 3-month-old male with incisor crossbite, molar malocclusion, and repaired unilateral cleft lip and palate who had completed first-phase orthodontic treatment.

MAIN OUTCOME MEASURES

This patient was treated with an edgewise appliance. Jaw movement and temporalis muscle activity during the chewing of a hard gummy jelly were recorded at 2 kHz from the sixth to the twentieth stroke before edgewise treatment and after a retention period of 2 years.

RESULTS

Optimum intercuspation of teeth was achieved. The reversed crossing jaw-movement pattern before treatment changed to a normal grinding after treatment. The posterior temporalis muscle on the chewing side exhibited an earlier burst than the contralateral one during chewing at the post-treatment stage, as is observed in cases with good occlusion.

CONCLUSION

Improvement in the occlusion using an edgewise appliance is necessary for acquiring a good masticatory function in patients with incisor crossbite, molar malocclusion, and cleft lip and palate.

Changes in jaw movement and jaw closing muscle activity after orthodontic correction of incisor crossbite

The possible influences of the direction of occlusal loading delivered to the incisors in the sagittal direction during chewing on jaw movement and jaw closing muscle activity were investigated. Ten healthy children with crossbite of one or two incisors on the right side were selected. Each subject chewed a piece of chewing gum on the right side, and jaw displacements and electromyographic signals from the posterior temporalis and superficial masseter muscles on the ipsilateral side were sampled simultaneously. After orthodontic correction of the incisor crossbite relationship, identical records were taken. The inclinations of the gliding contacts for each posterior tooth in the lateral jaw excursion position were consistent before and after the treatment. The posttreatment records showed broader jaw movement patterns in the frontal view and faster jaw movement velocity in the lateral direction at a level close to the habitual maximum intercuspation position, when compared with the pretreatment records (P < 0.05). The duration of the muscle activity and the incidence of the silent periods of the masseter muscle during chewing significantly decreased after the treatment (P < 0.05). The current results give a neurophysiologic rationale for explaining the significance of orthodontic treatment in improving lowered masticatory efficiency in the way that the change in direction of the occlusal load achieved by tooth movement influences on the periodontal sensory input, which, in turn, modifies the trigeminal motor output and thus, eventually, jaw muscle activities.

[Newer approach of screening test for antinuclear antibodies: an enzyme-linked immunosorbent assay detecting antinuclear antibodies characteristic of connective tissue diseases]

An enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of antinuclear antibodies (ANAs) previously established as diagnostic and/or prognostic marker ANAs for various connective tissue diseases. The antigen used in ELISA is a mixture of purified recombinant or natural antigens including single-and double-stranded DNA, RNP, Sm, SS-A/Ro, SS-B/La, centromere, topoisomerase I and Jo-1 antigens. Thirty hundred and fifty nine patients sera from a variety of connective tissue diseases and 113 normal human sera (NHS) were examined. ELISA ANAs were positive in 3.5% of NHS and 80.2% of patients sera at cut off index 11.5, whereas indirect immunofluorescent antinuclear antibodies (FANAs) using HEp-2 cells were positive in 9.7% of NHS and 92.5% of patients sera at 1:160 serum dilution. More than 80% of sera from systemic lupus erythematosus, mixed connective tissue disease and primary Sjögrens disease were ELISA ANAs positive. Mean value of ELISA ANAs was highest in sera of patients with MCTD. ELISA ANAs were positive in 92.5% of sera with marker ANAs for connective tissue diseases. Mean value of ELISA ANAs was higher in sera with more than two marker ANAs than in sera with a single ANA or in sera without marker ANAs. In contrast incidence and mean value of ELISA ANAs were low in sera positive for anti topoisomerase I antibody or anti Jo-1 antibody. Sensitivity, specificity and agreement (accuracy) for connective tissue diseases with marker ANAs were as follows: ELISA ANAs (at index 11.5): 92.5%, 88.3% and 90.9%: FANAs (at 1:160 serum dilution): 99.0%, 70.4% and 88.1%, respectively. ELISA ANAs, thus, are specific for connective tissue diseases when compared to FANAs and previous ELISA for the detection of total ANAs. Moreover, ELISA ANAs are able to measure precise ANAs titers and are much less labor intensive when screening a large number of clinical specimens.

Analysis of expression of lymphocyte homing-related adhesion molecules in ALY mice deficient in lymph nodes and Peyer's patches

The aly, alymphoplasia, is an autosomal recessive mutation in mice of an unknown etiology, which induces total aplasia of lymph nodes and Peyer's patches. We hypothesized that the lack of lymphoid tissue may be due to abnormalities of lymphocyte traffic into these tissues. Therefore, we analyzed the expression of various adhesion molecules associated with lymphocyte homing. Among the adhesion molecules examined, all were normally expressed except the mucosal addressin MAdCAM-1. In aly/aly mice MAdCAM-1 was absent in the spleen at mRNA and protein levels, but was normally expressed in the intestinal venules. The FISH analysis and linkage analysis using microsatellite markers demonstrated that the MAdCAM-1 gene is located on chromosome 10, indicating that MAdCAM-1 is not encoded by the aly gene, which is located on chromosome 11. Our results indicate that the aberrant expression of MAdCAM-1 is not the direct cause of aly mutation but rather a secondary defect.

Human urinary macrophage colony-stimulating factor reduces the incidence and duration of febrile neutropenia and shortens the period required to finish three courses of intensive consolidation therapy in acute myeloid leukemia: a double-blind controlled study

PURPOSE

To determine whether macrophage colony-stimulating factor (M-CSF) reduces the incidence and duration of febrile neutropenia during three courses of intensive consolidation therapy and whether it shortens time to complete consolidation therapy.

PATIENTS AND METHODS

In 198 adult patients with acute myeloid leukemia (AML) in complete remission (CR), M-CSF (8 x 10(6) U/d) or placebo was administered from 1 day after the end of each consolidation chemotherapy for 14 days.

RESULTS

The duration and incidence of febrile neutropenia was significantly reduced by 34% (P = .00285) and 17% (P = .02065), respectively, in 88 assessable patients in the M-CSF group compared with those in 94 assessable patients in the placebo group. Patients in the M-CSF group had 565 days and 133 episodes of febrile neutropenia during 7,901 days at risk, while patients in the placebo group had 977 days and 185 episodes during 9,077 days at risk. The median period required to finish the three courses of consolidation therapy was 93 days in the M-CSF group, which was significantly shorter than 110 days in placebo group (P = .0050). In the M-CSF group, the recovery of neutrophils and platelets was significantly faster (P = .0348 and P = 0.0364, respectively), the administration of systemic antimicrobial agents tended to be less (P = .0839), and the frequency of platelet transfusion (P = .0259) and the total volume of transfused platelets (P = .0292) were significantly less. However, there was no significant difference in the disease-free survival.

CONCLUSION

M-CSF significantly reduced the incidence and duration of febrile neutropenia during the intensive consolidation therapy, and shortened the time to complete consolidation chemotherapy in AML.

Treatment with a new synthetic retinoid, Am80, of acute promyelocytic leukemia relapsed from complete remission induced by all-trans retinoic acid

Differentiation therapy with all-trans retinoic acid (ATRA) has marked a major advance and become the first choice drug in the treatment of acute promyelocytic leukemia (APL). However, patients who relapse from ATRA-induced complete remission (CR) have difficulty in obtaining a second CR with a second course of ATRA therapy alone. We tested the efficacy of a new synthetic retinoid, Am80, in APL that had relapsed from CR induced by ATRA in a prospective multicenter study. Am80 is approximately 10 times more potent than ATRA as an in vitro differentiation inducer, is more stable to light, heat, and oxidation than ATRA, has a low affinity for cellular retinoic acid binding protein, and does not bind to retinoic acid receptor-gamma. Patients received Am80, 6 mg/m2, orally alone daily until CR. Of 24 evaluable patients, 14 (58%) achieved CR. The interval from the last ATRA therapy was not different between CR and failure cases. The clinical response was well correlated with the in vitro response to Am80 in patients examined. Adverse events included 1 retinoic acid syndrome, 1 hyperleukocytosis, 9 xerosis, 8 cheilitis, 16 hypertriglyceridemia, and 15 hypercholesterolemia, but generally milder than those of ATRA, which all patients had received previously. Am80 is effective in APL relapsed from ATRA-induced CR and deserves further trials, especially in combination with chemotherapy.

On the key role of secondary lymphoid organs in antiviral immune responses studied in alymphoplastic (aly/aly) and spleenless (Hox11(-)/-) mutant mice

The role of the spleen and of other organized secondary lymphoid organs for the induction of protective antiviral immune responses was evaluated in orphan homeobox gene 11 knockout mice (Hox11(-/-)) lacking the spleen, and in homozygous alymphoplastic mutant mice (aly/aly) possessing a structurally altered spleen but lacking lymph nodes and Peyer's patches. Absence of the spleen had no major effects on the immune response, other than delaying the antibody response by 1-2 d. In aly/aly mice, the thymus-independent IgM response against vesicular stomatitis virus (VSV) was delayed and reduced, whereas the T-dependent switch to the protective IgG was absent. Therefore, aly/aly mice were highly susceptible to VSV infection. Since aly/aly spleen cells yielded neutralizing IgM and IgG after adoptive transfer into recipients with normally structured secondary lymphoid organs, these data suggest that the structural defect was mainly responsible for inefficient T-B cooperation. Although aly/aly mice generated detectable, but reduced, CTL responses after infection with vaccinia virus (VV) and lymphocytic choriomeningitis virus (LCMV), the elimination of these viruses was either delayed (VV) or virtually impossible (LCMV); irrespective of the dose or the route of infection, aly/aly mice developed life-long LCMV persistence. These results document the critical role of organized secondary lymphoid organs in the induction of naive T and B cells. These structures also provide the basis for cooperative interactions between antigen-presenting cells, T cells, and B cells, which are a prerequisite for recovery from primary virus infections via skin or via blood.

A C57BL/KsJ mouse model of Niemann-Pick disease (spm) belongs to the same complementation group as the major childhood type of Niemann-Pick disease type C

A cell line (SPM-3T3) derived from a C57BL/KsJ mouse model of Niemann-Pick disease type C (NP-C) shows biochemical abnormalities similar to those in fibroblasts derived from NP-C. Somatic cell hybridization analysis of the SPM-3T3 cells and five fibroblast strains derived from NP-C patients (four childhood cases and one adult case) was carried out. The criterion for complementation was the restoration of a normal intracellular fluorescent pattern in multinucleated cells stained with filipin to demonstrate cholesterol accumulation. These cells can be assigned to two complementation groups. The SPM-3T3 cells did not complement cell strains derived from childhood-type NP-C, while they complemented a cell strain derived from an adult patient. Our results suggest that SPM-3T3 represents a genetically authentic model of a major complementation group of NP-C, and that NP-C consists of genetically heterogeneous groups.

[A case report of typical scleroderma accompanied with serum abnormalities characteristic of SLE during the course]

A 40-year-old woman had complained of cyanosis induced by cold exposure from the age of 26. When she was 32 years old, Raynaud's phenomenon occurred. She developed diffuse cutaneous sclerosis affecting the upper limbs, face and trunk, digital pitting scar, flexion contractures of hands, dilatation of lower esophagus and pulmonary fibrosis, and she was diagnosed as scleroderma. Laboratory findings revealed positive anti-topoisomerase I antibody and hypergammaglobulinemia (IgG 2,782, IgA 632, IgM 146 mg/dl). However, serum complement levels were normal and anti-DNA antibodies measured by radioimmunoassay (RIA) were negative. Initial dose of oral prednisolone was 30 mg/day and afterwards 5 mg/day of prednisolone was maintained. At the age of 36, scleroderma and contraction of hands were progressed, and telangiectasias appeared on her chest at the age of 36. Laboratory tests revealed hypocomplementemia (C3 27, C4 9 mg/dl, CH50 16 U/ml) and high titers, more than 100 U/ml, of anti-DNA antibodies measured by RIA. Clinical evidence suggestive of SLE could not be found. Reexamination of previous sera by enzyme immunoassay, in which anti-DNA antibody could not be detected by RIA, clarified the presence of IgG anti-dsDNA antibodies. It was considered that there existed low avidity/affinity of anti-dsDNA antibodies at first, and afterwards high avidity/affinity of anti-dsDNA antibodies appeared. Increasing of oral prednisolone up to 30 mg/day normalized serum complements and decreased titers of anti-DNA antibodies. She had not developed any clinical evidence that suspected SLE throughout the course.

Serum beta-2-microglobulin in patients with multiple myeloma treated with alpha interferon

In ten patients with multiple myeloma (MM), serum beta-2-microglobulin (B2M) levels were monitored in order to clarify the influence of alpha interferon (IFN) administration. Despite decreases in M-protein and the absence of renal dysfunction, the levels of serum B2M were sustained above those prior to melphalan-prednisolone and IFN therapy in seven patients with MM for six months. Serum B2M did not increase in ten patients with MM treated only by melphalan-prednisolone. Furthermore, serum B2M levels in a patient who achieved a complete response were sustained above her prior level and returned to normal after cession of IFN therapy. Our study suggests that the serum B2M level is increased by treatment with IFN, and does not prove the condition of the disease.

Selective breeding for high serum IgA levels from noninbred ddY mice: isolation of a strain with an early onset of glomerular IgA deposition

An outbred mouse strain known as ddY has been reported to spontaneously develop, late in life, mesangioproliferative glomerulonephritis with a severe glomerular immunoglobulin A (IgA) deposition that mimics human IgA nephropathy. However, the incidence of the disease in this strain is not very high, probably due to its heterogeneous genetic background. Therefore, we attempted to isolate a strain with a high incidence and an early onset of the disease through selection for high serum IgA from the outbred ddY mice. The selection procedure was successful in increasing the serum IgA level of the selected line and proved effective both in increasing the incidence and in accelerating the onset of the disease. We propose to designate this line of mice 'HIGA', denoting a line with high serum IgA levels. More than half of the mice from the HIGA strain showed a moderate to severe glomerular IgA deposition as early as 25 weeks of age. The severe deposition observed was comparable to that occasionally seen in the original nonselected ddY strain after 40 weeks of age. Thus, we have succeeded in generating a mouse model of IgA nephropathy with a high incidence and an early onset of glomerular IgA deposition. Using light microscopy, progressive and marked mesangial matrix accumulation was shown to develop in HIGA mice. However, they showed only mild proteinuria (100-300 mg/dl) and did not show hematuria.

Enhanced production of glomerular extracellular matrix in a new mouse strain of high serum IgA ddY mice

To investigate the relationship between high serum levels of IgA and glomerular lesions, selective mating was performed in high serum IgA ddY mice, a murine model of spontaneously developing mesangioproliferative glomerulonephritis mimicking human IgA nephropathy. The selection and mating of high IgA ddY mice were accomplished when the mice were three to four months old. In the 12th generation of high IgA ddY (HIGA) mice, significantly higher levels of serum IgA from 10 age weeks to 60 weeks (P < 0.0002 to 0.0001) were observed in comparison with BALB/c mice. Relatively high proteinuria was observed at 40 weeks of age, although hematuria was consistently negative. Microscopic observations of renal tissue disclosed a marked glomerular mesangial matrix increase and a reduction of cell proliferation with age by both semiquantitative and morphometric analyses with moderate tubulointerstitial damage. These mesangial matrices were stained markedly by antisera for collagen type IV and by fibronectin, but not by collagen type I. Localization of TGF-beta protein was also detected in the mesangium of the HIGA mice. The positive mesangial IgA deposition was maintained consistently by this mating procedure and became more marked with age. Size analysis of IgA from ten pooled HIGA mice aged 50 to 60 weeks revealed dominant polymeric IgA in sera and dimeric IgA in glomerular eluates. Clonal analysis of serum IgA disclosed heterogeneous spectrotypes in a wide pH range (4.5 to 6.5), in contrast to very limited spectrotypes in the acidic pH range (4.5 to 5.2) of IgA in the glomerular eluates from these mice. The analyses of retroviral gp70 antigen involvement in the HIGA mice disclosed a significant increase of serum levels of gp70 anti-gp70 immune complexes with age, with no relationship to the severity of glomerular gp70 deposition. Northern blot analysis of renal tissue revealed markedly high mRNA expression of collagen type I, IV, fibronectin and TGF-beta even in 10-week-old HIGA mice in comparison with BALB/c mice. The expression became more significant in 60-week-old animals. The genetic background required to induce the expansion of IgA-producing B-cell clones is suggested to be closely related to the increased gene expression of TGF-beta, which induces enhanced glomerular extracellular matrix (especially fibronectin) accumulation in HIGA mice, being possibly mediated by the mesangial deposition of dimeric and highly acidic IgA. This newly established strain may provide a model for investigating the relationship between progressive glomerular sclerotic lesions and the induction of pathogenic IgA in human IgA nephropathy.

Activation of circulating platelets by hyperthermal stress

To determine the involvement of activated platelets in the frequent thrombosis after hot hot-spring bathing, we examined effects of a hyperthermal stress on platelets in vivo. Plasma levels of beta-thromboglobulin (beta-TG) began to rise at 5 minutes and elevated significantly 10 minutes after the start of traditional 47 degrees C hot-spring bathing. In contrast, there was no significant factor 4 change in plasma beta-TG level through a control 10-minute bath in the same water at 42 degrees C. A beta-TG to platelet factor 4 ratio, a value suggested to be useful for evaluating clinical studies for in vitro versus in vivo granule release, was sufficiently high in each sampling, indicating that the experiment was performed without being influenced by artificial platelet activation. These data show that only a few minutes' hyperthermal stress can induce granule release from platelets in vivo.

Autoimmune disease of exocrine organs in immunodeficient alymphoplasia mice: a spontaneous model for Sjögren's syndrome

Mice homozygous for an autosomal recessive mutation aly (alymphoplasia) lack both lymph nodes and Peyer's patches, and show defects in both humoral and cellular immunity. Histopathological analysis revealed chronic inflammatory changes in exocrine organs such as the salivary gland, lacrimal gland, and pancreas of the homozygotes (aly/aly), but not the heterozygotes (aly/+). In these exocrine organs, mononuclear cells consisting mainly of CD4+ T cells infiltrate periductal areas, and, in some cases, the cell infiltration extended to lobules. The inflammatory changes in exocrine organs were transferred by a T cell-enriched fraction of spleen cells from homozygous animals. These results suggest that autoimmune mechanisms mediated by self-reactive T cells may be involved in the inflammatory lesions of various exocrine organs in the homozygous mice, although these mice show immunodeficiency. Inflammatory changes were also observed in the lung of the homozygotes. Since Sjögren's syndrome is characterized by diffuse lymphocyte infiltration in the periductal areas of the lacrimal and salivary glands and is occasionally associated with pulmonary disease, aly/aly mice may serve as a unique spontaneous model of Sjögren's syndrome.

[Decreased incidence of peripheral nuclear staining pattern by indirect immunofluorescent antibody technique using HEp-2 cells]

The immunofluorescence technique using HEp-2 cells is widely used for the detection of antinuclear antibodies in sera of patients with connective tissue diseases. Among different patterns of nuclear staining the incidence of peripheral pattern which is mainly produced by anti double-stranded DNA antibodies has been markedly decreased after using HEp-2 cells as nuclear substrates. Thirty-five sera in interphase cells and 44 sera in metaphase cells showed peripheral pattern at 1:1 serum dilution from 70 patients with various connective tissue diseases including 46 systemic lupus erythematosus. Metaphase cells nuclei were more sensitive to peripheral pattern than those in interphase cells. Assuming that the incidence of peripheral pattern at 1:1 dilution was 100%, the incidence of peripheral pattern at 1:20 serum dilution dropped into 57.1% in interphase cells and 38.6% in metaphase cells, respectively. The incidence of peripheral pattern at 1:40 dilution dropped into 65.7% in interphase cells and 56.8% in metaphase cells, respectively. Mean value and incidence of anti double-stranded DNA antibodies detected by RIA were significantly higher in sera with peripheral pattern than in sera without peripheral pattern. However, there were some sera which showed peripheral pattern without anti double-stranded DNA antibodies, or there are a few sera which had anti double-stranded DNA antibodies without peripheral pattern. The drop of the incidence of peripheral pattern might be due to interference effect of multiple different antinuclear antibodies. It is necessary to detect anti double-stranded DNA antibodies directly by radioimmunoassay or enzyme-linked immunosorbant assay if occurrence of anti double-stranded DNA antibodies is clinically suspected without peripheral immunofluorescent pattern.

Defects of somatic hypermutation and class switching in alymphoplasia (aly) mutant mice

The alymphoplasia (aly) mutation of mice causes the systemic absence of lymph nodes, Peyer's patches and well-defined lymphoid follicles in the spleen. We found that antibody responses are elicited, albeit weakly, to either T cell-dependent or T cell-independent antigen by aly/aly mutants. However, isotype switching was defective. The T cell-dependent immune response was not elicited in splenectomized aly/aly mice. Neither hypermutation nor germinal center formation was observed in aly/aly mice. These results suggest that T-B collaboration requires either lymph nodes or spleen, and that hypermutation and affinity maturation depend on germinal center formation.

Inactivation of multiple tumor-suppressor genes involved in negative regulation of the cell cycle, MTS1/p16INK4A/CDKN2, MTS2/p15INK4B, p53, and Rb genes in primary lymphoid malignancies

It is now evident that the cell cycle machinery has a variety of elements negatively regulating cell cycle progression. However, among these negative regulators in cell cycle control, only 4 have been shown to be consistently involved in the development of human cancers as tumor suppressors: Rb (Retinoblastoma susceptibility protein), p53, and two recently identified cyclin-dependent kinase inhibitors, p16INK4A/MTS1 and p15INK4B/MTS2. Because there are functional interrelations among these negative regulators in the cell cycle machinery, it is particularly interesting to investigate the multiplicity of inactivations of these tumor suppressors in human cancers, including leukemias/lymphomas. To address this point, we examined inactivations of these four genes in primary lymphoid malignancies by Southern blot and polymerase chain reaction-single-strand conformation polymorphism analyses. We also analyzed Rb protein expression by Western blot analysis. The p16INK4A and p15INK4B genes were homozygously deleted in 45 and 42 of 230 lymphoid tumor specimens, respectively. Inactivations of the Rb and p53 genes were 27 of 91 and 9 of 173 specimens, respectively. Forty-one (45.1%) of 91 samples examined for inactivations of all four tumor suppressors had one or more abnormalities of these four tumor-suppressor genes, indicating that dysregulation of cell cycle control is important for tumor development. Statistical analysis of interrelations among impairments of these four genes indicated that inactivations of the individual tumor-suppressor genes might occur almost independently. In some patients, disruptions of multiple tumor-suppressor genes occurred; 4 cases with p16INK4A, p15INK4B, and Rb inactivations; 2 cases with p16INK4A, p15INK4B, and p53 inactivations; and 1 case with Rb and p53 inactivations. It is suggested that disruptions of multiple tumor suppressors in a tumor cell confer an additional growth advantage on the tumor.