Cockroach Allergy Research Articles

From exposure to control: the application of allergen component-resolved diagnosis in the clinical management of cockroach allergies

Cockroaches are one of the most common indoor allergens worldwide, and exposure to cockroach allergens (such as the insect body, debris, and secretions) can trigger severe allergic rhinitis and(or) asthma. Currently, the World Health Organization (WHO)/International Union of Immunological Societies (IUIS) has identified 32 allergenic components in cockroaches, but none of these allergens have shown a clear immunodominance. The sensitization rate to cockroach allergens shows significant variability across different regions and populations and exhibits cross-reactivity with various invertebrates, increasing the complexity of clinical diagnosis and treatment. This article delves into the "Molecular Allergology User's Guide 2.0"(MAUG 2.0) published by the European Academy of Allergy and Clinical Immunology (EAACI) and the research progress on cockroach allergies both domestically and internationally. It elucidates the crucial role of allergen component diagnostic technology in enhancing the diagnosis and treatment of cockroach-induced allergic diseases, efficiently assisting clinicians in identifying common sensitizations and cross-reactivities, thereby offering patients more accurate diagnoses and personalized treatment plans.

Impact of the COVID-19 Pandemic on Cockroach Allergy: A 4-Year Retrospective Study

Introduction: Sensitivity to indoor allergens increases the risks of asthma and the emergence of allergic diseases. Indoor allergens include house dust mite (HDM), pet dander, cockroach (CR), and molds. We investigated how CR sensitivity was affected during the pandemic period. Methods: This study included patients aged ≥18 years who visited the allergy unit of our clinic between March 2018 and March 2022 and who underwent skin prick tests (SPTs) for aeroallergens. Patients were divided into two groups: those of the prepandemic and pandemic periods, depending on the visit dates. Results: In all, 7,687 patients were recruited; 5,074 individuals with negative SPT results were excluded. Among the 2,613 atopic patients, CR sensitivity was detected in 278 (10.6%). The prevalence of CR sensitivity was significantly higher in the pandemic group than in the prepandemic group (12% vs. 8.6%; p < 0.05). The frequency of asthma was higher in patients with CR sensitivity than in others (33.1% vs. 26%, p = 0.011). In addition, individuals with CR sensitivity were older than others (p = 0.001). CR sensitivity was more common in males than in females (44.2% vs. 37.7%, p = 0.034). Moreover, dog and HDM sensitivities were more common in individuals with CR sensitivity than in others (p = 0.004, p < 0.001, respectively). Conclusion: This study reveals an increased sensitivity to CR during the pandemic and establishes an association between such sensitivity and the frequency of asthma. Variability in terms of CR sensitivity across different countries is emphasized. In addition, HDM and dog sensitivities were more common in individuals with CR sensitivity.

A pediatric randomized, controlled trial of German cockroach subcutaneous immunotherapy

Cockroach allergy contributes to morbidity among urban children with asthma. Few trials address the effect of subcutaneous immunotherapy (SCIT) with cockroach allergen among these at-risk children. We sought to determine whether nasal allergen challenge (NAC) responses to cockroach allergen would improve following 1 year of SCIT. Urban children with asthma, who were cockroach-sensitized and reactive on NAC, participated in a year-long randomized double-blind placebo-controlled SCIT trial using German cockroach extract. The primary endpoint was the change in mean Total Nasal Symptom Score (TNSS) during NAC after 12 months of SCIT. Changes in nasal transcriptomic responses during NAC, skin prick test wheal size, serum allergen-specific antibody production, and T-cell responses to cockroach allergen were assessed. Changes in mean NAC TNSS did not differ between SCIT-assigned (n= 28) versus placebo-assigned (n= 29) participants (P= .63). Nasal transcriptomic responses correlated with TNSS, but a treatment effect was not observed. Cockroach serum-specific IgE decreased to a similar extent in both groups, while decreased cockroach skin prick test wheal size was greater among SCIT participants (P= .04). A200-fold increase in cockroach serum-specific IgG4 was observed among subjects receiving SCIT (P< .001) but was unchanged in the placebo group. T-cell IL-4 responses following cockroach allergen stimulation decreased to a greater extent among SCIT versus placebo (P= .002), while no effect was observed for IL-10 or IFN-γ. A year of SCIT failed to alter NAC TNSS and nasal transcriptome responses to cockroach allergen challenge despite systemic effects on allergen-specific skin tests, induction of serum-specific IgG4 serum production and down-modulation of allergen-stimulated T-cell responses.

Frequency and pattern of skin- prick aero-allergic sensitization among children with asthma in Lagos, Nigeria

Abstract: Background: Among children with asthma, aero-allergen sensitisation (AS) results in poorer outcomes, necessitating allergen control. However, the spectrum of AS in childhood asthma in Nigeria is not well-known. We describe the prevalence and pattern of skin- prick AS among children with asthma seen at the paediatric al[1]lergy clinic of the Lagos State Uni[1]versity Teaching Hospital, Ikeja, Lagos, Nigeria. Methods/Material: Retrospective review of routinely-collected data of asthmatic children who had skin -prick test (SPT) at the Paediatric Allergy clinic, conducted with a 9- allergen-extracts kit comprising house-dust mite (HDM) [subtypes: Dermatophagoides pteronysinnus (Der p), Dermatophagoides farina (Der f ), Blomia tropicalis (Blo t)]; Cockroach, Aspergillus fumigatus, cat, dog, Alternaria alternata and grass-mix. AS was defined as wheal diameter ≥ 3 mm above sa[1]line control (0 mm), with hista[1]mine wheal ≥ 3 mm (after 15- minute observation), to at least one antigen. CC –BY 4.0 Results: Between January 2019 and May 2021, fifty-eight children (60.3% boys) aged 2-17 years [median (range; IQR)= 7.0 (2.0, 17.0; 5.0)] had SPT. AS was pre[1]sent in 86.2% (n=50/58), compris[1]ing allergy to: HDM [82.1% (n=46/56) (Der f-67.9%; Blo t: 64.3%; Der p : 51.8%]; cockroach ( 3 9 . 3 % , 2 2 / 5 6 ) ; m o u l d s (Aspergillus- 3.6%, 2/56; Alter[1]naria-1.8%, 1/55) and pet (cat- 1.8%, 1/56; dog-1.8%, 1/56). About two-thirds (65.5%, 38/58) were polysensitised but there was no cross-sensitisation between HDM and cockroach allergy [kappa (95% CI)= -0.004(-0.18, 0.17)]. Conclusions: AS, especially to HDM and cockroach, was common among asthmatic children; a previously-unreported high prevalence of Blomia tropicalis allergy was notable. HDM and cockroach control may be important in our patients.

Extraction, Purification, and Development of Sublingual Film (SLIT Films) Comprising Cockroach Allergen for Treatment of Allergy.

Allergy associated with cockroaches are mostly from the American cockroach (Periplaneta americana) and German cockroach (Blattella germanica). The effective and safe treatment for cockroach allergy is Sublingual immunotherapy (SLIT). In this study, SLIT Films containing purified allergen extract of Periplaneta americana were prepared by solvent casting and were evaluated for their efficiency in delivery. Cockroach allergen extract was prepared and purified by ultrafiltration and chromatography. The molecular weight of protein content was identified and estimated by SDS- PAGE and ELISA. SLIT films were developed by the Quality by Design (QbD) approach and were evaluated for allergen- excipient compatibility, swelling index, taste, diffusion, in vitro dissolution, local toxicity, and stability analysis. Cockroach allergen protein extracts (cut-off 25-71KDa) were identified by SDS-PAGE and quantified by indirect ELISA and further selected for sublingual film preparation. The indirect ELISA results show a higher optical density (OD) value compared to crude extract. The weight uniformity and thickness of the film were between 13-18 mg and 0.04-0.06 mm. The disintegration time was found to be less than 1 min. The cumulative percentage release was also found to be satisfactory. The local toxicity study indicated no signs of irritation in the buccal mucosa of rabbits. The optimised F3 film had uniform thickness, faster disintegration and drug content within pharmacopeial limits. Ex vivo study revealed better permeability with 90% release of allergen in 7 minutes. The formulation was also stable at room temperature during the study period. SLIT Film containing cockroach allergen from Periplaneta americana was successfully developed and evaluated. SLIT films of cockroach allergen could be more beneficial and convenient for emergency use in patients when compared to subcutaneous immunotherapy. SLIT films provide dose accuracy and are a promising alternative for SCIT and SLIT drops and tablets.

Cockroach allergy: Understanding complex immune responses to develop novel therapies.

Cockroach allergy is associated with the development of asthma. The identification of cockroach allergens, which began in the 1990s, is an ongoing process that has led to the current listing of 20 official allergen groups in the WHO/IUIS Allergen Nomenclature database. The function and structure of some of these allergens has been determined and define their natural delivery into the environment and their allergenicity. Analysis of antigenic determinants by X-ray crystallography and rational design of site-directed mutagenesis led to the identification of IgE binding sites for the design of molecules with reduced IgE reactivity and T cell modulatory capacity. New developments in recent years include component analyses of B and T cell reactivity and a recent cockroach immunotherapy trial, CRITICAL, that will contribute to understand the immune response to cockroach and to define future directions for cockroach allergy diagnosis and immunotherapy.

Cockroach Allergy: Is It Common in Jeddah City? A retrospective study

Background: Cockroaches are a common indoor cause of allergic diseases. However, cockroaches are underestimated as a trigger. Objective: To find which allergic diseases are associated with cockroach sensitization in Jeddah city. Methods: This is a retrospective paper completed in 2021. The sample group of this paper involved 192 allergic patients with high levels of specific allergy testing (sIgE) to cockroaches. The data for this paper is from a private centre specialising in allergies in Jeddah, Saudi Arabia. The in vitro tests used were indirect immunoassay tests for the most common indoor allergens. Clinical diagnosis of allergic diseases were also collected. Results were collected via special sheets and tables were extracted. Results: The sample group for this paper was 192 allergic patients. Patients of middle ages are the most likely to experience sensitisation to cockroaches as follow: 56 between 30-40 years (29.1%) and 36 between 40-50 years (18.8%). The commonest indoor allergens associated with cockroach sensitisation are mites, cats and mould: dermatophagoides pteronyssinus as 109 (56.8%), dermatophagoides farinae as 114 (59.4%), cat as 89 (46.4%) and alternaria as 86 (44.8%). The commonest allergic diseases associated with cockroach sensitisation are allergic rhinosinusitis as 74 (38%), atopic dermatitis as 52 (27%) and asthma as 42 (21.8%). Cockroach sensitisation is mostly of mild severity (under class 2); however, this must be linked to clinical allergic symptoms. Conclusion: Cockroach sensitisation is most common in the middle aged population(30-50 years). Cockroach sensitisation is commonly associated with other indoor allergens sensitisation (respectively: mites, cats, and alternaria). The commonest allergic diseases associated with cockroach sensitisation are allergic rhinosinusitis, atopic dermatitis, and asthma. Cockroach sensitisation is of mild severity in most of cases (under class 2); however, this must be correlated to a clinical allergic diagnosis. Keywords: allergic diseases, asthma, allergic rhinitis, atopic dermatitis, atopy, cockroach sensitization, cockroach allergy

Sensitization characteristics of cockroach in Beijing area

Objective:To investigate the sensitization characteristics of cockroach in patients with allergic rhinitis（AR） and/or allergic asthma in Beijing area, and to provide basis for the prevention and treatment of cockroach sensitized population. Methods:Clinical data of patients with allergic rhinitis and/or asthma from January 2017 to December 2019 treated in the outpatient Department of Allergy of Beijing Shijitan Hospital were retrospectively analyzed.Skin prick test （SPT） was performed with cockroach allergen reagents. The cockroach sensitization of patients with different ages and diseases was compared, and the population distribution characteristics of cockroach sensitization were observed.Statistical analysis was performed using SAS 9.4 software. Results:A total of 9915 patients were enrolled in the end.The total positive rate of cockroach SPT was 24.79%（2458/9915）,with the highest positive rate （31.65%） in 15-19 years old group. The positive rate of SPT increased with age in patients less than 14 years old, while the positive rate of SPT was basically flat with age in patients more than 20 years old .The positive rate of cockroach SPT was 24.83% （2355/9484） in allergic rhinitis patients,26.38% （410/1554） in allergic asthma patients, and 27.34% （307/1123） in allergic rhinitis combined with asthma patients. Single cockroach SPT positive accounted for 9.64% （237/2458）, cockroach with other indoor inhalation allergens SPT positive accounted for 90.36% （2221/2458）. The positive SPT rates for combined Der f , Der p,house dust, cat dander, and dog dander were 74.25% （1825/2458）, 66.27% （1629/2458）, 58.99% （1450/2458）, 43.08% （1059/2458）, and 40.85% （1004/2458）, respectively.In allergic rhinitis，asthma，and allergic rhinitis combined with asthma，the cockroach SPT positive rate was higher in the adult group than that in juvenile group，and the difference of positive rate in allergic rhinitis group was statistically significant（25.81% vs 19.07%, P<0.001）.In the juvenile group, the positive rate of SPT in AR combined with asthma was higher than that in AR and that in asthma. Conclusion:Cockroach allergy in patients with AR and/or allergic asthma in Beijing is relatively high, most of them are sensitized by multiple inhalation allergens, and the sensitization degree of adults is higher than that of juvenile.

Cockroach allergy in respiratory allergic patients

Cockroach allergy in respiratory allergic patients

Per a 5-derived T-cell peptides modulate NF-kB signalling to ameliorate allergic inflammation systemically in murine model of cockroach allergic hyper-reactivity.

Peptide immunotherapy (PIT) represents a safe and efficacious therapeutic regimen with in-consequential side-effects. The present study aims to identify T-cell epitopes of Per a 5 allergen, a delta class GST from Periplaneta americana and investigate effect of peptide treatment in murine model of cockroach allergen-mediated hyper-reactivity. The epitopes (TC-P1, TC-P2, and TC-P3) were identified as promiscuous MHC-II binders by MHC-Pred, ProPred, and IEDB analysis tool. Murine model of cockroach allergic hyper-reactivity was generated in Balb/c mice. A marked reduction in cellular infiltration in lungs (3-fold compared with Non-IT) was observed in T3-IT group as evidenced by total leucocyte count in BALF and histology. Specific IgE levels were reduced 3-fold in T2-IT and T3-IT compared with Non-IT with increase in IgG2a levels. IL-4 and IL-13 were reduced upto 2.5-fold in treatment groups compared with Non-IT group. Splenocytes revealed significant increase in levels of CD4+FoxP3+ T cells in TC-P1 and TC-P2 mice demonstrating a systemic shift towards Tregs. Peptide treatment downregulated NF-kB signalling in lung and enhanced the levels of immune-regulatory molecules α1-antitrypsin and elafin. Our results indicate that TC-P1 and TC-P3 alter Th2 cytokine milieu and antibody isotype ratio to suppress allergic inflammation. PIT modulates local and systemic mechanisms to resolve inflammation and possess potential for treatment in cockroach allergy.

Association of three single nucleotide polymorphisms of interleukin -35 for detection and prediction of women with breast cancer in Erbil city

Association of three single nucleotide polymorphisms of interleukin -35 for detection and prediction of women with breast cancer in Erbil city

Identification of Per a 13 as a novel allergen in American cockroach

BackgroundCockroaches are an important source of indoor allergens. Environmental exposure to cockroach allergens is closely associated with the development of immunoglobulin E (IgE)-mediated allergic diseases. However, the allergenic components in the American cockroaches are not fully studied yet. In order to develop novel diagnostic and therapeutic strategies for cockroach allergy, it is necessary to comprehensively investigate this undescribed allergen in the American cockroach. MethodsThe full-length cDNA of the potential allergen was isolated from the cDNA library of the American cockroach by PCR cloning. Both the recombinant and natural protein molecules were purified and characterized. The allergenicity was further analyzed by enzyme linked immunosorbent assay, immunoblot, and basophil activation test using sera from cockroach allergic patients. ResultsA novel allergen belonging to glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was firstly identified in the American cockroach and named as Per a 13. The cDNA of this allergen is 1255 base pairs in length and contains an open reading frame of 999 base pairs, encoding 332 amino acids. The purified Per a 13 was fully characterized and assessed to react with IgEs from 49.3 % of cockroach allergic patients, and patients with allergic rhinitis were more sensitized to it. Moreover, the allergenicity was further confirmed by immunoblot and basophil activation test. ConclusionsWe firstly identified GAPDH (Per a 13) in the American cockroach, which is a novel type of inhalant allergen derived from animal species. These findings could be useful in developing novel diagnostic and therapeutic strategies for cockroach allergy.

The first reported case of Blaptica dubia cockroach allergy

BackgroundPeriplaneta americana and Blattella germanica cockroaches are widespread, and risk of sensitization increases in urban environments where these roaches thrive as household pests. There are no prior reports of Blaptica dubia cockroach allergy, though human exposure to B. dubia is increasing through commercial breeding as feeder insects.Case presentationA 50-year-old B. dubia cockroach breeder presented with progressively worsening upper and lower respiratory symptoms in recent years. Symptoms were worse with exposure to her B. dubia roach colony. Skin prick testing (SPT) to B. dubia cast skin, internal organs, and feces was performed in both the subject and a human control. Testing for P. americana and B. germanica sensitization was also performed in the subject. SDS–Polyacrylamide gel electrophoresis (PAGE), immunoblots, and enzyme-linked immunosorbent assays (ELISA) studies were performed using the subject and control serums to explore for specific IgE binding to B. dubia as well as P. americana. Our results showed SPT was positive to B. dubia internal organs in the subject and negative in the control. In the subject, SPT was negative to P. americana though intradermal (ID) testing was positive and serum specific IgE (sIgE) testing was negative to B. germanica. Immunoblotting of the subject's serum to B. dubia internal organ extract showed several distinct bands of IgE binding at 47 kilodaltons (kD), 68 kD, 74 kD, 83 kD, and 118 kD. The strongest band was at 118 kD on B. dubia immunoblotting, which was absent in P. americana on SDS-PAGE. ELISA studies showed an increased IgE response to both B. dubia and P. americana in the subject versus the control.ConclusionsThis case confirmed the first reported allergy to B. dubia cockroaches. There may be cross-reactivity between B. dubia and P. americana, though our case suggests SPT and sIgE testing using P. americana and B. germanica extract has potential to miss a B. dubia cockroach allergy. This allergy is likely underreported, and further study is needed to explore the natural history of B. dubia cockroach allergy.

Oral toxicity of various Stemona collinsiae crude extracts against nymph and adult stages of American cockroach, Periplaneta americana (Dictyoptera: Blattodea)

Stemona collinsiae exhibits insecticidal resistance against various pests and insect vectors. However, insecticidal activity of S. collinsiae roots has not been tested for some insect vectors, including the American cockroach, Periplaneta americana. The synanthropic insect P. americana is a reservoir of pathogenic and non-pathogenic microorganisms and a cause of infectious diseases and cockroach allergy. This important vector transmits microorganisms to animals and humans to cause vector-borne diseases. This research involved detection of the nymphicidal and adulticidal activities of S. collinsiae root extracts against P. americana through oral administration. The effects of hexane, dichloromethane, ethanol, and water crude extracts were tested on final instar nymphs and adult P. americana. After P. americana ingested bait containing hexane and dichloromethane crude extracts, signs of toxicity occurred, such as hind leg shaking, whole-body tremor, immobility, abdomen swelling, and death. At 48 h, the nymphs and adult P. americana that ingested dichloromethane crude extract-containing bait showed corrected mortality of 65%–100% and 20%–100%, respectively. Whereas none of the nymphs and adult P. americana that ingested the water crude extract-containing bait died (0% corrected mortality). When we dissected alimentary canals of the dead P. americana that had ingested dichloromethane and hexane crude extract-containing baits, the foreguts were found to be swollen. TLC analysis showed the dichloromethane and hexane crude extracts contained the alkaloid didehydrostemofoline and unknown fluorescent substances. Phytochemicals from crude extracts were detected in extracts of dissected alimentary canals using thin-layer chromatography, and didehydrostemofoline alkaloid and unknown fluorescent substances were found in cockroaches that ingested dichloromethane- and hexane-containing baits. The cause of death of P. americana may be attributed to alkaloids and synergistic effects of other substances in S. collinsiae root extract. Mechanisms of action might include several pathways involved in nervous system function. Thus, dichloromethane and hexane crude extracts can be developed as alternative active ingredients in a natural insecticide for cockroach control.

Component-Resolved Diagnosis of American Cockroach (Periplaneta americana) Allergy in Patients From Different Geographical Areas

Background: Manifestation of respiratory allergy to American cockroach (Periplaneta americana) is prominent in the subtropical and tropical areas. However, co-existing perennial indoor inhalant allergies frequently compromise clinical diagnosis of cockroach allergy, and the analysis of sensitization pattern is limited by the lack of Periplaneta allergens widely available for component-resolved diagnostics (CRD).Objective: To evaluate a collection of previously described recombinant Periplaneta allergens for CRD in cockroach allergy.Methods: A panel of nine recombinant Periplaneta allergens (Per a 1–5, 7–10) was generated, purified, and subjected to physicochemical characterization by applying circular dichroism (CD) spectroscopy, dynamic light scattering (DLS), amino acid (AA) analysis, and mass spectrometry (MS). Patients (n = 117) from India, Korea, Venezuela, and Iran, reporting perennial respiratory indoor allergies with IgE sensitization to cockroach (P. americana and/or Blattella germanica), were included. The sensitization profile was monitored by the experimental ImmunoCAP testing.Results: ImmunoCAP testing confirmed IgE sensitization to Periplaneta and/or Blattella extract in 98 of 117 patients (r = 0.95). Five out of 117 patients were sensitized to only one of the two cockroach species. Within the whole study group, the prevalence of sensitization to individual allergens varied from 4% (Per a 2) to 50% (Per a 9), with the highest IgE values to Per a 9. Patients from four countries displayed different sensitization profiles at which Per a 3 and Per a 9 were identified as major allergens in India and Korea. Periplaneta-derived lipocalin and myosin light chain were characterized as new minor allergens, designated as Per a 4 and Per a 8. Periplaneta extract showed higher diagnostic sensitivity than all individual components combined, suggesting the existence of allergens yet to be discovered.Conclusion: Utilization of a panel of purified Periplaneta allergens revealed highly heterogeneous sensitization patterns and allowed the classification of lipocalin and myosin light chain from Periplaneta as new minor allergens.

A Component-Resolved Therapeutic Vaccine for Cockroach Allergy Made of Per a 9 and Transforming Growth Factor-β Homologue, an Immunosuppressive Protein of Brugia malayi.

Allergen-specific-immunotherapy (ASIT) can cause long-term resolution of allergic diseases, reduces drug use and chances of new allergen sensitization. Nevertheless, therapeutic vaccine and data on ASIT efficacy for cockroach (CR) allergy are relatively scarce. In this study, efficacy and mechanism of a novel intranasal vaccine consisting of liposome (L)-entrapped mixture of American CR (Periplaneta americana) major allergen (Per a 9) and immunosuppressive protein of Brugia malayi nematode named transforming growth factor-beta homologue (TGH) in treatment of CR allergy were investigated along with two other vaccines (L-Per a 9 alone and L-TGH alone). All three vaccines could reduce pathogenic type 2 response and lung immunopathology in the vaccines-treated CR-allergic mice, but by different mechanisms. L-Per a 9 caused a deviation of the pathogenic type 2 to type 1 response (IFN-γ-upregulation), whereas the L-(TGH + Per a 9) and L-TGH generated regulatory immune responses including up-expression of immunosuppressive cytokine genes and increment of serum adenosine and lung indoleamine-2,3-dioxygenase-1 which are signatures of regulatory T cells (Tregs) and tolerogenic dendritic cells, respectively. The L-(TGH + Per a 9) should be further evaluated towards clinical application, as this vaccine has a propensity to induce broadly effective therapeutic effects for inhalant allergies.

Functional characterization of gamma-delta (γδ) T cells in allergy

Abstract Despite a growing consensus on the involvement of γδ T cells in allergy and other human immunological disorders, the detailed mechanisms remain hypothetical due to lack of investigative tools. Herein, we sought to develop functional assays to study the role of γδ T cells in allergy. Using an Activation-Induced Marker (AIM) assay, based on the upregulation of 4-1BB (CD137) and CD69, we were able to detect ex vivo allergen-specific responses from γδ T cells to multiple allergen extracts in human PBMCs, including mouse, cockroach (CR), house dust mite (HDM) and timothy grass (TG) allergens, which were reproducible and observed in multiple allergic cohorts. The magnitude of allergen-reactive γδ T cells differed between allergic and non-allergic cohorts with HDM and TG allergy, but not mouse or CR allergy. Further characterization showed that the γδ T cells reactive to mouse allergen were mostly the Vδ2 subset and from effector memory (Tem and Temra) compartments. Interestingly, in mouse-specific allergic donors we found differential polarized responses for γδ and ab T cells, with a Th1 and Th2 pattern, respectively. Using a complementary AIM assay for CD40L (CD154) combined with intracellular staining (ICS), we observed that Th1 polarization (INFg and TNFa) in responses to mouse extract was also common in non-allergic donors. Conversely, In the case of CR responses, Th1 polarization of Vδ2 T cells was only observed in the allergic cohort. Overall, these results suggest that allergen-specific Vδ2 T cells are potential to skew dysregulated cytokine responses in immunotherapy. In conclusion, we developed new functional assays that serve as tools for in-depth characterization and deciphering the roles of γδ T cells in allergy.

IgE and T Cell Reactivity to a Comprehensive Panel of Cockroach Allergens in Relation to Disease.

IgE sensitization to cockroach allergens is associated with development of allergic diseases, such as asthma. To understand the relevance of different cockroach allergens for diagnosis and immunotherapy, a comprehensive analysis of IgE antibody levels and T cell reactivity to an expanded set of cockroach allergens and their relationship to disease was performed in a cohort of USA cockroach sensitized patients. IgE antibody levels to recombinant chitinase and hemocyanin were measured for 23 subjects by custom-made ImmunoCAPs and compared with IgE levels to eight cockroach allergens we previously reported for the same cohort. Ex vivo T cell activation (Ox40/PDL-1 expression) of PBMCs stimulated with peptide pools derived from 11 German cockroach proteins, including nine official cockroach allergens, plus chitinase and vitellogenin, was determined by flow cytometry. IgE prevalences to chitinase (17%) and hemocyanin (44%) were comparable to values for the other eight allergens that we previously reported (21–57%). Hemocyanin (Bla g 3), was a major allergen (one to which more than 50% of patients with an allergy to its source react) for a sub-group of 15 highly cockroach-sensitized subjects (IgE > 3.5 kUA/L: 53%). Chitinase was officially named as new allergen Bla g 12. Cockroach-specific IgE levels in plasma showed excellent correlation with the sum of 10 allergen-specific IgE (r = 0.94, p < 0.001). T cell reactivity to 11 proteins was highly variable among subjects, the highest being for vitellogenin, followed by Bla g 3. The main finding was that cockroach allergen-specific IgE and T cell reactivity patterns were unique per subject, and lacked immunodominant allergens and correlation with clinical phenotype/disease severity in the studied cohort. Knowing the subject-specific B/T cell reactivity profiles to a comprehensive panel of cockroach allergens will contribute to diagnosis of cockroach allergy and will be important for planning and assessing allergen immunotherapy outcomes, according to the allergen content in therapeutic cockroach extracts.

Cockroach Allergy, Allergen Based Immuno Diagnostic and Specific Immunotherapy: Present Status and Future Trends

Cockroach allergy sensitivity is increasing alarmingly. As in the modern world people choose to stay indoors which increased the inhalation of fine dust emerging from cockroach scales present in air causing the allergy symptoms in sensitive people. The scheme of flats in apartments with long lengthier toilet ducted lines are the sources for cockroach habitat. City apartment buildings are specifically responsible for increased cockroach allergy problem. Cockroach allergen causing allergy has been proclaimed around the world and the most typical cockroaches associated with allergy are the German cockroach Blattella germanica and the American cockroach Periplaneta americana. The secretion and remains of the whole insect are the origin of environmental cockroach allergen. Diagnosis is by specific IgE test followed by Skin Prick Test SPT. Long term management of allergy disorders apart from pharmacotherapy is done by preventive measures and Allergen Specific Immunotherapy ASI in the form of either Subcutaneous Immunotherapy SCIT or by Sublingual Immunotherapy SLIT to reduce the allergy symptoms and enhance Quality of Life as against observed by Pharmacotherapy. In this article present status and future trends on cockroach allergy allergen diagnosis and specific immunotherapy have been reviewed.

IgE and IgG4 responses to shrimp allergen tropomyosin and its epitopes in patients from coastal areas of northern China.

Sensitization to allergens and their peptides varies among patients due to geographical or ethnic differences. The present study aimed to investigate immunoglobulin (Ig)E and IgG4 responses to tropomyosin and its peptides in shrimp allergic patients from northern China. A total of 92 subjects were studied, including 35 shrimp allergic patients, 29 patients with house dust mite (HDM) and/or cockroach allergic patients and 28 healthy volunteers. Serum IgE and IgG4 antibodies to recombinant shrimp tropomyosin (rPen a 1) and its peptides were measured by means of a light-initiated chemiluminescent assay. A total of 9 major sequential epitopes of Pen a 1 reported in the literature were synthesized. Of 35 shrimp allergic patients, 25 (71.4%) had positive Pen 1-specific IgE (sIgE) antibodies and 22 (62.9%) contained measurable rPen a 1-specific IgG4 (sIgG4) antibodies. A strong IgG4 response accompanied the presence of IgE to Pen a 1. None of the patients with HDM and/or cockroach allergy demonstrated IgE reactivity to rPen a 1. The reaction frequency of IgE binding epitope was 20–48%, while that of IgG4 binding epitope was 63.6–3.9%. The IgE and IgG4 recognition patterns of the tropomyosin peptides demonstrated high interpatient heterogeneity. Diversity of IgE binding epitopes was positively correlated with Pen a 1 sIgE levels. In the study population, tropomyosin was a major allergen recognized by the majority of shrimp allergic patients, which is consistent with previous reports. However, none of the 9 epitopes are major (reaction frequency >50%) IgE-binding regions, indicating the epitopes profile may be different in other regions.