Shinji Shinoda

The role of T lymphocytes in patients with food-sensitive atopic dermatitis

The role of T lymphocytes was assessed in patients with food-sensitive atopic dermatitis (AD). T lymphocytes plus monocytes responded well to ovalbumin or bovine serum albumin (BSA) in children with AD who were sensitive to hens egg or cows milk compared with healthy children and children with immediate allergic symptoms who are sensitive to hens egg or cows milk. The responding cells were shown to be predominantly CD4+ T lymphocytes. Interleukin-2 activity and interferon-gamma concentrations in culture supernatants of ovalbumin-stimulated peripheral blood mononuclear cells (PBMCs) from patients with AD who were sensitive to hens egg were significantly higher than those of healthy children and patients sensitive to hens egg with immediate symptoms. Expression of Fc epsilon R II on B lymphocytes in cultures of ovalbumin-stimulated PBMCs from patients with AD was significantly higher than that of healthy children, but it tended to be lower than that of patients with immediate symptoms. These results suggest that, in patients with AD who are food sensitive, CD4+ T lymphocytes stimulated by food antigens secrete lymphokines such as interleukin-2 and interferon-gamma that are secreted from TH1 clones in mice, and express Fc epsilon R II on B lymphocyte that is induced by interleukin-4 secreted from TH2 clones in mice. Taken together, cell-mediated immunity may also occur in addition to IgE-mediated hypersensitivity in patients with food-sensitive AD.

Effect of elimination diets on food-specific IgE antibodies and lymphocyte proliferative responses to food antigens in atopic dermatitis patients exhibiting sensitivity to food allergens

Peripheral blood mononuclear cells (PBMCs) from patients with atopic dermatitis (AD) selected as being sensitive to hens egg or cows milk responded to food antigens, ovalbumin, or bovine serum albumin, with significantly enhanced DNA synthesis compared with the DNA synthesis in PBMCs from nonatopic control subjects and food-sensitive patients with immediate symptoms. Patients were treated with elimination diets. Symptoms of AD had been in remission during elimination diets. The levels of specific IgE antibodies to hens egg or cows milk decreased during elimination diets in patients with positive radioallergosorbent test (RAST). In patients with negative RAST, specific IgE antibodies remained negative during elimination diets. The proliferative responses of PBMCs to food antigens also decreased during elimination diets in patients with proliferative responses before elimination diets. Taken together, specific IgE antibodies to food antigens are useful indexes of the effect of elimination diets in food-sensitive patients with AD and positive RAST, and proliferative responses of PBMCs to food antigens are useful indexes of the effect of elimination diets in food-sensitive patients with AD and proliferative responses of PBMCs.

Identification of β-lactoglobulin-derived peptides and class II HLA molecules recognized by T cells from patients with milk allergy

Background Cows milk allergy impairs the health and development of many infants since it deprives them of adequate nutrition. Cows milk fractions contain many allergens, and β‐lactoglobulin (BLG) is one of the major allergens.

Predictive values of cord blood IgE and cord blood lymphocyte responses to food antigens in allergic disorders during infancy

Proliferative response of cord blood lymphocytes stimulated twice by food antigens and cord blood IgE concentration were measured in 131 full-term newborn infants for the prediction of allergic disorders. Through the follow-up study for 2 1/2 years, the value of stimulation index in proliferative response of cord blood lymphocytes to ovalbumin or bovine serum albumin was greater than 1.5 in 17 (sensitivity 53.1%) of 32 infants in whom allergic disorders developed and less than 1.5 in 81 (specificity 81.8%) of 99 infants who had no allergic disorders (cutoff limit of stimulation index 1.5). The sensitivity was increased (71.9%) by the combination of the cord blood IgE concentration (cutoff limit 1.0 IU/ml) and proliferative response of cord blood lymphocytes to food antigens (cutoff limit of stimulation index 1.5). The combination of the cord blood IgE concentration and proliferative response of cord blood lymphocytes to food antigens is useful for the prediction of allergic disorders. Interleukin-2 production of cord blood lymphocytes stimulated with food antigens was also measured in 24 newborn infants. Interleukin-2 activity in culture supernatants of ovalbumin- or bovine serum albumin-stimulated cord blood lymphocytes correlated well with proliferative response of cord blood lymphocytes to ovalbumin or bovine serum albumin.

Acute cerebellitis in primary human herpesvirus-6 infection

Acute cerebellitis has been described in infections caused by many kinds of pathogens, but as yet has not been described in human herpesvirus-6 (HHV-6) infection [11]. We report here a case of acute cerebellitis during primary HHV-6 infection. A 2.5-year-old girl was admitted to a local hospital because of a 3-day history of high fever and generalised tonic convulsions which occurred four times on the 3rd day. Physical examination showed a normally developed alert infant with truncal ataxia. A cranial CT scan was normal. Her CSF showed normal concentrations of protein and glucose and no pleocytosis. In the evening of the day of admission, she had five episodes of generalised tonic convulsions with high fever and became irritable, but was well oriented. Skin erythema on the face, trunk, and extremities clearly appeared the next morning and she became drowsy; she was then transferred to our hospital. On admission, she was unconscious and showed a withdrawal movement, crying briefly in response to pain (Glasgow coma scale E3V2M4). Both pupils were equal in size and prompt in light reflex and her tendon reflexes were normal. There was no optic oedema. There was a rubella-like erythema on her face, trunk, and extremities without vesicles or petechiae. Laboratory data, including levels of ammonia, lactate and pyruvate, were normal except that of serum CK (1711 IU/l). Analysis of CSF showed 402 leukocytes/mm (segmented 322, mononuclear 80), a glucose level of 68 mg/dl and a protein level of 79 mg/dl. No oligoclonal IgG bands or myelin basic protein were observed. Neuron specific enolase (NSE) in CSF was elevated (130 ng/ml; control mean 13.1 ng/ml). Her EEG showed normal findings. MRI on the 5th day of illness demonstrated a diffuse hyperintensity in the cerebellum based on the diffusion-weighted sequence but not obvious on the T1or T2-weighted images (Fig. 1a). Brain single photon emission CT (SPECT) by ECD on the same day showed a marked hyperperfusion in the bilateral hemispheres of the cerebellum (Fig. 1b,c). With the diagnosis of acute encephalitis, predominantly in the cerebellum, she was treated with mannitol, dexamethasone, and phenobarbital. Acyclovir (10 mg/kg per dose) was used every 8 h for 2 weeks. She did not experience any convulsions after the therapy had started and she recovered her full consciousness within 1 week. After this significant recovery, severe cerebellar dysfunctions such as ataxia and dysmetria were more obvious, but excellent improvement was achieved within 1 month without any sequelae. The hyperintensity on MRI and hyperperfusion on SPECT in the cerebellum disappeared with clinical improvement (Fig. 1d,e,f). In addition to these radiological findings, MRI on admission demonstrated abnormal high intensities at the splenium of the corpus callosum on T2and diffusionweighted images, which disappeared 72 h after the first MRI [6]. Titres of serum immunoglobulins for HHV-6 (fluorescent antibody method) were significantly elevated during the illness (on the 6th day of illness: IgG <1:10, IgM 1:10; on the 25th day of illness: IgG 1:320, IgM 1:20), while those in CSF were not (on the 6th day of illness: IgG <1:10, IgM <1:10; on the 25th day of illness: IgG <1:10, IgM <1:10). The titres against the many other pathogens which can cause erythema or encephalitis including HHV-7, herpes simplex, EpsteinBarr virus, varicella zoster virus, rubella virus, measles virus, parbovirus, enterovirus 71, influenza virus, and Mycoplasma pneumoniae were not significantly elevated. Cultures of CSF did not reveal any viral pathogen. PCR analysis of CSF with specific primers for the U31 gene of HHV-6 (forward primer: 5’-TGCACCACCTCTCTGCTTATAAC-3’, reverse primer: 5’-CTAATTGCCGTAGCGTGAGAAC-3’) and the sequencing of the Eur J Pediatr (2003) 162: 801–803 DOI 10.1007/s00431-003-1287-7

Autonomic regulation after exercise evidenced by spectral analysis of heart rate variability in asthmatic children

BACKGROUND Bronchial asthma is associated with abnormal autonomic nervous function in childhood. Exercise is one of the most common precipitating factors of acute asthmatic crises although the exact mechanism of autonomic regulation in asthmatic children after exercise is unclear. OBJECTIVE The aim of this study was to investigate the features of autonomic regulation after exercise in asthmatic and control children. METHODS Pulmonary function tests and heart rate variability spectral analysis were performed in 15 asthmatic children and 7 control children (age 6 to 15 years) during and after an exercise challenge. RESULTS The maximum % fall of forced expiratory volume in 1 second (FEV1) was significantly greater (P < .01) in asthmatic subjects (9.1 +/- 5.1%) than in normal control subjects (1.0 +/- 2.5%). The high frequency band (HF) amplitude, an index of cardiac vagal tone, 5 minutes after exercise was significantly higher (P < .05) in the asthmatic subjects (14.4 +/- 7.9 msec) than in control subjects (5.9 +/- 2.6 msec). Furthermore, the difference in the HF amplitude between the control group and the exercise-induced asthma group was significant both 5 minutes (P < .01) and 10 minutes (P < .05) after challenge. There was a significant correlation (P = .565, P = .0165) between HF amplitude 5 minutes after exercise and the magnitude of the decrease in FEV1. On the other hand, no significant difference was observed in the low frequency band amplitude between the controls and the asthmatic subjects. The ratio of low frequency to high frequency power, which is suggested to correlate with cardiac sympathetic activity, did not differ between the two groups. CONCLUSION These findings suggest that autonomic nervous activities, particularly vagal response after exercise, in asthmatic children is different from that in control children.

Pulmonary hemosiderosis with hypersensitivity to buckwheat

BACKGROUND Adverse reactions after ingesting buckwheat are known to be IgE-mediated. Further, hypersensitivity reactions may be involved in some patients with pulmonary hemosiderosis related to cow milk sensitivity. We, however, encountered a patient with pulmonary hemosiderosis related to buckwheat protein without high levels of buckwheat-specific IgE antibodies. OBJECTIVE The aim of this study was to investigate the mechanisms. METHODS RAST for anti-buckwheat IgE, skin prick test, skin patch test, and proliferative responses of peripheral blood mononuclear cells to buckwheat were investigated in this patient. RESULTS RAST values for buckwheat protein were negative, and skin prick test for buckwheat protein also gave negative results. On the other hand, skin patch testing for buckwheat protein elicited positive responses. Further, peripheral blood mononuclear cells of our patient responded to buckwheat protein. CONCLUSIONS Our patient had pulmonary hemosiderosis related to non-immediate buckwheat protein hypersensitivity.

Improvement of food‐sensitive atopic dermatitis accompanied by reduced lymphocyte responses to food antigen following natural measles virus infection

Five patients with atopic dermatitis (AD) who were sensitive to hens egg were observed before and after natural measles virus infection. Within 4 weeks of natural measles virus infection, the eczematous lesions clearly improved in four of the five patients in whom neither offending foods were eliminated, nor anti‐allergic drugs, systemic steroids and steroid ointment administered. This was accompanied by reduced proliferative responses of peripheral blood mononuclear cells (PBMCs) to ovalbumin (OA). Another patient showed a transient improvement of AD symptoms, from severe to mild, and thereafter returned to severe accompanied by increased proliferative responses of PBMCs to OA. Radioallergosorbent test (RAST) scores for hens egg in all five patients did not change in each level in each patient, except the transiently decreased RAST scores for hens egg in one patient, after the infection. Thus, in patients with AD who are sensitive to food, the improvement of AD symptoms that appeared within 4 weeks of natural measles virus infection was related to reduced proliferative responses of PBMCs to the food antigen following the infection.

Accelerated expression of secreted α-chain gene in anaphylactoid purpura

The mechanisms of the elevation of serum IgA levels in anaphylactoid purpura were investigated. Serum IgA levels were significantly elevated within 2 weeks (5 to 14 days for all 12 patients) after onset in patients with anaphylactoid purpura. Serum IgM and IgG were not elevated. Although the percentages of surface IgA-bearing cells were not increased in the patients, the numbers of IgA-secreting cells within 2 weeks after onset in the patients with anaphylactoid purpura were significantly higher than those of controls. In northern blot analysis on lymphocytes, the secreted α (αs)-chain gene was well expressed compared with the membrane-bound α (αm)-chain gene, within 2 weeks after the onset of anaphylactoid purpura. Therefore, stimulation by a certain agent or a certain immune response may accelerate expression of the αs-chain gene in anaphylactoid purpura.

The response of bovine beta-lactoglobulin-specific T-cell clones to single amino acid substitution of T-cell core epitope

Cow’s milk is one of the most common food allergens in the first year of life, with approximately 2.5% of infants experiencing an allergic reaction to it. Beta‐lactoglobulin (BLG) is one of the major allergens in cow’s milk. Previously, we reported that four of six T‐cell clones (TCC) which were established from cow’s milk allergy patients recognized BLGp97‐117 as the core sequence and also recognized BLG in association with the human leucocyte antigen (HLA)‐DRB1*0405 allele. Using two of these four TCCs, we evaluated the T‐cell response to BLG peptides with single amino acid substitution or deletion and identified BLGp102‐112 as the minimum essential region in BLGp97‐117. In the alanine‐scan assay, the proliferative responses of TCCs to pE108A disappeared, and the proliferative responses of TCCs to pC106A decreased. In the analog peptide proliferation assay, pY102S had retained some T‐cell response to the two TCCs. Collecting these results, we propose a motif for the interaction between the HLA‐DRB1*0405 allele and antigen peptide, and suggest that BLGp105‐108 are important residues to retain the TCR/BLG‐peptide/HLA complex. pY102A and pY102S are partial agonists for the T‐cell receptor. These peptides might be considered as candidate peptides for the modification of the T‐cell response to BLG in cow’s milk allergy.