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UDP-glucuronosyltransferase 1A1 (UGT1A1) is an enzyme that is found in the endoplasmic reticulum membrane and can reportedly have a large number of amino acid substitutions that result in the reduction of glucuronidation capacity. For example, adverse drug reactions when patients receive CPT-11 (irinotecan) such as in cancer chemotherapy are caused by amino acid substitutions in UGT1A1. We previously found that the extent of the docking when the hydroxyl residue of bilirubin was oriented toward UDP-glucuronic acid correlated with in vitro conjugation capacity. In this study, we analyzed the conformation of mutant UGT1A1s by means of structural optimization with water and lipid bilayers instead of the optimization in vacuo that we used in our previous study. We then derived a mathematical model that can predict the conjugation capacities of mutant UGT1A1s by using results of substrate docking in silico and results of in vitro analysis of glucuronidation of acetaminophen and 17β-estradiol by UGT1A1s. This experimental procedure showed that the in silico conjugation capacities of other mutant UGT1A1s with bilirubin or SN-38 were similar to reported in vitro conjugation capacities. Our results suggest that this experimental procedure described herein can correctly predict the conjugation capacities of mutant UGT1A1s and any substrate.

Interleukin-13 (IL-13) is associated with allergic airway inflammation and airway remodeling. Our group found a variant with a single nucleotide polymorphism in the IL13 gene at position +2044G>A (rs20541) that was expected to result in the non-conservative replacement of a positively charged arginine (R) with a neutral glutamine (Q) at position 144. IL-13Q144 was associated with augmented allergic airway inflammation and bronchial asthma remodeling. There is some indication that anti-IL-13 monoclonal antibodies can demonstrate a positive effect on the clinical course of refractory asthmatic patients. To date, the binding stability of these agents for IL-13Q144 is unknown. The objective of this study was to investigate the prediction efficacy of the anti-IL-13 monoclonal antibodies tralokinumab and lebrikizumab in asthmatic patients with IL-13R144 and IL-13Q144. The three-dimensional (3-D) structure of tralokinumab was obtained from the Protein Data Bank (PDB ID: 5L6Y), and the complete 3-D structure of lebrikizumab was built through homology modeling. For the binding stability analysis, we performed and analyzed docking simulations of IL-13 with tralokinumab or lebrikizumab. The tralokinumab and lebrikizumab structures changed after binding to IL-13 to facilitate binding with IL-13Q144. The stability analysis with tralokinumab and lebrikizumab demonstrated that IL-13Q144 was more stable than IL-13R144 for both the Rosetta energy score and for the free energy of binding. IL-13Q144 might be a promising predictor of responsiveness to tralokinumab and lebrikizumab treatment for bronchial asthma.

Heat shock proteins (Hsp) are a family of stress-inducible molecular chaperones that play multiple roles in a wide variety of animals. However, the roles of Hsps in parasitic nematodes remain largely unknown. To elucidate the roles of Hsps in the survival and longevity of nematodes, particularly at the 2 most critical stages in their lifecycle, the infective-L3 stage and adult stage, which is subjected to host-derived immunological pressure, we examined the temporal gene transcription patterns of Hsp12.6, Hsp20, Hsp70, and Hsp90 throughout the developmental course of the nematode Nippostrongylus brasiliensis by reverse transcriptase real-time PCR. Nb-Hsp70 and Nb-Hsp90 expression were observed throughout the nematode's lifecycle, while the expression of Nb-Hsp20 was restricted to adults. Interestingly, Nb-Hsp12.6 showed a biphasic temporal expression pattern; i.e., it was expressed in infective-L3 larvae and in adults during worm expulsion from immunocompetent rats. However, the activation of Nb-Hsp12.6 in adult worms was aborted when they infected permissive athymic-rnu/rnu rats and was only marginal when they infected mast-cell-deficient Ws/Ws rats, which exhibited a low response of rat mast cell protease (RMCP) II and resistin-like molecule (Relm)-β expression compared to those observed in immunocompetent rats. Moreover, the activation of Nb-Hsp12.6 was reversed when adult worms were transplanted into the naive rat intestine. These features of Nb-Hsp12.6, the expression of which is not only stage-specific in infective-L3, but is also inducible by mucosal immunity in adults, have implications for the survival strategies of parasitic nematodes in deleterious environmental conditions both outside and inside the host.