ABSTRACT
C-type lectins (CTLs) act as pattern recognition receptors (PRRs) to initiate the innate immune response in insects. A CTL with dual carbohydrate recognition domains (CRDs) (named immulectin-4 [IML-4]) was selected from the Ostrinia furnacalis transcriptome dataset for functional studies. We cloned the full-length complementary DNA of O. furnacalis IML-4 (OfIML-4). It encodes a 328-residue protein with a Glu-Pro-Asn (EPN) and Gln-Pro-Asp (QPD) motifs in 2 CRDs, respectively. OfIML-4 messenger RNA levels increased significantly upon the bacterial and fungal infection. Recombinant OfIML-4 (rIML-4) and its individual CRDs (rCRD1 and rCRD2) exhibited the binding ability to various microorganisms including Escherichia coli, Micrococcus luteus, Pichia pastoris, and Beauveria bassiana, and the cell wall components including lipopolysaccharide from E. coli, peptidoglycan from M. luteus or Bacillus subtilis, and curdlan from Alcaligenes faecalis. The binding further induced the agglutination of E. coli, M. luteus, and B. bassiana in the presence of calcium, the phagocytosis of Staphylococcus aureus by the hemocytes, in vitro encapsulation and melanization of nickel-nitrilotriacetic acid beads, and a significant increase in phenoloxidase activity of plasma. In addition, rIML-4 significantly enhanced the phagocytosis, nodulation, and resistance of O. furnacalis to B. bassiana. Taken together, our results suggest that OfIML-4 potentially works as a PRR to recognize the invading microorganisms, and functions in the innate immune response in O. furnacalis.
ABSTRACT
AIM: To observe the clinical efficacy of the combined use of small incision lenticule extraction (SMILE)-derived lenticule patches in corneal dermoid excision, with fixation of the lenticule patches assisted by fibrin glue. METHODS: Seventeen eyes of 17 patients with corneal dermoid were treated with dermoid removal combined with SMILE-derived lenticule transplantation. All lenticule patches were fixed by fibrin glue. Ocular changes were assessed using slit lamp microscopy and anterior-segmental optical coherence tomography. The best-corrected visual acuity (BCVA) and ocular dioptric variations were examined preoperatively and postoperatively. Intraocular pressure (IOP) was also monitored in all visited time. RESULTS: Totally, 18 lenticule patches were used on 17 eyes of 17 cornea dermoid patients. The mean follow-up time was 11.47±5.28mo. All lenticule patches were successfully glued, kept on its location and maintained transparent during the follow-up time, with a consecutive epithelial cover for 1wk. Nine of the patients could coordinate visual and optometry exam well. Their preoperative BCVA is 0.60±0.35 in decimal, significantly improved to 0.80±0.26 in decimal at 6mo postoperatively (Z=-2.392, P=0.017), but the changes of their corneal astigmatism diopters showed no significance, with 2.22±1.91 D preoperatively, and 2.28±1.31 D at 6mo postoperatively (Z=-0.135, P=0.893). Limbal pannus formation occurred in 4 (23.52%) cases and decreased with the application of tacrolimus eyedrops. IOP increased in 2 (11.76%) cases, but well decreased by timolol maleate eyedrops. All the adult patients or guardians of minor patients were satisfied with the cosmetic improvement. CONCLUSION: Dermoid excision combined with transplantation of SMILE-derived lenticule patches using fibrin glue is a safe and effective novel tectonic keratoplasty procedure for corneal dermoid.
ABSTRACT
The eicosanoid signaling pathway mediates insect immune reactions to a wide range of stimuli. This pathway begins with the biosynthesis of arachidonic acid (AA) from the hydrolysis of phospholipids catalyzed by phospholipase A2 (PLA2 ). We report here that the PLA2 inhibitor, dexamethasone (DEX), impaired the innate immune response including nodulation, encapsulation, and melanization in Ostrinia furnacalis larvae, while AA partially reversed these effects of DEX. We cloned a full-length complementary DNA encoding a PLA2 , designated as OfsPLA2 , from O. furnacalis. The open reading frame of OfsPLA2 encodes a 195-amino acid residue protein with a 22-residue signal peptide. Sequence alignment analyses indicated that O. furnacalis PLA2 might be a Group III secretory PLA2 . The highest transcript levels of OfsPLA2 were detected in the fat body, and its transcript levels increased dramatically after infection with Escherichia coli, Micrococcus luteus, or Beauveria bassiana. Recombinant OfsPLA2 significantly induced prophenoloxidase (PPO) activation in larval hemolymph in the presence of Ca2+ and encapsulation of agarose beads. Injection of recombinant OfsPLA2 into larvae resulted in increased transcript levels of attacin, defencin, and moricin-3 genes. Our results demonstrate the involvement of the eicosanoid signaling pathway in the innate immune response of O. furnacalis larvae and provide new information about the roles of O. furnacalis secretory PLA2 in activating PPO and antimicrobial peptide production.
