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identified as Phaseolin and Phytoheameagglutinin. Currently, no treatment is available for food
allergy other than avoidance of offending allergen. However, immunotherapy with modified
offending allergen maybe useful as curative approach.
Using bioinformatics, cysteine protease was identified as a major allergen. showing more than
50% identity with kiwifruit (Act d 1, Act c 1), pollen (Amb a 11) and papaya (Car p 1) and
significant identity with mite and legume allergens. Recombinant cysteine protease showed 89%
sera reactivity in ELISA, indicating it to be a major allergen. Inhibition assay showed purified
protease as potent allergen upon self-inhibition. Cross-reactivity was observed maximally with
dust mite followed by peanut, black gram and fungal allergens. Cysteine protease was able to
activate passively sensitized basophils with upregulated expression of CD203c marker.

Four B-cell and T-cell epitopes were predicted using in-silico tools and further analysed for their
secondary structure and other physicochemical properties. B-cell epitopes showed 52-95%
sequence conservation and T-cell showed 4-65% conservation among homologous allergen
sequences. MHC-class II coverage analysis of T-cell peptides showed about 80% coverage in
Indian population. A significant cross-reactivity of B-cell epitopes with known food allergens
shows potential of these epitopes in diagnostics. Further studies will be done with
immunotherapy with T cell epitopes.

ALLERGENIC FORMULATION FROM MUSHROOM Lentinula edodes

In a project aimed at development of selenium and vitamin D2 enriched formulation from a
mushroom, Lentinula edodes (Shiitake), Naveen Arora is involved in in silico allergenicity
assessment of the formulation, assessment and validation of allergenic potential of developed
formulations using in vitro assays followed by in vivo allergenicity assessment in mice.

Shiitake fungi (Lentinus edodes) is the second most commonly produced edible mushroom in the
world. It is commonly consumed by the eastern world. Many fungal species such as Coprinus
comatus, Psilocybe cubensis, and Boletus edulis etc. are allergenic. Studies have reported the
presence of some allergenic proteins in Lentinus edodes. One such study determined three
immunoreactive proteins of molecular weight 15 kDa, 24 kDa and 37 kDa. Immunoblotting with
patient serum showed two allergic bands at size 15 kDa and 24 KDa, which were exclusively
reactive to shiitake extract. The 37 kDa band showed less reactivity for the extract along with
some cross reactivity with the porcini extract. Skin prick test was performed with in-house
mushroom extract and showed positive reaction. Another study described an atopic patient
allergic to Shiitake mushroom showing oesophageal symptoms. A positive skin prick test was
shown with in house made mushroom extract. Both the basophil activation test and the
histamine release test were positive for the shiitake extract. Clinical symptoms and endoscopic
studies suggested the case of eosinophilic esophagitis.

At IGIB, an in silico screening of protein database (UniProt) for L. edodes’ proteins, obtained a
total of 12,608 hits. Out of these, only 287 protein sequences were shortlisted as they possessed
desired molecular weight (i.e. 15±1 kDa and 24±1 kDa; in accordance to prior art). Upon
subjecting to FASTA in Allergen Online database, only 131 proteins gave hits in either full FASTA
or 80 aa sliding window FASTA mode. Out of these, only 9 proteins gave plausible results (i.e. %
identity value above 50% for full FASTA and 35% for 80 aa sliding window FASTA). Two proteins

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