چکیده (انگلیسی):

Background: We previously identified MGL_1304 secreted by Malassezia globosa as a sweat antigen for
patients with atopic dermatitis (AD) and cholinergic urticaria (ChU). However, purifying native
MGL_1304 from human sweat or culture supernatant of M. globosa (sup-MGL_1304) is costly and timeconsuming.
Moreover, recombinant MGL_1304 expressed by using Escherichia coli (TF-rMGL_1304) needs
a large chaperon protein and lacks the original glycosylation of yeasts. Thus, we generated a recombinant
MGL_1304 by Pichia pastoris (P-rMGL_1304) and investigated its characteristic features.
Methods: Recombinant MGL_1304 proteins expressed by E. coli and P. pastoris were generated. Properties
of these recombinants and native antigens were compared by western blot analysis, histamine release
tests (HRT) of patients with AD and ChU, and b-hexosaminidase release tests with RBL-48 cells. PrMGL_
1304-specific IgE in sera of patients with AD were measured by sandwich ELISA.
Results: Western blot analysis revealed that IgE of patients with AD bound to all MGL_1304 recombinants
and native antigens. The histamine releasing ability of P-rMGL_1304 was 100 times higher than
that of TF-rMGL_1304, and was comparable to that of sup-MGL_1304. Degranulation rates of RBL-48
cells, sensitized with sera of patients with AD in response to the stimulation of P-rMGL_1304, were
comparable to those of sup-MGL_1304, whereas those of TF-rMGL_1304 were relatively weak. The levels
of P-rMGL_1304-specific IgE in sera of patients with AD were correlated with their disease severities.
Conclusions: P-rMGL_1304 has an antigenicity comparable to the native antigen, and is more useful than
TF-rMGL_1304, especially in HRT and degranulation assay of RBL-48 cells.