I. Brusca ignbr@libero.it 1 S. Graci 2 M. Barrale 1 G. Cammilleri 2 M. Zarcone 3 R. Onida 1 A. Costa 2 V. Ferrantelli 2 M.D. Buscemi 2 C.G. Uasuf 4 M....
The diagnosis of allergic reactions to Anisakis remains challenging due to the lack of specific allergens available for routine clinical use. However, the latest version of the multiplex macroarray ALEX-2 now allows the detection of specific IgE against Ani s 1, the major species-specific allergen, as well as Ani s 3 (tropomyosin), a highly cross-reactive molecule with homologs in other allergenic sources. This study aimed to evaluate the potential role of ALEX-2 in diagnosing Anisakis sensitization by comparing it with a previously validated diagnostic algorithm. Serum samples from patients with suspected Anisakis sensitization were consecutively collected at an Italian allergy centre. Diagnosis was based on a history of allergic reactions following seafood consumption, along with negative test results for fish allergy. All patients underwent skin prick testing and specific IgE measurement for Anisakis (p4), Ascaris (p1), shrimp (f24), and Dermatophagoides pteronyssinus (d1), as well as tropomyosins from house dust mites (d205) and shrimp (f351). Additionally, the basophil activation test (BAT) using crude Anisakis extract was performed. Patients were also tested using the ALEX-2 allergy macroarray. Correlation analyses and multiple logistic regression models were applied to assess associations between conventional singleplex tests and the severity of clinical manifestations. A total of 33 eligible subjects were recruited, including 20 females (60.6%). Seven (21.2%) were aged 0–29 years, eleven (33.3%) were 30–60 years old, and fifteen (45.5%) were over 60 years old. ALEX-2 showed positivity for Ani s 1 or Ani s 3 in 39.39% (95% CI: 22.90–57.86%) of subjects with confirmed Anisakis sensitization. A significant correlation was observed between Ani s 3 (r = 0.31 [95% CI: 0.04–0.56], p = 0.01) and Ascaris (r = 0.35 [95% CI: 0.129–0.55], p = 0.004) levels and the severity of clinical reactions. Despite the limitations of this cross-sectional study, including a small sample size, our preliminary findings suggest that the ALEX-2 macroarray may not be sufficiently sensitive for the first-line diagnosis of Anisakis allergy. However, it could provide valuable additional information, as Ani s 1 positivity indicates primary sensitization to the nematode, while Ani s 3 positivity appears to correlate with clinical severity. Larger prospective longitudinal studies are needed to confirm these findings and further assess the predictive value of ALEX-2 in diagnosing Anisakis allergy.
Allergic respiratory diseases such as asthma might be considered multifactorial diseases, having a complex pathogenesis that involves environmental factors and the activation of a large set of immune response pathways and mechanisms. In addition, variations in genetic background seem to play a central role. The method developed for the analysis of the complexities, as association rule mining, nowadays may be applied to different research areas including genetic and biological complexities such as atopic airway diseases to identify complex genetic or biological markers and enlighten new diagnostic and therapeutic targets. A total of 308 allergic patients and 205 controls were typed for 13 single nucleotide polymorphisms (SNPs) of cytokine and receptors genes involved in type 1 and type 2 inflammatory response (IL-4 rs2243250 C/T, IL-4R rs1801275A/G, IL-6 rs1800795 G/C, IL-10 rs1800872 A/C and rs1800896 A/G, IL-10RB rs2834167A/G, IL-13 rs1800925 C/T, IL-18 rs187238G/C, IFNγ rs 24030561A/T and IFNγR2 rs2834213G/A), the rs2228137C/T of CD23 receptor gene and rs577912C/T and rs564481C/T of Klotho genes, using KASPar SNP genotyping method. Clinical and laboratory data of patients were analyzed by formal statistic tools and by a data-mining technique—market basket analysis—selecting a minimum threshold of 90% of rule confidence. Formal statistical analyses show that IL-6 rs1800795GG, IL-10RB rs2834167G positive genotypes, IL-13 rs1800925CC, CD23 rs2228137TT Klotho rs564481TT, might be risk factors for allergy. Applying the association rule methodology, we identify 10 genotype combination patterns associated with susceptibility to allergies. Together these data necessitate being confirmed in further studies, indicating that the heuristic approach might be a straightforward and useful tool to find predictive and diagnostic molecular patterns that might be also considered potential therapeutic targets in allergy.