Decreased Basophil Activation against House Dust Mite after Japanese Cedar Pollen Subcutaneous Immunotherapy: A Retrospective Study

BACKGROUND

Allergen-specific immunotherapy (AIT), an established treatment for allergic diseases, prevents the development of other allergic manifestations. Although the mechanisms remain unclear, AIT has been shown to reduce basophil activation (BA) against nontarget allergens.

OBJECTIVES

The aim of this study was to assess immunological changes in Dermatophagoides farinae (Der f) after Japanese cedar pollen (JCP)-based subcutaneous immunotherapy (SCIT) monotherapy.

METHOD

The data of 16 patients (age: 6-37 years) with JCP-induced allergic rhinitis who were sensitive to Der f (serum Der f-specific immunoglobulin E [IgE] level >0.34 kUA/L) and received JCP-based SCIT for 5 years were reviewed retrospectively. BA by Der f and JCP extracts and serum-specific IgE and immunoglobulin G4 (IgG4) levels against these allergens were evaluated before and after completing 5 years of JCP-based SCIT monotherapy.

RESULTS

The areas under the dose-response curves of BA by Der f and JCP extracts were significantly reduced (p = 0.02 and p = 0.002, respectively). JCP-specific IgE levels decreased and JCP-specific IgG4 levels increased significantly (p < 0.001 for both), whereas Der f-specific IgE and IgG4 levels did not change significantly.

CONCLUSIONS

JCP-based SCIT monotherapy reduced Der f-specific BA. These findings suggest that JCP-based SCIT has the potential to modulate immune response toward nontarget allergens.

Allergenicity of partially hydrolyzed whey and casein formulas evaluated by ImmunoCAP inhibition assay and basophil activation test

Background

When exclusive breastfeeding is not possible, partially hydrolyzed formula (PHF) is often used as a starter formula for infants. Some children develop allergic symptoms, including anaphylaxis, after the first intake of cow protein. Therefore, the tolerability of PHF in infants with cow's milk allergy (CMA) is important information. Partially hydrolyzed whey formula (PHWF) is well characterized, but those containing both whey and casein are also available. We evaluated the characteristics of two whey and casein PHFs, PHF1 and PHF2, in vitro and ex vivo, and compared them with a PHWF, PHWF1.

Methods

Residual antigenicity of β-lactoglobulin (β-LG) and casein in the formulas was measured using ELISA. The molecular weight profile was determined using high-pressure liquid chromatography. IgE reactivity and allergenic activity of the formulas were evaluated by ImmunoCAP inhibition assay and by basophil activation test using blood from patients with CMA, respectively.

Results

All the participants (n = 10) had casein-specific IgE. The antigenicity of β-LG in PHF1 was similar to that in PHWF1, but it was slightly higher than that in PHWF1 for casein. PHF1 had a higher IgE reactivity than PHWF1. However, PHF1 and PHWF1 had a similar ability to activate basophils. PHF2 had lower antigenicity of casein and β-LG, IgE reactivity and basophil activation than PHWF1.

Conclusion

These results suggest that the tolerability of PHF1 and PHF2 in patients with CMA is similar to and higher than that of PHWF1, respectively, and that the degree of IgE binding to PHFs does not necessarily correspond to basophil activation.

Generalized allergic reaction in response to exercise due to strawberry gibberellin-regulated protein: a case report

Background

The Rosaceae family includes fruits, such as peach, apple, Japanese apricot, cherry (Prunoideae subfamily), and strawberry (Rosoideae subfamily). The allergens responsible for Rosaceae fruit allergies have been reported to include Bet v 1 and profilin, which mainly cause oral symptoms, and lipid transfer protein (LTP). Recently, gibberellin-regulated protein (GRP) has been identified as an allergen that induces generalized symptoms in peach-, orange-, and plum-related allergies. Most patients with food allergies induced by GRP show allergic symptoms accompanied by cofactors, such as exercise or drugs. To date, there are very few reports of generalized symptoms induced by strawberry.

Case presentation

We evaluated the reactivity of strawberry GRP in a 15-year-old boy who was confirmed to have generalized symptoms induced by strawberry with exercise using an oral food challenge test (OFCT). The patient’s serum exhibited a strong positive reaction to strawberry GRP but not to peach GRP or peach LTP. The patient’s basophils reacted to strawberry and peach GRP but not to peach LTP.

Conclusions

Strawberry GRP may be a causative component for strawberry with exercise-induced generalized symptoms in this patient. This is the first study to investigate the role of GRP in strawberry with cofactor-induced allergic symptoms. Further epidemiological and clinical researches are necessary to improve diagnostic and therapeutic approaches for patients with strawberry allergy.

Case of a 6-year-old boy with anaphylaxis induced by erythritol with positive skin prick test and negative basophil activation test

Erythritol is widely used as an additive in foods and pharmaceuticals. We present the case of a 6-year-old boy who developed an allergy to erythritol. He showed a positive skin prick test result and a negative basophil activation test result. In cases involving allergens with low molecular weights, the test results should be carefully interpreted.

Kawasaki disease presented with status epilepticus and diffusion MRI abnormalities in the subcortical white matter

BACKGROUND

Kawasaki disease (KD) is an acute, self-limited vasculitis of unknown etiology that occurs predominantly in infants and young children. Encephalitis/encephalopathy is an extremely rare complication of KD.

CASE

A previously healthy 8-month-old Japanese boy had a prolonged seizure after febrile illness for one day. On the fourth day, he had bilateral nonexudative conjunctivitis, changes in the extremities, rash and induration at the Bacillus Calmette-Guerin inoculation site. He was diagnosed with incomplete KD and treated with immunoglobulin. On the fifth day, he had cluster seizures. Brain magnetic resonance imaging (MRI) showed restricted diffusion in the left subcortical white matter, which was consistent with acute encephalopathy with biphasic seizures and late reduced diffusion (AESD). He was treated with controlled normothermia, pulseddose methylprednisolone, continuous infusion of midazolam, and edaravone. On the tenth day, he had a recurrent fever and was treated with a second course of immunoglobulin. Subsequently, he had defervescence, and the abnormal signal detected in the MRI disappeared. At the age of 11 months, he had normal growth and development for his age by the Denver Developmental Screening Test.

CONCLUSION

It is necessary to consider AESD as the differential diagnosis of prolonged seizure in infants with KD. Brain MRI led to early diagnosis and intervention in our patient. The neurological prognosis of our patient was relatively good, but the prognosis of KD with AESD is unknown. To clarify this, further case accumulation is warranted.

Tolerability of partially and extensively hydrolysed milk formulas in children with cow's milk allergy

BACKGROUND AND OBJECTIVES

The safety and tolerability of hydrolysed cow's milk protein-based formulas, particularly partially hydrolysed formulas (pHFs), in children with cow's milk allergy (CMA) remain poorly understood. We evaluated the tolerability of hydrolysed cow's milk-based formulas in children with CMA.

METHODS AND STUDY DESIGN

A three-period double-blind crossover evaluation compared the allergic tolerance against three dietary cow's milk-based formulas: extensively hydrolysed cow's milk formula (eHF), pHF, and regular cow's milk formula (rCMF). The primary outcome was the rate of tolerance against a maximum of 20.0 mL of formula.

RESULTS

Controlled food challenges were performed in 25 children (18 boys; 7 girls) with a median age of 4.25 years (range: 1-9 years) diagnosed with CMA. The median cow's milk-specific immunoglobulin E level was 31.9 UA/mL (range: 1.16-735 UA/mL). The tolerance rate ratios for rCMF were lower than those for pHF (2 vs 16; p<0.01) and eHF (2 vs 22; p<0.01). The allergic symptom scores induced by intake of pHF and eHF were significantly lower than those of rCMF (p=0.01 and p<0.01, respectively), and the pHF and eHF scores were not significantly different.

CONCLUSIONS

Compared to rCMF, the partially and extensively hydrolysed whey and casein formulas evaluated in this study were better tolerated and therefore safer for children with CMA. Although further confirmation from additional centres is needed, our findings suggest the use of pHF in patients with mild CMA. Some children with CMA react to hydrolysed formulas; therefore, food challenge tests in these children should be undertaken with caution.

Hyponatremia secondary to severe atopic dermatitis in early infancy

BACKGROUND

Infants with atopic dermatitis who developed hyponatremia and hyperkalemia with raised aldosterone have been repeatedly described in the Japanese-language literature, but similar reports from other countries are scarce.

METHODS

We collected reports of atopic dermatitis complicated with hyponatremia (≤130 mEq/L), written either in English or in Japanese, to delineate the characteristics and to elucidate the pathophysiology of this condition.

RESULTS

Of a total of 36 patients, 35 were Japanese. All patients were infants younger than 9 months. Mean height SD score (SDS) at presentation was -2.1 ± 1.4 (n = 25), with mean body mass index 14.1 ± 1.7 kg/m² (n = 28). Mean sodium was 120.7 ± 6.1 mEq/L. While 28 patients had hyperkalemia, seven patients had normokalemia. Elevated aldosterone was documented in 15 patients. Nutrition mainly with breast-feeding (97%), parental refusal of steroid ointment (77%), and the association of hypoalbuminemia (73%) were frequent findings. Diminished urinary sodium was verified in all 12 patients tested, indicating that sodium loss from the skin exudates, with limited supply of sodium from breast milk, is the primary cause of hyponatremia. Hyperkalemia seems to result from decreased delivery of sodium to the distal nephron and from the mechanism of the so-called "aldosterone paradox", which inhibits potassium secretion. In addition, physiological aldosterone insensitivity during infancy, low muscle volume, and impaired Na⁺ ,K⁺ -ATPase function due to protein deficiency seems to exaggerate the hyperkalemia.

CONCLUSIONS

Hyponatremia secondary to severe atopic dermatitis is an age-dependent manifestation, elicited by inappropriate treatment that leads to sodium loss from the damaged skin and resultant hyperkalemia via multifaceted mechanisms.

Evaluation of serum IgE in peach-allergic patients with systemic reaction by using recombinant Pru p 7 (gibberellin-regulated protein)

BACKGROUND

Lipid transfer protein (LTP) is a major fruit allergen. It has, however, recently been revealed that the systemic reaction in peach-allergic patients is related not only to LTP (Pru p 3) but also to gibberellin-regulated protein (Pru p 7). We investigated recombinant Pru p 7 (rPru p 7) for its potential use in worldwide standardization for the diagnosis of peach allergy.

METHODS

Natural Pru p 7 (nPru p 7) was purified from peach crude extract using a monoclonal antibody affinity column. Complementary DNA for Pru p 7 was cloned and expressed in Escherichia coli and Pichia pastoris. Serum immunoglobulin (Ig) E in peach-allergic patients was examined by enzyme-linked immunosorbent assay (ELISA) using nPru p 7 and rPru p 7 (E. coli product: erPru p 7 and P. pastoris product: prPru p 7).

RESULTS

Peach-allergic patients (n=27) were diagnosed and categorized into oral reaction (n=10) or systemic reaction (n=17). The nPru p 7 positivity based on serum IgE levels was 52% in the systemic-reaction group and 0% in the oral-reaction group (P<0.05). In the systemic-reaction group, there was no significant difference in reactivity between nPru p 7 and prPru p 7, but the reactivity of erPru p 7 was significantly lower than those of nPru p 7 and prPru p 7 (P<0.05).

CONCLUSIONS

We found that prPru p 7 exhibited reactivity in ELISA comparable to that of nPru p 7 for the diagnosis of peach allergy with systemic reaction.

Oral Immunotherapy Using Partially Hydrolyzed Formula for Cow's Milk Protein Allergy: A Randomized, Controlled Trial

BACKGROUND

Partially hydrolyzed cow's milk protein-based formula (pHF) possesses low allergenicity. Here, we investigate the safety and efficacy of oral immunotherapy using pHF for children with cow's milk protein allergy (CMPA).

OBJECTIVES

A randomized, double-blind, controlled single-center trial was conducted to evaluate the efficacy and safety of pHF oral immunotherapy in children with CMPA.

METHODS

Participants were randomized into double-blind pHF-pHF and extensively hydrolyzed cow's milk protein-based formula (eHF)-pHF groups. During this phase, the pHF-pHF group received pHF and the eHF-pHF group received eHF. During the open phase, all participants received pHF. The primary end point was a change in thresholds between baseline and the end of the first phase. Secondary end points were changes in thresholds between baseline and the end of the second phase, and casein-specific immunoglobulin (Ig)E, IgG4, and basophil activation.

RESULTS

Twenty-five children, aged 1-9 years, were randomized into pHF-pHF and eHF-pHF groups. The threshold between baseline and the end of the first phase was significantly elevated in the pHF-pHF group (p = 0.048), but not in the eHF-pHF group. The threshold between other phases did not change significantly in either group. There were significant decreases in casein-specific IgE antibody levels between baseline and the second phase in the eHF-pHF group (p = 0.014). No participants suffered systemic allergic reactions requiring adrenaline or systemic corticosteroids after receiving the formulas.

CONCLUSIONS

The results of this trial suggest that, in children with CMPA, tolerance to cow's milk might be safely enhanced by intake of pHF, relative to that of eHF.

Multicolor flow-cytometric analysis of milk allergen-specific T-helper type 2 cells revealed coexpression of interleukin-4 with Foxp3

BACKGROUND

Allergen-specific T-helper type 2 (TH2) cells play an important role in the development of allergic inflammation; however, investigations of the properties of allergen-specific T cells have been challenging in humans. Despite clear evidence that forkhead box p3 (Foxp3) is expressed in conventional effector T cells, its function has remained unknown.

OBJECTIVE

To characterize allergen-specific TH2 cells in milk allergy, with particular focus on the expression of Foxp3.

METHODS

Twenty-one children with milk allergy and 11 children without milk allergy were studied. Peripheral blood mononuclear cells from subjects were stimulated with milk allergen for 6 hours and analyzed using multicolor flow cytometry to identify CD154(+) allergen-specific T-helper cells. Simultaneously, the expression of intracellular cytokines and Foxp3 was analyzed.

RESULTS

The milk allergy group had significantly larger numbers of milk allergen-specific interleukin (IL)-4- and IL-5-producing CD4(+) T cells than the control group. Subjects in the milk allergy group had significantly more CD154(+)CD4(+) IL-10-producing cells and CD154(+)Foxp3(+)CD4(+) cells than those in the control group. In addition, the number of milk allergen-specific CD154(+)Foxp3(+)CD4(+) cells strongly correlated with that of CD154(+)IL4(+)CD4(+) cells. Bcl-2 expression in CD154(+)IL-4(+)Foxp3(+) T-helper cells was significantly lower compared with that in total CD4 cells.

CONCLUSION

Increased numbers of IL-4-producing allergen-specific T-helper cells were found in patients with milk allergy. In addition, Foxp3 was coexpressed with IL-4 in allergen-specific TH2 cells from patients. This coexpression was associated with lower Bcl-2 levels and could contribute to the phenotype and function of TH2 cells.

Japanese cedar pollen-based subcutaneous immunotherapy decreases tomato fruit-specific basophil activation

BACKGROUND

Some patients with Japanese cedar pollen (JCP)-induced allergic rhinitis develop pollen-food allergy syndrome (PFAS) as a reaction to tomato fruit. Pollen allergen-specific subcutaneous immunotherapy (SCIT) is reportedly beneficial for some associated food allergies; however, the reported changes in food allergen-specific immunoglobulin (Ig)E and IgG4 levels are inconsistent. Here, we investigated immunologic reactivity to tomato fruit after JCP-based SCIT.

METHODS

Twenty-three children (aged 6-17 years) with JCP-induced allergic rhinitis and sensitized to tomato (serum tomato fruit-specific IgE level >0.34 UA/ml) received JCP-based SCIT. Basophil activation by tomato and JCP extracts and serum-specific IgE and IgG4 levels against these allergens were determined before and after 4 or 5 months of maintenance SCIT. Basophil activation was assessed by monitoring CD203c upregulation on flow cytometry.

RESULTS

JCP-based SCIT significantly reduced the basophil activation caused by tomato fruit (p = 0.03) and JCP (p < 0.001) extracts. JCP-specific IgG4 levels markedly increased after SCIT (p < 0.001), whereas tomato fruit-specific IgG4 levels did not. After SCIT, no significant changes were observed in specific IgE levels for tomato fruit (p = 0.11) or JCP (p = 0.19).

CONCLUSIONS

Tomato fruit-specific basophil activation decreases after JCP-based SCIT, suggesting that it is efficacious in relieving and preventing the symptoms of PFAS in patients with JCP-induced allergic rhinitis.

Allergen analysis of sea urchin roe using sera from five patients

BACKGROUND

Sea urchin roe can cause anaphylactic reactions the first time they are consumed; therefore, careful clinical attention should be paid to their effects. However, no previous study has examined the allergens in sea urchin roe using sera from more than one patient. We attempted to identify sea urchin allergens using sera from 5 patients with sea urchin allergies.

METHODS

We enrolled 5 patients with relevant medical histories, positive results on a skin prick test and/or a food challenge test, and high levels of sea urchin-specific IgE in an enzyme-linked immunosorbent assay. We performed SDS-PAGE, immunoblotting, immunoblot inhibition, and N-terminal amino acid sequence detection.

RESULTS

Ten protein bands ranging from 18 to 170 kDa were detected in more than 2 patients' sera. In immunoblotting, the protein band for the 170-kDa major yolk protein was recognized by 4 of the 5 sera. Furthermore, the reaction between IgE and the protein band for egg cortical vesicle protein (18 kDa) was inhibited by the addition of salmon roe extract.

CONCLUSION

Major yolk protein was confirmed to be one of the main allergens in sea urchin roe. In addition, egg cortical vesicle protein (18 kDa) was demonstrated to be an important protein for cross-reactivity with salmon roe.

Acute eosinophilic pneumonia occurring in a dedicator of cytokinesis 8 (DOCK8) deficient patient

Dedicator of cytokinesis 8 (DOCK8) deficiency is an autosomal recessive type of combined immunodeficiency with elevated IgE. In this report, we describe a Japanese girl of non-consanguineous family suffering from acute eosinophilic pneumonia (AEP) as a presenting feature of DOCK8 deficiency. Although AEP was self-limiting, consecutively experienced recurrent respiratory infections, severe atopic dermatitis, and vulnerability to viral infections, prompted us to evaluate the possibility of DOCK8 deficiency. Immunological assessments demonstrated decreased IgM, increased IgE, T lymphocytepenia, especially in CD4 T cells, decreased PHA blastogenesis, and decreased CD27(+) CD19(+) memory B cells. Western blotting revealed the absence of DOCK8 protein. Investigation of genomic DNA by multiplex ligation-dependent probe amplification (MLPA) revealed a heterozygous large deletion of 77 kb spanning from intron 5 to exon 22. DOCK8 cDNA sequencing revealed a nonsense mutation at position 740 (E740X). As far as we know, this is the first Japanese case of DOCK8 deficiency.

Effect of Japanese cedar specific immunotherapy on allergen-specific T(H)2 cells in peripheral blood

BACKGROUND

The involvement of a shift from TH2 to TH1 responses in peripheral blood in pollen subcutaneous immunotherapy (SCIT) has been contentious, partly because of difficulties analyzing antigen-specific TH cells.

OBJECTIVES

To use recent technical advances to establish a more direct and simple method to analyze antigen-specific TH cells and to clarify the involvement of a TH2/TH1 shift in peripheral blood in pollen specific immunotherapy.

METHODS

After short-term (6-hour) antigen stimulation, antigen-specific TH cells in peripheral blood of Japanese children and young adults with Japanese cedar pollinosis undergoing SCIT were analyzed by multicolor flow cytometry for the presence of the activation marker CD154 and intracellular cytokines.

RESULTS

Twenty-eight patients between 5 and 22 years of age were enrolled in the study; 22 had started SCIT after enrolling in the study (SCIT group), and the remaining 6 were planning to start SCIT in the next off-season (control group). The number of Japanese cedar-specific interleukin (IL) 5-, IL-4-, interferon γ-, IL-17A-, IL-10-, and tumor necrosis factor α-producing TH cells without antigen-driven cell proliferation was determined. The seasonal increase in the number of Japanese cedar-specific IL-5- and IL-4-producing TH cells seen in the control group was suppressed in the SCIT group (P < .005 and <.001, respectively).

CONCLUSION

We report a powerful method for the analysis of antigen-specific TH cells in peripheral blood. This method will contribute to our understanding of immune mechanisms of immunotherapy and help us develop more sophisticated allergen specific immunotherapy.

[Case of pollinosis to grass pollens who presented with dyspnea successfully treated by rush immunotherapy]

We present a 15 years old boy who experienced unusual symptoms for pollen allergy, and successfully treated by rush immunotherapy. The patient started to complain erythema and edema on his face and serous rhinorrhea at 10 years old when going out. He entered baseball team at junior high school, and subsequently experienced choking sensation, dyspnea, face edema, and it was sometimes impossible to continue play. He was diagnosed as bronchial asthma at some hospital, and prescribed many anti-asthma medications including inhaled corticosteroid, which did not take effect. His symptoms deteriorated in summer and ameliorated in winter. When he was 15 years old, he was referred to us by a pediatrician for reassessment of his symptoms. Flow-volume curve was normal, and bronchial provocation test (acetylcholine and histamine), and exercise challenge were negative. IgE antibodies specific to grass pollens were highly positive. We made a diagnosis of pollinosis to grass pollens instead of bronchial asthma. Oral antihistamines and intranasal corticosteroid partially improved his symptoms. We started rush-immunotherapy of grass-pollens (oats and bromegrass), Japanese cedar, and ragweed. His symptoms improved dramatically on the next season of grass pollens.

Two-dimensional distribution of Gi2alpha in the plasma membrane: a critical evaluation by immunocytochemistry

Caveolae have been postulated as a center for signal transduction, because many signaling molecules are concentrated in caveolin-rich fractions. We took Gi2alpha as an example and examined whether it is constitutively concentrated in caveolae. First, the behavior of caveolin and Gi2alpha in density-equilibrium ultracentrifugation was reexamined. By collecting fractions efficiently, caveolin and Gi2alpha were found to distribute differently. Secondly, by novel immunocytochemical methods it was found that the labeling density of Gi2alpha was 2.29 times higher in caveolae than in the non-caveolar plasma membrane. The results indicate that the concentration of Gi2alpha in caveolae is lower than deduced from most biochemical studies.