Development of noninvasive tonometer using resonance phenomenon

A tonometer is used to measure ocular pressure either by shooting a short blast of compressed air onto the cornea or by applying pressure directly to the cornea. At present, the tonometer is the primary instrument available for measuring ocular pressure. However, measuring ocular pressure by such means can either frighten or injure the patient. We propose an improved method of measuring ocular pressure in which the tonometer is applied over the patient's closed eyelid for several seconds. The sensor part of the newly developed tonometer contains a bimorph type transducer and weighs only 28.7 (g). When the sensor is placed on the eyelid and the transducer is vibrated by altering the applied voltage, the current flowing through the transducer changes in relation to the ocular pressure. Ocular pressure can thus be determined based on the current flowing through the system. During measurement, patients are generally unaware of the vibrations of the sensor and report no pain.

Functional human IgE specific for Dermatophagoides farinae antigen is produced in SCID mice reconstituted with peripheral mononuclear cells derived from healthy persons and patients with asthma

BACKGROUND

Whether normal peripheral blood mononuclear cells (PBMCs) transferred to severe combined immunodeficient (SCID) mice produce specific IgE remains unclear.

METHODS

Mice received injections of Dermatophagoides farinae antigen (Df)-stimulated PBMCs from healthy persons (IgE RAST score of 0).

RESULTS

High titers of Df-specific IgE were detected. The Df-specific IgE activity produced was comparable to or higher than that produced by cells from patients with asthma although the time to maximal production was longer. IgE derived from PMBCs of healthy persons or patients with asthma induced histamine release from cultured human basophils that had been stimulated with Df antigen or an anti-IgE antibody. Treatment of Df-stimulated PBMCs with a high dose, but not a low dose, of interleukin-4 stimulated production of Df-specific IgE by PMBCs from healthy persons or patients with asthma. In contrast, intravenous injection of IFN-gamma into reconstituted SCID mice decreased Df-specific IgE production by PBMCs from patients with asthma. In PMBCs from healthy persons, IgE class-switching may occur later and block the effects of treatment with IFN-gamma.

CONCLUSIONS

PBMCs from healthy persons and persons with asthma have clones reactive to allergen and produce functional IgE specific for relevant antigens in mite-sensitive bronchial asthma.

Fatal buckwheat dependent exercised-induced anaphylaxis

Cases of food-dependent exercise-induced anaphylaxis (FEA) caused by buckwheat have been rare. Clinical, laboratory, and autopsy findings are present on an 8-year old girl with FEA caused by Japanese buckwheat. The patient consumed buckwheat noodles called "zaru soba" and immediately thereafter swam vigorously. Approximately 30 minutes later, she complained of abdominal pain, vomiting, coughing, and chest discomfort. Another ten minutes later her consciousness level deteriorated and she experienced cardiorespiratory arrest. The heart beat was restored and she was admitted to the hospital. She never regained consciousness and expired after another arrest 13 days later. Her IgE level was high (2,840 IU/ml) and the IgE-radioallergosorbent test (RAST) score was 2 for soybeans, 3 for buckwheat, 2 for rice, and 3 for wheat. An exaggerated hematemesis that occurred immediately after hospital admission indicated an inflammatory condition of the digestive tract that was caused by buckwheat. Marked ulceration accompanied with hemorrhage and necrosis was noted at the ileum. Extensive hemorrhage involving the endotracheal pulmonary field and lymphocyte infiltration of the alveolar space likely appeared after the inflammation. The analysis of buckwheat-specific IgE antibody by immunoblotting showed 7 bands that reacted with the IgE of the patient's serum, 4 bands: 16, 20, 24, and 58 kDa, were specific to the patient as compared to subjects not allergic to buckwheat. A first case of fatal FEA by buckwheat is reported with reference to specific IgE.

Effect of roxithromycin on T lymphocyte proliferation and cytokine production elicited by mite antigen

Clinical evidence suggests that roxithromycin (RXM) may be an effective additional therapy for bronchial asthma. However, how it interferes with allergic responses is unclear. To investigate the mechanisms of action of RXM, lymphocyte transformation and interferon (IFN)-gamma, interleukin (IL)-4 and IL-5 synthesis associated with Dermatophagoides farinae (Df), mite antigen in patients with bronchial asthma were evaluated in vitro in the presence of RXM. T cell proliferation in Df antigen-stimulated patients' lymphocytes was suppressed by 50-100 microg/ml of RXM. Production of IL-4 and IL-5 was similarly decreased by 1-10 microg/ml RXM, whereas, IFN-gamma production, which was reduced by Df-stimulation alone, was increased by 50 microg/ml RXM. Our results suggest that skewed cytokine profiles of patients with mite antigen-induced bronchial asthma may be corrected with RXM, which may mimic those of patients in remission, who are tolerant of Df antigen.

Enhancement of mucosal immune response against HIV-1 Gag by DNA immunization

In order to examine the feasibility of Gag-expression DNA as a potential candidate for HIV vaccine using a mouse model, we injected DNA into mice either intramuscularly or by using a gene gun. Both methods induced a low level of antibody production. However, after booster immunization with p24 protein emulsified with complete Freund's adjuvant via a footpad, we found that only the preceding intramuscular DNA immunization induced an anti-Gag Th1-type (IgG(2a)) antibody response, in addition to the enhancement of a Th2-type (IgG(1)) antibody response. Importantly, when mice were boosted intranasally with p24 and cholera toxin, intramuscular DNA injection was found to enhance both systemic and mucosal Gag-specific immune responses. These results indicate that intramuscular DNA immunization confers the inducibility of memory cells, which circulate around various mucosal tissues. Therefore, intramuscular DNA priming, followed by a mucosal booster immunization, could be considered as a regimen applicable to HIV vaccine.

Studies on the interactions between drugs and estrogen: analytical method for prediction system of gynecomastia induced by drugs on the inhibitory metabolism of estradiol using Escherichia coli coexpressing human CYP3A4 with human NADPH-cytochrome P450 reductase

To establish a prediction system for drug-induced gynecomastia in clinical fields, a model reaction system was developed to explain numerically this side effect. The principle is based on the assumption that 50% inhibition concentration (IC(50)) of drugs on the in vitro metabolism of estradiol (E2) to its major product 2-hydroxyestradiol (2-OH-E2) can be regarded as the index for achieving this purpose. By using human cytochrome P450s coexpressed with human NADPH-cytochrome P450 reductase in Escherichia coli as the enzyme, the reaction was examined. Among the nine enzymes (CYP1A1, 1A2, 2A6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4) tested, CYP3A4 having a V(max)/K(m) (ml/min/nmol P450) value of 0.32 for production of 2-OH-E2 was shown to be the most suitable enzyme as the reagent. The inhibitory effects of ketoconazole, cyclosporin A, and cimetidine toward the 2-hydroxylation of E2 catalyzed by CYP3A4 were obtained, and their IC(50) values were 7 nM, 64 nM, and 290 microM, respectively. The present results suggest that IC(50) values thus obtained can be substituted as the prediction index for gynecomastia induced by drugs, considering the patients' individual information.

Detection and measurement of urinary 2-hydroxyestradiol 17-sulfate, a potential placental antioxidant during pregnancy

BACKGROUND

Preeclampsia is associated with a quantitative imbalance between lipid peroxide and an antioxidant coproduced in the placenta. To investigate our hypothesis that 2-hydroxyestradiol 17-sulfate (2-OH-ES) is the placental antioxidant during pregnancy, we developed an assay for 2-OH-ES in urine and studied samples from women with and without preeclampsia.

METHODS

The detection and measurement of 2-OH-ES in the urine of pregnant women were performed by RIA using highly specific antiserum to 2-OH-ES. To confirm the reliability of the RIA method, the same samples were analyzed by HPLC using an electrochemical detector.

RESULTS

Urinary 2-OH-ES values obtained by RIA showed a close relationship to those obtained by HPLC (y = 1.1x - 0.01; r = 0.96). The urinary 2-OH-ES concentrations during the first, second, and third trimesters were 2. 0 +/- 0.6 (mean +/- SE, n = 13), 5.3 +/- 1.3 (n = 21), and 15.3 +/- 2.0 microg/mg creatinine (n = 54), respectively, and <0.15 microg/mg creatinine (n = 10) at 2-24 h after delivery. The concentrations in preeclamptic women during the third trimester were significantly lower, 3.9 +/- 1.9 microg/mg creatinine (mean +/- SE, n = 12).

CONCLUSIONS

RIA can be used to measure urinary 2-OH-ES during pregnancy. The increase in urinary 2-OH-ES during gestation, its decrease after delivery, and the lower values in preeclampsia are consistent with a role of 2-OH-ES as a placental antioxidant.

Wild-derived inbred mice have a novel basis of susceptibility to polyomavirus-induced tumors

Polyomavirus induces a broad array of tumors when introduced into newborn mice of certain standard inbred strains, notably those bearing the H-2(k) haplotype. Susceptibility in these mice is conferred by an endogenous mouse mammary tumor virus superantigen (Mtv-7 sag) that acts to delete T cells required for polyomavirus-induced tumor immunosurveillance. In the present study we show that mice of two wild-derived inbred strains, PERA/Ei (PE) and CZECH II/Ei (CZ), are highly susceptible to polyomavirus but carry no detectable Mtv sag-related sequences and show no evidence of Vbeta deletion. C57BR/cdJ (BR) mice, which are H-2(k) but lack the endogenous Mtv-7, are highly resistant based on an effective anti-polyomavirus tumor immune response. When crossed with BR, both PE and CZ mice transmit their susceptibility in a dominant fashion, indicating a mechanism(s) that overrides the immune response of BR. Susceptibility in PE and CZ mice is not based on interference with antigen processing or presentation since cytotoxic T cells from BR can efficiently kill F(1)-derived tumor cells in vitro. The expected precursors of polyomavirus-specific cytotoxic T cells are present in both the wild inbred animals and their F(1) progeny. These findings indicate a novel basis of susceptibility that operates independently of endogenous superantigen and prevents the development of tumor immunity.

Functional interleukin-5 activity in peripheral blood mononuclear cells from adolescents with mite antigen asthma in remission

BACKGROUND

Asthma improves in most children during adolescence such that a small minority of patients exhibit clinically significant symptoms by the age of 20 years.

OBJECTIVE AND METHODS

To investigate late allergic reactions, including eosinophil inflammation, associated with outgrowing mite antigen-induced bronchial asthma during adolescence, the relationship between clinical status and functional activity of interleukin (IL)-5 produced by Dermatophagoides farinae (Df)-stimulated peripheral mononuclear cells (PBMCs) in culture was assessed in mouse IL-3-dependent cells transfected with the human IL-5 receptor gene.

RESULTS

Activity of IL-5 spontaneously produced by PBMCs from either patients with mite-sensitive bronchial asthma or nonatopic control subjects was low. The activity of IL-5 produced by PBMCs stimulated with concanavalin A was significantly higher. Upon challenge with specific allergens, such as Df antigen, but not with irrelevant antigens, including ovalbumin, the in vitro activity was increased in patients with active disease and decreased in patients in remission.

CONCLUSION

Results suggest that the antigen-specific up-regulation of functional IL-5 activity in late allergic reactions is reduced in patients in remission and likely to result in an improvement in clinical status. The Df antigen may suppress Df-induced responses in patients with asthma in remission.

Serum 2-hydroxyestradiol 17-sulphate in pregnancy

2-Hydroxyestradiol 17-sulphate (2-OH E2-17-S) is a catecholized form of sulphated estrogen. In vitro studies showed that its antioxidative effect is almost equal to that of free catecholestrogens, such as 2-OH E2 or 4-OH E2 and alpha-tocoferol, but the existance of 2-OH E2-17-S in human serum has not yet been made clear. 2-OH E2-17-S strongly antagonizes lipid peroxidation, and so it may play an important role in pregnancy, for example as an anti-oxidant in pregnancy-induced hypertension (PIH). The serum level of 2-OH E2-17-S was measured during mid to late pregnancy by a direct radioimmunoassay (RIA) without hydrolysis. The serum levels at 28-31 weeks, 32-35 weeks and 36-40 weeks of gestation were 4.68+/-0.93 (mean+/-SE), 8.38+/-1.21 and 18.31+/-3.41 nmol/l, respectively. The serum level in PIH cases at 36-40 weeks (4.64+/-1.29 nmol/l) was significantly lower than that in normal pregnancy. The 2-OH E2-17-S level in umbilical arteries was significantly higher than that in maternal peripheral vein. These results suggest that the feto-placental unit plays an important role in catecholizing E2-17-S to 2-OH E2-17-S, which may act as an antioxidant in pregnancy.

IL-12 affects Dermatophagoides farinae-induced IL-4 production by T cells from pediatric patients with mite-sensitive asthma

BACKGROUND

IL-12 is a critical cytokine in the regulation of immune responses produced by phagocytic cells exposed to microorganism infection.

OBJECTIVE

We sought to study the effect of low doses and high doses of IL-12 on TH1 versus TH2 cytokine expression to elucidate the etiology of mite antigen-sensitive bronchial asthma in infants.

METHODS

We studied the effect of IL-12 on Dermatophagoides farinae (Df) antigen-induced IL-4 production and subsequent production of IgE by PBMCs from pediatric patients with asthma.

RESULTS

Simultaneous addition of 1 to 10 ng/mL IL-12 to cultures enhanced Df-induced IL-4 production, although low doses (0.05 to 0.1 ng/mL) of IL-12 downregulated IL-4 production. Endogenous IL-12 is required for such production. These phenomena were not observed in Df-stimulated control PBMCs. In contrast, on stimulation with the same dose of Df, IFN-gamma production by patient PBMCs was enhanced in a dose-dependent fashion by addition of IL-12. Quantification analysis of RT-PCR-amplified DNA fragments by laser-induced fluorescence showed that a high dose of IL-12 augments mRNA expression for IL-4 protein synthesis, whereas a low dose of IL-12 inhibits IL-4 mRNA expression, and that the signal of mRNA for IFN-gamma protein synthesis was increased on Df stimulation in a dose-dependent fashion. Df-induced in vitro production of IgE and Df-specific IgE in serum from severe combined immunodeficient mice reconstituted with PBMCs were increased by treatment with high doses of IL-12, whereas low doses of IL-12 inhibited that production. The combined results indicate that at a low dose of IL-12, IL-4 and IFN-gamma production was regulated reciprocally; however, at high doses of IL-12, cells produced IL-4 and IFN-gamma simultaneously, and neither cytokine was regulated.

CONCLUSION

Low-dose and high-dose IL-12 induce TH1 responses, and high-dose IL-12 induces both TH1 responses and TH2 or TH0 responses. Consequently, the IL-4 production may overcome TH1-type cell activation of IgE production in patients with mite-sensitive bronchial asthma.

Synthesis of 6- and 7-hydroxyestradiol 17-sulfates: the potential metabolites of estradiol 17-sulfate by female rat liver microsomes

The potential ring-B hydroxylated metabolites of estradiol 17-sulfate (1) by female rat liver microsomes were chemically prepared as authentic compounds. They are 6alpha- and 6beta-hydroxyestradiol 17-sulfates (7 and 9), and 7alpha- and 7beta-hydroxyestradiol 17-sulfates (12 and 16), whose synthetic procedures are described.

Identification of estrogen-modified nucleosides from calf thymus DNA reacted with 6-hydroxyestrogen 6-sulfates

Two estrogen sulfates, pyridinium 3-methoxyestra-1,3, 5(10)-trien-6alpha-yl sulfate (3MeE-6alpha-S) and its 6beta-isomer (3MeE-6beta-S), synthesized as model compounds to demonstrate the carcinogenesis of estrogen, were found to react with calf thymus DNA to produce steroid-modified DNA adducts. Digestion of the DNA by nuclease P1 and phosphodiesterase I followed by alkaline phosphatase gave a deoxyribonucleoside fraction, of which N2-[3-methoxyestra-1,3, 5(10)-trien-6alpha-yl]deoxyguanosine, N2-[3-methoxyestra-1,3, 5(10)-trien-6beta-yl]deoxyguanosine, N6-[3-methoxyestra-1,3, 5(10)-trien-6beta-yl]deoxyadenosine, and N6-[3-methoxyestra-1,3, 5(10)-trien-6alpha-yl]deoxyadenosine (identified as a base adduct) were identified using HPLC by comparing them with authentic specimens prepared by reacting dG and dA with both sulfates. No steroid-dC adduct was detected in the digestion products of the DNA adduct, although dC reacted with the sulfates to form N4-[3-methoxyestra-1,3,5(10)-trien-6beta-yl]deoxycytidine. These results mean that estrogen 6-sulfate has an ability to modify DNA via the amino group of a guanine or adenine residue in DNA. The present studies imply that a sequential metabolism (hydroxylation and sulfation) at the C6-position of the estrogen molecule causes damage to DNA.

A comparative investigation of the restorative effects of roxithromycin on neutrophil activities

The effects of roxithromycin, a macrolide antibiotic, on neutrophil activities were investigated in six seriously handicapped patients with severe mental retardation. Neutrophil activities were evaluated by flow cytometry using a heparinized blood analysis method. All six patients showed decreased levels of neutrophil phagocytosis, intracellular killing, and CD11b expression. Treatment with roxithromycin in vitro selectively restored the decreased phagocytic and bactericidal activities of neutrophils in these patients. There was no significant restorative effect with cefaclor, ofloxacin, or aztreonam. These results suggest the need to consider therapeutic effects of antibiotics on neutrophil functions in patients at increased risk for bacterial infections due to decreased neutrophil activities.

Correlation between antigen-specific IL-2 response test and provocation test for egg allergy in atopic dermatitis

BACKGROUND

The antigen-specific interleukin-2 response (AIR) test using lymphocytes is effective in searching for the antigen which causes allergic diseases and understanding their disease activity.

OBJECTIVE AND METHODS

The correlation between the raw egg oral provocation test and egg white antigen-specific interleukin-2 (IL-2) response test was investigated in 123 children with infantile atopic dermatitis and 13 children with bronchial asthma.

RESULTS

Among the 83 who showed positive reactions to provocation, 75 also reacted positively to the AIR test (sensitivity, 90.4%), while among the 53 children who showed negative responses to antigen provocation, 45 produced negative responses to the AIR test (specificity, 84.9%). The specificity of egg white IgE RAST score and skin-prick test are 88.7 and 81.3% which are comparable to that of the AIR test. However, their sensitivity was low (38.6 and 66.7%). In the patterns of symptom developed in the provocation AIR displayed late and delayed type allergic responses in addition to the immediate type which RAST reflected. The RAST-negative group composed of 98 patients included 51 (52.0%) who exhibited positive reactions to the provocation test. Among these 44 responded positively to the AIR test (86.3%).

CONCLUSION

The AIR test is effective for screening egg white antigen as part of the tests for antigens responsible for allergic diseases and as a test to ascertain the relevant antigens, and that the conditions that could not be diagnosed by RAST can be detected by the AIR test.

Differential recognition of MBP epitopes in BALB/c mice determines the site of inflammatory disease induction

Although myelin basic protein (MBP)-recognizing T cells are not readily obtained after immunization of BALB/c mice with MBP (reflecting the BALB/c resistance to actively induced experimental autoimmune encephalomyelitis (EAE)), they can be expanded and cloned after several rounds of in vitro culture. The majority of BALB/c-derived clones recognize an epitope defined by MBP peptide 59-76. When transferred to naive BALB/c recipients, these clones cause classical EAE, with characteristic inflammation and demyelination of the central nervous system (CNS). We previously showed that two related clones recognizing a minor epitope, defined by MBP peptide 151-168, cause inflammation and demyelination preferentially of the peripheral nervous system (PNS). Because MBP has alternatively spliced isoforms, residues 151-168 are not present contiguously in all MBP isoforms. In order to determine whether induction of PNS disease is idiosyncratic to these sister clones, or related to their properties of epitope recognition, an independent T-cell line with similar recognition properties was studied. Clone 116F, derived from a BALB/c shiverer mouse, expresses a different T-cell receptor (TCR), with distinct TCR contact residues, but like the previously described T cells, this clone requires residues from both exons 6 and 7 for optimal stimulation. When adoptively transferred to BALB/c recipients, this clone preferentially induces disease of the PNS. A control BALB/c shiverer-derived MBP 59-76-recognizing clone, in contrast, induces CNS disease. These data strongly suggest that the site of disease initiation may correlate with epitope recognition, particularly when alternative isoforms are involved.

Reduced IL-1 production in adolescents with mite antigen asthma in remission

To determine the immunological mechanisms associated with outgrowing mite antigen-induced bronchial asthma during adolescence, we studied the relationship between clinical status and Dermatophagoides farinae (Df) antigen-induced peripheral cell activation by measuring IL-1alpha and IL-1beta production in patients with bronchial asthma. After antigen-driven restimulation in vitro, there was increased IL-1alpha, IL-1beta production by peripheral blood mononuclear cells (PBMC) from patients with active bronchial asthma, while cellular IL-1alpha, IL-1beta production was reduced in patients with asthma in remission. IL-1alpha and IL-1beta production by PBMC (possibly reflecting airway inflammation) after exposure to Df antigen might be down-regulated in patients outgrowing mite antigen-induced asthma, because lipopolysaccharide-induced IL-1alpha, IL-1beta production (seen in both normal individuals and patients with active asthma) was also reduced when patients were in remission.

Mutagenic specificity of model estrogen-DNA adducts in mammalian cells

Site-specifically modified oligodeoxynucleotides were used to explore the mutagenic properties of the model estrogen-DNA adducts N2-[3-methoxyestra-1,3,5(10)-trien-6(alpha, beta)-yl]-2'-deoxyguanosine (dG-N2-3MeE) and N6-[3-methoxyestra-1,3, 5(10)-trien-6(alpha,beta)-yl]-2'-deoxyadenosine (dA-N6-3MeE) in simian kidney (COS-7) cells. Oligodeoxynucleotides (5'TCCTCCTCXCCTCTC; X = dG, dA, dG-N2-3MeE, or dA-N6-3MeE) containing an unmodified or model estrogen lesion were inserted into single-stranded (ss) phagemid vectors. These ss vectors were transfected into COS-7 cells. The progeny plasmid obtained were used to transform Escherichia coli DH10B. The transformants were analyzed by oligodeoxynucleotide hybridization and sequencing to determine the mutation frequency and spectrum. Preferential incorporation of dCMP, the correct base, was observed opposite the dG-N2-3MeE lesion. Targeted mutations showing G --> T transversions were detected, along with a small number of G --> C transversions. When a dA-N6-3MeE-modified oligodeoxynucleotide was used, preferential incorporation of dTMP, the correct base, was also observed. Targeted mutations representing A --> T transversions were detected, accompanied by a small amount of A --> G transitions. The frequency of mutation observed opposite dA-N6-3MeE (17.5%) was 2.3 times higher than that observed opposite dG-N2-3MeE (7.5%). These results indicate that estrogen DNA adducts have mutagenic potential in mammalian cells.

T-cell responses to myelin basic protein in normal and MBP-deficient mice

BALB/c mice are resistant to the development of experimental autoimmune encephalomyelitis (EAE) after immunization with myelin basic protein (MBP). Previous studies of BALB/c mice suggest that MBP-specific T-cells can eventually be cloned from these mice, although they are either initially present in very low frequencies or are functionally anergic. To determine what role endogenous MBP expression plays in shaping the BALB/c T-cell repertoire, MBP-deficient BALB/c mice were constructed by breeding the shiverer (shi/shi) mutation onto the BALB/c background. These mice lack all conventional isoforms of MBP due to a deletion of MBP exons 3-7. Studies of the MBP-directed response of these mice suggest that endogenous MBP expression is directly responsible for EAE resistance in BALB/c mice, by quantitatively affecting expression of the T-cell repertoire. In contrast to wild-type BALB/c T-cells, uncloned T-cells from BALB/c shi/shi mice immunized with MBP proliferate in vitro to MBP and MBP peptides 59-76 and 89-101 and are able to induce severe EAE upon transfer to BALB/c recipients expressing MBP.

Effect of oxatomide on T-cell activation and the production of interferon-gamma in mite sensitive asthma

Interleukin-2 responsiveness of lymphocytes induced by Dermatophagoides farinae antigen was suppressed upon exposure to 20 to 2000 ng/ml of oxatomide for 24 h in a dose-related manner in children with mite-sensitive bronchial asthma. Suppression was greater in the plastic-adherent antigen-presenting cells than in the T-cells. Oxatomide suppressed the production of interleukin-1alpha induced by Dermatophagoides farinae antigen in plastic-adherent cells. These results indicate that the target cells of oxatomide are antigen-presenting cells and not T-cells. Oxatomide also suppressed interleukin-2 responsiveness in lymphocytes exposed to purified protein derivative, but not in those exposed to concanavalin A. Unlike its effect on cell proliferation, oxatomide potentiated the Dermatophagoides farinae-induced production of interferon-gamma, which was suppressed by stimulation with Dermatophagoides farinae antigen in lymphocytes from the patients. In contrast, production of interferon-gamma induced by concanavalin A was not affected by this drug. These results indicate that oxatomide suppresses interleukin-2 responsiveness of allergen-activated helper T-cells and increases the production of interferon-gamma induced by Dermatophagoides farinae antigen, without causing cell proliferation.

Murine astrocytes express a functional chemokine receptor

Elevated levels of chemokines have been observed in various diseases of the CNS. Little is known, however, about how these chemokines affect parenchymal cells of the CNS. The current studies examine astrocyte chemotaxis to the mouse chemokine macrophage inflammatory protein-1alpha (MIP-1alpha). Murine astrocytes demonstrate directed migration along a chemical gradient in response to 10(-10)-10(-8) M MIP-1alpha. Peak chemotactic responses are noted at 10(-9) M. MIP-1alpha-induced astrocyte migration is specifically inhibitable with pertussis toxin, suggesting a role for Galphai proteins in the signaling process. RT-PCR and in situ hybridization were used to identify expression of the murine CCR1 MIP-1alpha receptor on astrocytes. Astrocytes contain mRNA for CCR1, but messages for CCR4 and the orphan chemokine receptor MIP-1alphaR-like#1 were not detected. The combined results suggest that a functional chemokine receptor is expressed on resident cells of the CNS. We speculate that the interactions of chemokines with astrocytes are involved in inflammatory reactions of the CNS.

Functional expression of the CXC-chemokine receptor-4/fusin on mouse microglial cells and astrocytes

The mRNA for the seven-transmembrane-spanning G protein-coupled receptor fusin/CXCR-4 is expressed in primary mouse astrocyte cultures and the transformed mouse microglial cell line, N9. Cell surface expression of fusin in these cells was confirmed by staining with a polyclonal anti-fusin Ab. The functional capacity of this chemokine receptor was examined by evaluating the calcium responses following stimulation of glial cells with the CXC-chemokine, stromal-derived cell factor-1alpha (SDF-1alpha). Both astrocytes and microglial cells mobilized calcium following stimulation with chemically synthesized SDF-1alpha. SDF-1alpha- and carbachol-mediated calcium responses of astrocytes were partially inhibited by treatment with pertussis toxin (PTx), suggesting receptor coupling to a combination of G alpha(i) and other G proteins. In contrast, the calcium responses of microglial cells to SDF-1alpha were completely PTx sensitive, while responses to carbachol stimulation were PTx resistant. The ability of SDF-1alpha to induce glial cell migration was also examined. Synthetic SDF-1alpha was a potent chemoattractant for mouse microglial cells at ligand concentrations of 10 to 500 ng/ml; peak responses were noted at 100 ng/ml. In contrast, astrocytes did not migrate toward a gradient of SDF-1alpha. The failure of SDF-1alpha to induce astrocyte migration was specific, as another chemokine, macrophage inflammatory protein-1alpha, triggered astrocyte chemotaxis.

Functional expression of the CXC-chemokine receptor-4/fusin on mouse microglial cells and astrocytes

The mRNA for the seven-transmembrane-spanning G protein-coupled receptor fusin/CXCR-4 is expressed in primary mouse astrocyte cultures and the transformed mouse microglial cell line, N9. Cell surface expression of fusin in these cells was confirmed by staining with a polyclonal anti-fusin Ab. The functional capacity of this chemokine receptor was examined by evaluating the calcium responses following stimulation of glial cells with the CXC-chemokine, stromal-derived cell factor-1alpha (SDF-1alpha). Both astrocytes and microglial cells mobilized calcium following stimulation with chemically synthesized SDF-1alpha. SDF-1alpha- and carbachol-mediated calcium responses of astrocytes were partially inhibited by treatment with pertussis toxin (PTx), suggesting receptor coupling to a combination of G alpha(i) and other G proteins. In contrast, the calcium responses of microglial cells to SDF-1alpha were completely PTx sensitive, while responses to carbachol stimulation were PTx resistant. The ability of SDF-1alpha to induce glial cell migration was also examined. Synthetic SDF-1alpha was a potent chemoattractant for mouse microglial cells at ligand concentrations of 10 to 500 ng/ml; peak responses were noted at 100 ng/ml. In contrast, astrocytes did not migrate toward a gradient of SDF-1alpha. The failure of SDF-1alpha to induce astrocyte migration was specific, as another chemokine, macrophage inflammatory protein-1alpha, triggered astrocyte chemotaxis.

[Immunomodulation by TYB-2285 of Dermatophagoides farinae (Df) antigen-induced IFN-gamma and IL-4 production in lymphocytes from children with bronchial asthma]

Effect of TYB-2285 and its metabolites on immune responses by peripheral blood mononuclear cells (PBMC) from children with bronchial asthma was investigated. TYB-2285 and its metabolites have immunosuppressive activity for the proliferation by Df-stimulated patients' lymphocytes. Concanavalin A (Con A)-activated peripheral blood mononuclear cells (PBMC) from the patients were not affected by the same treatment. The results indicate that TYB-2285 and its metabolites are capable of suppressing antigen-induced 3H-thymidine (3H-TdR) uptake but not the response induced by Con A. Interferon-gamma (IFN-gamma) production by Df-stimulated PBMC from patients with active asthma, which was lower than that of normal lymphocytes, were reversed beyond the levels of that in normal subjects. Thus reduced production of IFN-gamma by Df-stimulated patients' lymphocytes was increased by TYB-2285 and its metabolites in a dose-dependent manner. This phenomenon was not observed in lymphocytes from normal subjects. Furthermore, TYB-2285 inhibited IL-4 production induced by Df antigen in asthmatic patients' lymphocytes. Taken, together, TYB-2285 could work as a weak immunosuppressant to modify lymphocytes' responses to allergen in patients with bronchial asthma. These data underscore the potential benefit for the patients with bronchial asthma.

Miscoding properties of model estrogen-DNA adducts in reactions catalyzed by mammalian and Escherichia coli DNA polymerases

The miscoding properties of the model estrogen-derived DNA adducts, N2-[3-methoxyestra-1,3,5(10)-trien-6-yl]-2'-deoxyguanosine (dG-N2-3MeE) and N6-[3-methoxyestra-1,3,5(10)-trien-6-yl]-2'- deoxyadenosine (dA-N6-3MeE), have been explored, using an in vitro experimental system to quantify base substitutions and deletions. Site-specifically modified oligodeoxynucleotides containing a single dG-N2-3MeE or dA-N6-3MeE were prepared postsynthetically and used as templates in primer extension reactions catalyzed by Escherichia coli and mammalian DNA polymerases. When the 3'-->5' exonuclease free (exo-) Klenow fragment of DNA polymerase I was used, dG-N2-3MeE promoted mostly one- and two-base deletions, along with small amounts of incorporation of dAMP, dGMP, and dCMP opposite the lesion. dA-N6-3MeE promoted the incorporation of dTMP opposite the lesion as well as two-base deletions, accompanied by the incorporation of dAMP. Using pol alpha, primer extension reactions were blocked at dG-N2-3MeE; however, dA-N6-3MeE promoted preferential incorporation of dTMP opposite the lesion with small amounts of incorporation of dCMP and deletions. Primer extension reactions catalyzed by pol delta were blocked at these lesions. When pol beta was used, dG-N2-3MeE produced small amounts of incorporation of dAMP and deletions. dA-N6-3MeE promoted preferential incorporation of dTMP, along with incorporation of dCMP and two-base deletions. The miscoding specificities and frequencies varied depending on the DNA polymerase used. These results indicate that estrogen-DNA adducts have miscoding potential.

Ketotifen inhibits allergen-specific T lymphocytes' responses by suppressing antigen presentation with concomitant decrease of HLA-DQ antigen on macrophages

Allergen activates T lymphocytes responsive to interleukin 2 (IL-2) in allergic patients but not in normal individuals. This response was suppressed by anti-allergic agent, Ketotifen (4-(1-methyl-4-piperidylidene)-4H-benzo [4, 5] cyclohepta [1, 2-b] thiophen-10 (9H)-one hydrogen (fumarate). Prolonged culture of antigen-presenting adherent cells impaired the ability to present Dermatophagoides farinae (Df) antigen to T cells, whereas stimulation of adherent cells with recombinant interferon-gamma (IFN-gamma) restored the antigen-presenting capability. The maintained antigen presenting ability of adherent cells treated with IFN-gamma was also suppressed by Ketotifen. Fluorescence activated cell sorter (FACS) analysis disclosed that Ketotifen selectively reduced the expression of HLA-DQ antigen, crucial restriction elements in Df antigen-related responses, on macrophages but not on B cells, even in the presence of IFN-gamma. Collectively, Ketotifen prevented macrophages from inducing allergen-activated T lymphocytes' responsiveness to IL-2 at least in part by decreasing the expression of HLA-DQ antigen.

Cytokine production in children outgrowing hen egg allergy

BACKGROUND

Approximately 40 to 80% of egg-allergic children outgrow egg allergy after 2 to 5 years.

OBJECTIVE AND METHODS

To detail the immunologic mechanisms involved in the development of tolerance to egg proteins, the balance between interleukin 4 (IL4) and interferon-gamma (IFN-gamma) synthesis in patients with active atopic dermatitis allergic to hen egg and in those outgrowing hen egg allergy was evaluated.

RESULTS

A marked increase in IL4 and a decrease in IFN-gamma synthesis by peripheral blood lymphocytes following ovalbumin (OVA) specific in vitro stimulation was observed in active atopic dermatitis. In contrast, OVA-induced IL4 synthesis in patients in remission was comparable to that in normal individuals. An intriguing finding was higher production of IFN-gamma by lymphocytes from ovalbumin-insensitive patients in remission as compared to normal individuals following antigen stimulation, although cell proliferation in OVA-stimulated lymphocytes was reduced in patients during remission.

CONCLUSION

OVA antigen may be capable of inducing a population of Th1-type cells to produce cytokines such as IFN-gamma, resulting in suppression of Th2-type responses, i.e. IL4 secretion. We speculate that the changes in the balance of relevant antigen-induced cytokine synthesis seen in such patients may be causally associated with the improvement in their clinical status.

Induction of allergen-specific IL-2 responsiveness of lymphocytes after respiratory syncytial virus infection and prediction of onset of recurrent wheezing and bronchial asthma

BACKGROUND

In pediatric patients with bronchial asthma and/or atopic dermatitis, peripheral lymphocytes are activated if they are stimulated with the responsible antigen, resulting in induction of responsiveness to IL-2. Because some nursing infants experience recurrent wheezing after respiratory syncytial virus (RSV) infection, attention is being directed to progression of the disease to bronchial asthma.

OBJECTIVE

The study was designed to elucidate the mechanism of the onset of allergic diseases after RSV infection.

METHODS

We examined allergen-specific IL-2 responsiveness induced in lymphocytes in the peripheral blood of infants after infection by RSV. The relationship between the onset of recurrent wheezing and antigen-specific IL-2 responsiveness was analyzed in 25 pediatric patients who could be followed up for 3 years after RSV infection.

RESULTS

Stimulation of lymphocytes with ovalbumin, alpha-casein, and mite (Dermatophagoides farinae) antigens induced significantly higher responsiveness to IL-2 in the RSV-infected infant group than in the healthy infant and disease control groups of the same age. There was no clear correlation between the IgE RAST scores for D. farinae, ovalbumin, and alpha-casein and IL-2 responsiveness. The families of RSV-infected infants had a high incidence of history of allergy (67%), but there was no significant difference in the incidence of patients with positive test results for IL-2 responsiveness between the groups with and without a familial history of allergy. The D. farinae-specific IL-2 responsiveness was significantly increased in the group with the symptom (16 patients) for a value of 1.64 +/- 0.13 (mean +/- SEM) compared with the value of 1.31 +/- 0.21 in the asymptomatic group (9 patients). The incidence of patients with positive test results for IL-2 responsiveness was 68.8% in the symptomatic group and 44.4% in the asymptomatic group. Similarly, the ovalbumin-specific IL-2 responsiveness was significantly increased in the symptomatic group (1.63 +/- 0.17) compared with the asymptomatic group (1.12 +/- 0.26). The incidence of patients with positive test results was 62.5% and 22.2%, respectively. alpha-Casein-specific IL-2 responsiveness was also higher in the symptomatic group than in the asymptomatic group, but the difference was not statistically significant. In the patient groups without RSV infection, on the other hand, the D. farinae-, ovalbumin-, and alpha-casein-specific IL-2 responsiveness in the symptomatic group were all similar to that in the asymptomatic group; no significant increases were detected.

CONCLUSION

The results indicated that after RSV infection, lymphocytes acquire specific susceptibility to D. farinae, a mite antigen, and food antigens, particularly ovalbumin. Hence, it is thought that positive IL-2 responsiveness specific for D. farinae and/or ovalbumin, detected several months after RSV infection, can be a prediction factor for the onset of allergic diseases, such as recurrent wheezing and bronchial asthma.

Reaction of adenine with 6-hydroxyestrogen 6-sulfates: model compounds to demonstrate carcinogenesis by estrogen

To examine carcinogenesis by estrogens, we investigated the reactivity of 6-hydroxyestrogen 6-sulfates. Two epimeric 6-sulfates, pyridinium 3-methoxyestra-1,3,5(10)-trien-6 alpha-yl sulfate (1) and its 6 beta-isomer (2), were synthesized as model compounds and reacted with adenine under mild conditions to give two common products in the ratios of approximately 3:1 and 5:1, respectively. The major product was identified as N6-[3-methoxyestra-1,3,5(10)-trien-6 beta-yl] adenine (10), accompanied with its 6 alpha-isomer (9), by comparison with synthetic specimens. These results imply that, in the metabolism of naturally occurring estrogens, hydroxylation at the C6-position and subsequent sulfoconjugation of the benzylic hydroxyl group may produce sulfates which react with DNA to initiate carcinogenesis.

Mouse astrocytes respond to the chemokines MCP-1 and KC, but reverse transcriptase-polymerase chain reaction does not detect mRNA for the KC or new MCP-1 receptor

Previous studies demonstrated the involvement of astrocytes in the development of astrogliosis, a condition in which these cells undergo proliferation and hypertrophy. To examine whether astrocytes could migrate into lesions, we tested the influence of the murine chemokines MCP-1, KC, TCA3, and MIP-1 beta on migration of cultured neonatal mouse astrocytes. Subnanomolar concentrations of MCP-1 and KC were active chemoattractants indicating that these molecules were effective at physiologic concentrations. Specificity of MCP-1 was demonstrated by antibody inhibition and by the finding that the chemokine MIP-1 beta failed to induce astrocyte migration. The migratory responses were sensitive to pertussis toxin; this finding is consistent with involvement of G protein-coupled receptors. To examine the receptors for these chemokines further, we cloned the mouse homolog of the human MCP-1 receptor from a mouse peritoneal exudate cell cDNA library. The gene had 78% nucleotide sequence homology with the human MCP-1 receptor (the nucleotide sequence of clone 1 encoding the mouse MCP-1 receptor can be obtained from the GenBank database, accession number U56819). However, reverse transcriptase-polymerase chain reaction (RT-PCR) failed to detect message for either the MCP-1 or KC receptors in astrocytes. The combined data suggest that mouse astrocytes use novel receptors to recognize these chemokines.

[Correlation of interleukin-2 (IL-2) responsiveness by egg white-stimulated lymphocytes with hen egg oral provocation test in atopic children]

One hundred and twenty five cases of atopic children such as atopic dermatitis and bronchial asthma were orally provocated with rare hen egg every 20 minutes one by one upto the whole amount. In one week observation 75 cases showed any symptoms of allergy including eruption and exacerbation of atopic eczema in an immediate, late, and/or delayed responses. Frequency of positive egg white-induce IL-2 responsiveness test in patients with positive oral provocation was 90.7% (68 out of 75 cases; sensitivity). That of negative test in patients with negative provocation was 84.0% (42 out of 50 cases; specificity). In contrast, specificity of IgE RAST for egg white were 88.0% comparable to the value of antigen-specific IL-2 responsiveness (AIR) test, but the specificity was lower value (37.3%) for screening the etiological antigens as compared to that of AIR test. High frequency of positive egg white-induced IL-2 responsiveness test was observed over an immediate, late and delayed responses, while low frequency of positive IgE RAST for hen egg was observed largely in patients showing delayed but not immediate response. The results indicate that IgE RAST in this study reflects IgE-mediated immediate type hypersensitivity, whereas AIR test reflects, in addition to immediate responses, late and delayed type hypersensitivity. The combined results suggest that AIR test in hen egg allergy is a useful method in vitro for both screening and determining etiological allergens, and might be able to substitute for provocation test in vivo for which many times, labours, expenses, and patients' risks are required, and to cover IgE RAST which fails to determine etiological allergens in 62.7% of patients with positive oral provocation.

[Suppressive effect of roxithromycin on the induction of IL-2 responsiveness by DF-stimulated lymphocytes from patients with bronchial asthma]

Roxithromycin (RXM) is a new macrolide antibiotics, with anti-allergic properties, the mechanisms of which action has not been well understood. The effect of RXM-treatment on the induction of interleukin 2 (IL-2) responsiveness by Dermatophagoides farinase (Df)-stimulated lymphocytes was studied in patients with bronchial asthma. RXM alone has almost no effect on lymphocyte activation. Patient's lymphocytes treated with 10 to 400 micrograms/ml doses of RXMs failed to generate Df-induced IL-2 responsiveness in a dose-dependent manner. The target cells for suppressive effect of RXM were antigen-presenting cells such as macrophages and dendritic cells rather than responder T cells. PPD-induced IL-2 responsiveness was also suppressed by the treatment, but the Con A-induced response was not. The results suggest that RXM is a slight immunosuppressant to block the induction of IL-2 responsiveness by Df-stimulated patient's lymphocytes, resulting in the interruption of a cytokine cascade of allergic responses.

[Inhibitory effect of Kanpo-medicines: saiboku-to, syouseryu-to, sairei-to on Dermatophagoides farinae antigen-induced IL2 responsiveness in lymphocytes from patients with bronchial asthma and their comparison]

We had previously reported that antigen-induced IL2 responsiveness by lymphocytes can be used to identify etiological allergens and to monitor the clinical activity in atopic diseases. The effect of Kanpo-Medicines; Saiboku-to, Syoseiryu-to, Sairei-to, antiallergic agents, on Dermatophagoides farinae (Df) antigen-induced interleukin 2 (IL2) responsiveness from patients with bronchial asthma was studied and compared among 3 Kanpo-medicines. Allergen-sensitized patient mononuclear cells pretreated with 30-30,000 ng/ml doses of Saiboku-to for 16 hours failed to induce responsiveness to IL2 on stimulation with Df antigen in 8 patients out of 11 (73%). The cells treated with 30 micrograms/ml of Syoseiryu-to also failed to introduce the response in 6 out of 10 (60%) with less frequency compared with Saiboku-to. Sairei-to also suppressed the response on stimulation with a 10 micrograms/ml dose alone in 1 x 10(-3)-1 x 10(-4)ng/ml doses examined in 6 patients out of 17 (35%) with much less frequency and % inhibition. Also Saiboku-to and Sairei-to not Syoseiryu-to inhibited purified protein derivatives (PPD)-induced IL2 responsiveness. However. These agents failed to suppress the Con A-induced IL2 responsiveness. Antigen-presenting adherent cells were more susceptible to any Kanpo-medicines studied rather than IL2-responding T cells except Sairei-to. These results indicated that Kanpo-medicines studied have a weak immuno-suppressive property resulting in inhibiting antigen-induced IL2-responsiveness. Suppressive effects of each Kanpo-medicine seemed to depend on combinations and doses of their elements (Syouyaku). Decreased suppressive effect of higher doses of any Kanpo-medicine was likely to be mitogenic effects of each element on T cells.

T cell mediation of abnormally low production of ovalbumin-specific immunoglobulin A in patients allergic to eggs

Cells producing IgA specific to ovalbumin (OVA) were detected with an assay of plaque-forming cells (PFC). Non-T cells were separated on a polystyrene resin column and were further depleted of B cells that bound sheep erythrocytes (SRBC) by SRBC-rosette sedimentation. The cells were recombined with T cells separated on a polystyrene resin column, stimulated with OVA antigen, and then cultured for 5 d. The number of OVA-specific IgA-PFC from the lymphocytes of infants allergic to hen's eggs (7 +/- 5 per 7 x 10(4) non-T cells, n = 9) was significantly less than that of PFC from lymphocytes of age-matched controls (110 +/- 18 per 7 x 10(4) non-T cells, n = 7) and from those of children with atopic dermatitis who were not allergic to hen's eggs (90 +/- 30 per 7 x 10(4) non-T cells, n = 4). Patients' B cells added to the culture supernatant from OVA-stimulated normal T cells (82 +/- 18 per 7 x 10(4) non-T cells, n = 4) were able to produce the specific IgA to levels comparable to those of normal B cells (92 +/- 9 per 7 x 10(4) non-T cells, n = 6), but the patients' T cells did not cause normal B cells to produce the antibody (8 +/- 2 per 7 x 10(4) non-T cells, n = 4). This indicates that the patients' T cells were less able than were normal T cells to promote the production of OVA-specific IgA-PFC. Until the age of 6 y, the ability of the patients' lymphocytes to produce specific IgA was abnormally low; from that age on, it was normal. At the stage of allergen entry, this transiently low production of OVA-specific IgA may contribute to the onset of allergy to hen's eggs.

[Effect of IL-10 on the mite antigen-induced IFN-gamma production by peripheral blood lymphocytes from individuals with bronchial asthma]

Interferon-gamma (IFN-gamma) production was dose-dependently suppressed by the addition of Dermatophagoides farinae (Df), mite antigen in peripheral blood mononuclear cells from children with bronchial asthma. By contrast, the levels of IFN-gamma did not change on stimulation with Df antigen in the normal lymphocytes from nonallergic individuals not sensitized with mite. Recombinant interleukin 10 (IL-10), when added to the normal lymphocytes, significantly reduced the production of IFN-gamma. Moreover, the decreased synthesis of IFN-gamma in patients' lymphocytes was inversely up-regulated by the treatment with anti-IL-10 antibody. Taken together, results suggest the regulatory role of IL-10 in the secretion of IFN-gamma in Df antigen-driven immune responses.

[Interleukin 1 production by peripheral blood mononuclear cells of children with bronchial asthma in remission]

To analyse the change of the immunological response in the remission state of children with bronchial asthma, we studied the interleukin 1 (IL-1) production of peripheral blood mononuclear cells (PBMC) obtained from children with bronchial asthma sensitized by mite antigen. After PBMC were cultured for 24 hours with Dermatophagoides farinae (Df) or lipopolysaccharide (LPS), the PBMC-derived culture supernatant was estimated for IL-1 alpha and beta by enzyme-linked immunosorbent assay (ELISA). PBMC from some of subjects with active asthma produced IL-1 alpha and beta without any stimulation, but not those from controls or subjects in remission. IL-1 alpha and beta production of PBMC stimulated with Df was observed in all three groups, but IL-1 produced by subjects with active asthma was higher than that produced by subjects in the other two groups. Moreover, when PBMC were incubated with LPS, the secretion of both IL-1 alpha and beta was enhanced. PBMC from patients with active asthma produced both IL-1 alpha and beta in amounts comparable to those produced by PBMC from control subjects, but IL-1 production of PBMC from patients in remission was lower than in the other two groups. IL-1 beta production was about ten times as much as IL-1 alpha. Df-induced IL-1 production of PBMC from asthmatic patients sensitized by mite antigen, which was increased in the active state, was down-regulated in the remission state. Moreover, nonspecific stimuli such as LPS may induce the suppressive factors which down-regulate IL-1 production.(ABSTRACT TRUNCATED AT 250 WORDS)

Pattern of cytokine production by T cells from adolescents with asthma in remission, after stimulation with Dermatophagoides farinae antigen

Children with asthma usually become asymptomatic by the time they reach age 20 y. To clarify the immunologic mechanisms responsible for this phenomenon, we studied patients in remission and others who still had frequent asthma attacks. Patients were grouped by clinical status, and three variables were measured: serum levels of IgE, production of IL4 and interferon (IFN)-gamma, and the activation of T cells induced by Dermatophagoides farinae (Df) antigen. Df-induced activation of T cells (as measured by antigen-induced IL2 responsiveness) or IL2 synthesis itself was induced in patients with active asthma but not in normal subjects. These responses were much weaker in patients in remission. When stimulated by Df antigen in vitro, lymphocytes from patients with active asthma produced much more IL4 than did the cells from normal subjects, and cells from patients in remission produced only a small amount. In contrast, under similar conditions lymphocytes from patients with active asthma produced less IFN-gamma than did the cells from normal subjects. Production of IFN-gamma stimulated by Df antigen was high in patients in remission but not in normal subjects. Thus, upregulated IFN-gamma production after exposure to Df antigen might reduce IL4 secretion, which would suppress IgE production and would improve clinical status. Df antigen may suppress Df-induced allergic responses in patients with asthma in remission.

On the inhibitory effect of C17-sulfoconjugated catechol estrogens upon lipid peroxidation of rat liver microsomes

The antioxidant effect of C17-sulfoconjugated catechol estrogens was examined under ascorbic acid- or NADPH-dependent lipid peroxidation in rat liver microsomes and compared with that of various estrogens and alpha-tocopherol. Among the estrogens tested, a free catechol estrogen such as 4-hydroxyestradiol showed the strongest effect, followed by 2-hydroxyestradiol, 2-methoxyestradiol and estradiol. Next to these steroids, 2-hydroxyestradiol 17-sulfate, followed by 4-methoxyestradiol, 4-hydroxyestradiol 17-sulfate and estrone also showed a strong inhibitory effect, which was greater than that of alpha-tocopherol. Among the C17-sulfates, the guaiacols (2- and 4-methoxyestradiol 17-sulfate) showed a slightly lower effect than alpha-tocopherol, but estradiol 17-sulfate had almost no effect. The antioxidant activity observed in phenolic or guaiacol steroids was considered to be attributed to the catechols produced by their 2- (or 4-)hydroxylation or their O-demethylation, respectively, during the incubation. This was confirmed by identification of the catechols produced from phenolic or guaiacol estrogens and even from the estrogen C3-sulfates. The mechanism of the inhibition by catechols on lipid peroxidation was speculated to involve their activity as radical scavengers, because of their strong reducing activity for 1,1-diphenyl-2-picrylhydrazyl. The above results suggest that C17-sulfoconjugated catechol estrogens (2- and 4-hydroxyestradiol 17-sulfate), although with slightly lower activity than their free catechols, are promising endogenous antioxidants. The physiological role of these estrogen conjugates during pregnancy is discussed.

Regulation of human IgG subclass production by cytokines: human IgG subclass production enhanced differentially by interleukin-6

Peripheral blood mononuclear cells (PBMC) stimulated with pokeweed mitogen (PWM) produced increased IgG when cultured with interleukin-6 (IL-6). IgG subclass analysis showed that the presence of IL-6 during the last half of the culture period enhanced IgG1 and IgG4 production. Enhancement of IgG2 synthesis required the presence of IL-6 solely during the last half of the culture period, whereas enhancement paradoxically was blocked by its presence during the first half. The IgG3-enhancing effect of IL-6 was observed only when IL-6 was present throughout the culture period. The critical role of IL-6 was supported by the inhibition of IgG subclass synthesis by anti-IL-6 antibody. PBMC depleted of cells bearing surface IgG of a particular subclass did not synthesize that subclass. This non-responsiveness, which was not reversed even by an addition of IL-6, indicates that the main action of IL-6 is on the differentiation of committed B cells. In addition, IL-6 triggered T cells to produce significant helper activity. These results indicate that IL-6 enhances IgG subclass production differentially and that its critical role in IgG subclass synthesis is in part mediated by T cells, as well as by its direct action on B cells. These findings should be useful for analysing such immune disorders as IgG subclass deficiencies and autoimmune diseases.

Association of increased numbers of peripheral blood double-negative T-lymphocytes with elevated serum IgG levels in severely handicapped children

CD3+4-8- double negative cells in peripheral blood lymphocytes were examined in 21 severely handicapped children divided into two groups according to serum IgG level. All children were bedridden and were taking multiple anticonvulsants and there were no apparent clinical differences between these two groups. Serum levels of IgG correlated well with percentages of CD3+4-8- double negative lymphocytes in patients of both groups. In comparisons between the two groups, the high IgG group had higher counts of CD3+4-8- double negative lymphocytes in peripheral blood than the normal IgG group. Two distinct types of double negative cells were identified in the patients with high IgG: one had T-cell antigen receptors of gamma delta heterodimers, the other had receptors of alpha beta chains on their surface. As double negative T-cells are reported to have an important role in defence against bacterial infections, the increased numbers of CD3+4-8- T-cells of both phenotypes in the high IgG patients may reflect exposure to repetitive bacterial stimuli or persistent subclinical infection which in many cases, may be undetectable clinically. Moreover, the hyperimmune states shown by the high serum IgG of these patients may result from the appearance of these unique lymphocytes because they are reported to have a helper function for IgG synthesis in vitro. Taken together, the increased numbers of double negative cells in patients with high IgG may reflect activated defence mechanisms and the development of hyperimmune status.

Monoclonal proliferation of Epstein-Barr virus-infected T-cells in a patient with virus-associated haemophagocytic syndrome

Virus-associated haemophagocytic syndrome (VAHS) is a non-neoplastic, generalized histiocytic proliferation disorder showing marked haemophagocytosis associated with systemic viral infection. We describe the case of a 1-year-old girl with Epstein-Barr virus (EBV)-related VAHS, in whom Southern blot analysis showed monoclonal proliferation of bone marrow cells with the EBV genome; detected with the Xho-1 fragment of the latent infection membrane protein genome. EBV serology showed anti-Epstein-Barr virus nuclear associated antigen (EBNA), anti-viral capsid antigen (VCA)-IgG, anti-VCA-IgA elevation and positive EBNA of Sheep red blood cells (SRBC)-rosette-forming bone marrow cells in the late period of her clinical course, indicative of EBV infection. DNA analysis of her bone marrow cells showed monoclonal rearrangement of the T-cell receptor-beta and -gamma chain genes but not of the immunoglobulin heavy chain genes. Those results suggest that EBV may infect T-cells, after which the cells proliferate monoclonally. Repeated administration of epipodophyllotoxin VP-16-213 induced remission, but adrenocortical steroid, vincristine, and cyclophosphamide had no effect on the patient's condition. Ours is a first case report of VAHS showing monoclonal proliferation of EBV-infected T-cells.

Initial events and T cell activation in lymphokine-mediated allergic responses in patients with hen egg allergy

Specific induction of IL2-responsiveness by ovalbumin-stimulated lymphocytes was studied in patients with hen egg allergy. Fluorescence-activated cell sorter analysis of the cells showed that the IL2-absorbing and IL2-responding cells mainly consisted of CD3+2+4+8-45RA+ cells that may act as helper cells for IgE production and/or as effector cells for delayed type hypersensitivity. beta-Chains (P75) of IL2 receptors were involved in ovalbumin-induced IL2 responsiveness of the patients' lymphocytes, whereas the alpha-chains (p55) were expressed on normal lymphocytes stimulated with ovalbumin as well. Adhering mononuclear cells from patients allergic to ovalbumin but not to Dermatophagoides farinae (Df) were pulsed with ovalbumin antigen then added to a T cell-rich population. After five days of culture, we evaluated cell growth for IL-2 sensitivity during an additional 3-day culture in the presence of IL-2. Responder cells from the patients, which were cocultured with ovalbumin-pulsed autologous adhering cells, acquired IL2 responsiveness; whereas, those cultured with Df-pulsed adhering cells did not. This reaction was specific for antigen. The monoclonal antibody to HLA-DQ (Leu 10) and HLA-DP (HLA-DP) frameworks, but not the one to the HLA-DR framework (OKIa1), blocked the antigen presenting cells ability to induce responses. T Cell-rich responder cells depleted of CD4+ cells did not acquire IL2-responsiveness, whereas the depletion of CD8+ cells had no effect. As a whole, the results indicate that DQ-bearing and/or DP-bearing adhering cells have a key function in presenting ovalbumin-antigen to allergen-specific responder T cells that very likely belong to CD4+ subsets.

[Suppressive effect of oxatomide on the induction of IL2 responsiveness by DF-stimulated lymphocytes from patients with bronchial asthma]

Oxatomide is an anti-allergic agent having an anti-histamine effect, and has been widely used for clinical purposes. The effect of oxatomide-treatment on the induction of IL2 responsiveness by Df-stimulated lymphocytes was studied in patients with bronchial asthma. Oxatomide alone has almost no effect on lymphocyte activation. Patient's lymphocytes pretreated with 2 to 2000 ng/ml doses of oxatomides for 24 to 48 hours failed to produce Df-induced IL2 responsiveness in a dose-dependent manner. The target cells for oxatomide's suppressive effect were antigen-presenting cells such as macrophages and dendritic cells rather than responder T cells. PPD-induced IL2 responsiveness was also suppressed by the treatment, but the Con A-induced response was not. The results suggest that oxatomide has a slight immunosuppressive capability to block the induction of IL2 responsiveness by Df-stimulated patient's lymphocytes, resulting in the decreased production of such lymphokines as IL2, IL3, IL4, IL5, in a lymphokine cascade of allergic responses, in addition to inhibition of the degranulation and activation of inflammatory cells such as mast cells/basophils and eosinophils.

[Analysis and regulation of interferon-gamma production by peripheral blood lymphocytes from patients with bronchial asthma]

As with normal lymphocytes, small amounts of interferon-gamma (IFN-gamma) were spontaneously produced by lymphocytes from patients with bronchial asthma, and this bronchial asthma, and this production was markedly enhanced by concanavalin A (Con A) stimulation. Distinct from normal lymphocytes, however, IFN-gamma synthesis from patients' lymphocytes decreased in a dose dependent manner on stimulation with Dermatophagoides farinae (Df) antigen. IFN-gamma-producing cells are defined as being of the CD4+ 45RO+ T cell subset, which failed to produce IFN-gamma in Df-stimulated patients' lymphocytes. As the decreased production of IFN-gamma by antigenic stimulation was exclusively induced by Df antigen, but not by ovalbumin (OVA) or Japanese cedar (JC) antigen, it is concluded that Df antigen specifically suppressed IFN-gamma production in patients' lymphocytes. The IFN-gamma synthesis from normal lymphocytes was suppressed by the addition of IL-4 in a dose dependent manner. Moreover, anti-IL-4 antibody dose dependently enhanced IFN-gamma production from Df-stimulated patients' lymphocytes but not from unstimulated lymphocytes. These results indicate that IFN-gamma production by patients' lymphocytes is suppressed by the endogenous IL-4. Reduced IFN-gamma production in patients' lymphocytes on stimulation with Df antigen may lead to the overproduction of IgE in vivo.

[Analysis of immunosuppressive activity of lecithin-bound iodine (LBI) on antigen-induced IL2 responsiveness in peripheral blood lymphocytes from patients with allergic diseases]

The effect of lecithin-bound iodine (LBI) on antigen-induced IL2 responsiveness, useful in in vitro test for the detection of etiological antigen and disease activity in allergic diseases, was investigated. In peripheral blood mononuclear cells (PBMC) from asthmatic children, LBI suppressed Dermatophagoides farinae (Df)-induced IL2 responsiveness in a dose dependent manner, in a range of 0.01 to 100 micrograms/ml. Similarly, LBI also suppressed ovalbumin (OVA)-induced IL2 responsiveness in PBMC from patients with atopic dermatitis, sensitized with OVA, in concentration of 0.1 to 100 micrograms/ml. Moreover, purified protein derivative (PPD)-induced IL2 responsiveness was equally inhibited by LBI, at doses of between 0.1 and 100 micrograms/ml. However, LBI could not overcome the responses induced by concanavalin A (Con A) until it reached unphysiological concentrations of as high as 100 micrograms/ml. The fact that antigen-induced IL2 responsiveness was suppressed by LBI at concentrations comparable to blood levels of LBI in individuals medicated suggests that LBI is a weak immunosuppressant. IL2-responding T cells were more sensitive to LBI than antigen-presenting cells in Df-induced IL2 responsiveness, although LBI suppressed both cell populations. Taken together, LBI could work as a weak immunosuppressant to inhibit lymphocyte responses to allergen and to improve clinical status in allergic diseases, including bronchial asthma caused by Df and atopic dermatitis provoked by OVA.

[Skin reaction(s) to culture supernatant(s) from Dermatophagoides farinae (Df)-stimulated lymphocytes, and their correlation with Df-induced interleukin 2 responsiveness by lymphocytes from patients with bronchial asthma]

To investigate the inflammatory function of Dermatophagoides farinae (Df)-activated lymphocytes, supernatants from cultures of the lymphocytes were intracutaneously injected into donors' forearms. Injection of the supernatants of Df-stimulated lymphocytes from mite-sensitized atopic individuals with such diseases as bronchial asthma induced a profound inflammatory reaction in the autologous skin, characterized by erythema extending more than 15 mm in mean diameter and edema. The inflammation was at its peak after approximately 20 min, which was followed by gradually re-growing erythema lasting for as long as 24 hours after injection. Supernatants of unstimulated lymphocytes were also capable of inducing the same reaction, indicating the presence of in vivo activated lymphocytes, although the extent of the response was always smaller. The induced response in normal individuals was erythema of less than 15 mm in mean diameter. The supernatants obtained from cultures at 4 degrees C failed to induce such inflammation. The culture supernatants of ovalbumin-restimulated lymphocytes were also incapable of augmenting the response. The combined data show that the production of inflammatory response-inducing factor(s) from Df-stimulated lymphocytes was antigen specific. Significant skin reactions was correlated with the IL2 responsiveness of Df-stimulated lymphocytes. The skin reaction induced by factor(s) derived from Df-stimulated lymphocytes, which might be similar to the bronchial hyperreactivity of patients with bronchial asthma. The in vitro assay for Df-induced IL2 responsiveness by lymphocytes might reflect the in vitro immediate, late and/or delayed type hypersensitivity.

Evidence of conversion of estradiol 17-sulfate to its 2- and 4-hydroxylated catechols by human placental microsomes

When estradiol 17-sulfate (ES) was incubated with human placental microsomes under an NADPH-generating system, 2- and 4-hydroxyestradiol 17-sulfates (2- and 4-OH-ES) formed as the main products. By kinetic experiments, the apparent Km values of 44.0 and 360 microM and apparent Vmax values of 236 and 140 pmol/mg protein/10 min were obtained for the 2- and 4-hydroxylation, respectively. The results indicate that human placental microsomes have fairly high 2- and 4-hydroxylase activities toward ES. This paper describes the formation of 2- and 4-OH-ES and speculates on their physiological role during pregnancy.