由家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus, BmNPV)感染导致的家蚕血液型脓病给蚕桑产业造成巨大损失,然而BmNPV与宿主的互作机制至今仍然不明晰。前期的研究发现,BmNPC2可显著促进BmNPV感染,BmNPC2蛋白能够直接与BmNPV...由家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus, BmNPV)感染导致的家蚕血液型脓病给蚕桑产业造成巨大损失,然而BmNPV与宿主的互作机制至今仍然不明晰。前期的研究发现,BmNPC2可显著促进BmNPV感染,BmNPC2蛋白能够直接与BmNPV的囊膜蛋白GP64互作,敲除BmNPC2影响病毒粒子在晚期内体中的膜融合效率。为了鉴定BmNPC2蛋白与病毒囊膜蛋白GP64的互作关键位点,首先通过同源建模以及酵母双杂交试验,筛选出BmNPC2蛋白与囊膜蛋白GP64互作的2个关键区段。随后,将这两个区段位点的氨基酸进行逐个突变,酵母双杂交试验结果表明N95、D97、P105为关键互作位点。在敲除BmNPC2基因的BmE细胞中回补突变3个关键位点的BmNPC2蛋白后,细胞中BmNPV的病毒相对载量显著低于回补野生型BmNPC2蛋白组。以上结果表明,BmNPC2的这3个关键位点的突变显著减弱了BmNPV的感染能力,这些结果将为进一步解析BmNPV侵染家蚕的分子机制提供参考。展开更多
【目的】探究家蚕Bombyx mori肠道特异表达的金属羧肽酶基因BmMCP 18的功能及对外源病毒侵染的抵抗机制。【方法】构建敲除BmMCP18的家蚕BmMCP18KO(C18KO),对C18KO和对照组野生型家蚕(C18KOC)的5龄幼虫中肠以及感染家蚕核型多角体病毒(B...【目的】探究家蚕Bombyx mori肠道特异表达的金属羧肽酶基因BmMCP 18的功能及对外源病毒侵染的抵抗机制。【方法】构建敲除BmMCP18的家蚕BmMCP18KO(C18KO),对C18KO和对照组野生型家蚕(C18KOC)的5龄幼虫中肠以及感染家蚕核型多角体病毒(Bombyx mori nuclear polyhedrosis virus,BmNPV)的家蚕BmMCP18KO(C18KOV)和对照野生型(C18KOCV)的5龄幼虫中肠进行转录组测序;分析差异表达基因并进行GO功能注释和KEGG通路富集;利用qRT-PCR验证相关基因表达。【结果】与对照组C18KOC相比,C18KO有75个基因上调表达,303个基因下调表达。与对照组C18KOCV相比,C18KOV有96个基因上调表达,57个基因下调表达。C18KOC vs C18KO比较组差异表达基因显著富集的GO条目为细胞外空间、细胞表面、肽交联和突触靶标识别等。C18KOCV vs C18KOV比较组差异表达基因富集最显著的GO条目为跨膜转运蛋白活性。C18KO 5龄幼虫中肠转录组中免疫通路、碳水化合物和能量代谢通路相关基因的表达比C18KOC的显著下调,包括Toll和Imd通路及MAPK通路相关基因,而泛素介导的蛋白质水解通路相关基因表达比C18KOC的显著上调。C18KOV 5龄幼虫中肠转录组中的能量代谢基因的表达比C18KOCV的显著上调。qRT-PCR验证结果表明转录组数据可靠。【结论】BmMCP18的功能涉及家蚕中肠的细胞识别、免疫调节和能量代谢,可能是通过参与中肠细胞免疫反应、能量和物质供应,从而影响蚕体对外源病原侵染的抵抗能力。展开更多
Objective:Drug-loaded mucoadhesive silk fibroin(SF)microneedle patch can overcome the limitations of low bioavailability and significant pain associated with traditional treatment methods,such as topical application o...Objective:Drug-loaded mucoadhesive silk fibroin(SF)microneedle patch can overcome the limitations of low bioavailability and significant pain associated with traditional treatment methods,such as topical application or injection of triamcinolone for oral submucous fibrosis(OSF).However,these systems release the drug too quickly,failing to meet the clinical requirements.This study aims to construct a mucoadhesive SF microneedle patch pre-assembled with silk fibroin nanospheres(SFN)and explore its ability to sustain the release of triamcinolone in the treatment of OSF.Methods:SFN was pre-assembled via precipitation reaction and characterized by scanning electron microscope(SEM)for the morphology.The particle size andζ-potential were measured by dynamic light scattering(DLS).Triamcinolone was loaded onto SFN using a diffusional post-loading method.The effective loading of triamcinolone was confirmed using Fourier-transform infrared spectroscopy(FTIR).The concentration of unloaded triamcinolone was quantified by high-performance liquid chromatography.Drug encapsulation efficiency and loading capacity of SFN were then calculated to determine the optimal amount of drug loading.The SFN suspension was pre-mixed with SF solution to prepare the microneedle under-layer.The microneedle morphology was observed by SEM.Compression mechanical tests were performed to evaluate the fracture force of microneedles at different nanosphere contents(5%,10%,and 20%),determining the optimal pre-mixing ratio.Ex-vivo mouse oral mucosa permeation studies were performed to ascertain the insertion depth of the microneedles via histological sections.The adhesive top layer was synthesized using SF and tannic acid,with FTIR confirming its successful synthesis.Its viscoelasticity was characterized by a rheometer,and differential scanning calorimetry analyzed thermal properties.Tensile tests evaluated the interfacial bonding strength between the adhesive layer and microneedle base to ensure no detachment during use.Adhesion to wet oral mucosal tissues was tested and compared to commercial oral patches.Under the optimized conditions,the double-layered mucoadhesive microneedle patch with pre-assembled nanospheres was prepared.Its cell compatibility was evaluated by cell counting kit-8(CCK-8),live/dead staining,and phalloidin staining after co culturing with fibroblasts.The drug release experiment was conducted to demonstrate its sustained release efficacy.Results:SFN(mean diameter 46.25 nm)was successfully prepared.The maximum drug encapsulation efficiency was(63.88±1.09)%(corresponding loading capacity of SFN was(27.41±3.06)%when the weight ratio of triamcinolone/SFN was 0.5.The corporation of SFN did not affect microneedle morphology.The mechanical properties of microneedles decreased with increasing nanosphere amount.Only the fracture force of the group with 5%SFN[(0.07±0.01)N/needle]exceeded the minimum force required for mucosal penetration,thus selected as the optimal pre-mixing ratio.Histological sections confirmed that the SFN microneedles could penetrate the epithelial layer and deliver drugs to OSF affected areas.Adhesion strength between the microneedle base and top layer was(94.8±6.89)kPa,confirming strong bonding with no detachment during use.The wet adhesive strength of the double-layered mucoadhesive microneedle patch[(41.28±7.43)kPa]was significantly enhanced compared to commercial oral patches(4.5 kPa,P<0.01).CCK-8 and live/dead staining results confirmed no significant cytotoxicity.Drug release experiment showed the double-layered mucoadhesive microneedle patch with pre-assembled SFN enabled sustained release time of triamcinolone from 4 days to 14 days.Conclusion:Pre-assembling nanospheres in mucoadhesive SF microneedle patches can extend triamcinolone release time,meeting clinical requirements for sustained drug delivery.展开更多
文摘由家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus, BmNPV)感染导致的家蚕血液型脓病给蚕桑产业造成巨大损失,然而BmNPV与宿主的互作机制至今仍然不明晰。前期的研究发现,BmNPC2可显著促进BmNPV感染,BmNPC2蛋白能够直接与BmNPV的囊膜蛋白GP64互作,敲除BmNPC2影响病毒粒子在晚期内体中的膜融合效率。为了鉴定BmNPC2蛋白与病毒囊膜蛋白GP64的互作关键位点,首先通过同源建模以及酵母双杂交试验,筛选出BmNPC2蛋白与囊膜蛋白GP64互作的2个关键区段。随后,将这两个区段位点的氨基酸进行逐个突变,酵母双杂交试验结果表明N95、D97、P105为关键互作位点。在敲除BmNPC2基因的BmE细胞中回补突变3个关键位点的BmNPC2蛋白后,细胞中BmNPV的病毒相对载量显著低于回补野生型BmNPC2蛋白组。以上结果表明,BmNPC2的这3个关键位点的突变显著减弱了BmNPV的感染能力,这些结果将为进一步解析BmNPV侵染家蚕的分子机制提供参考。
文摘【目的】探究家蚕Bombyx mori肠道特异表达的金属羧肽酶基因BmMCP 18的功能及对外源病毒侵染的抵抗机制。【方法】构建敲除BmMCP18的家蚕BmMCP18KO(C18KO),对C18KO和对照组野生型家蚕(C18KOC)的5龄幼虫中肠以及感染家蚕核型多角体病毒(Bombyx mori nuclear polyhedrosis virus,BmNPV)的家蚕BmMCP18KO(C18KOV)和对照野生型(C18KOCV)的5龄幼虫中肠进行转录组测序;分析差异表达基因并进行GO功能注释和KEGG通路富集;利用qRT-PCR验证相关基因表达。【结果】与对照组C18KOC相比,C18KO有75个基因上调表达,303个基因下调表达。与对照组C18KOCV相比,C18KOV有96个基因上调表达,57个基因下调表达。C18KOC vs C18KO比较组差异表达基因显著富集的GO条目为细胞外空间、细胞表面、肽交联和突触靶标识别等。C18KOCV vs C18KOV比较组差异表达基因富集最显著的GO条目为跨膜转运蛋白活性。C18KO 5龄幼虫中肠转录组中免疫通路、碳水化合物和能量代谢通路相关基因的表达比C18KOC的显著下调,包括Toll和Imd通路及MAPK通路相关基因,而泛素介导的蛋白质水解通路相关基因表达比C18KOC的显著上调。C18KOV 5龄幼虫中肠转录组中的能量代谢基因的表达比C18KOCV的显著上调。qRT-PCR验证结果表明转录组数据可靠。【结论】BmMCP18的功能涉及家蚕中肠的细胞识别、免疫调节和能量代谢,可能是通过参与中肠细胞免疫反应、能量和物质供应,从而影响蚕体对外源病原侵染的抵抗能力。
基金supported by the National Key Research and Development Program(2022YFC2402900)the Key Research and Development Program of Hainan Province(ZDYF2024SHFZ128)the Science and Technology Innovation Program of Hunan Province(2022RC1213),China.
文摘Objective:Drug-loaded mucoadhesive silk fibroin(SF)microneedle patch can overcome the limitations of low bioavailability and significant pain associated with traditional treatment methods,such as topical application or injection of triamcinolone for oral submucous fibrosis(OSF).However,these systems release the drug too quickly,failing to meet the clinical requirements.This study aims to construct a mucoadhesive SF microneedle patch pre-assembled with silk fibroin nanospheres(SFN)and explore its ability to sustain the release of triamcinolone in the treatment of OSF.Methods:SFN was pre-assembled via precipitation reaction and characterized by scanning electron microscope(SEM)for the morphology.The particle size andζ-potential were measured by dynamic light scattering(DLS).Triamcinolone was loaded onto SFN using a diffusional post-loading method.The effective loading of triamcinolone was confirmed using Fourier-transform infrared spectroscopy(FTIR).The concentration of unloaded triamcinolone was quantified by high-performance liquid chromatography.Drug encapsulation efficiency and loading capacity of SFN were then calculated to determine the optimal amount of drug loading.The SFN suspension was pre-mixed with SF solution to prepare the microneedle under-layer.The microneedle morphology was observed by SEM.Compression mechanical tests were performed to evaluate the fracture force of microneedles at different nanosphere contents(5%,10%,and 20%),determining the optimal pre-mixing ratio.Ex-vivo mouse oral mucosa permeation studies were performed to ascertain the insertion depth of the microneedles via histological sections.The adhesive top layer was synthesized using SF and tannic acid,with FTIR confirming its successful synthesis.Its viscoelasticity was characterized by a rheometer,and differential scanning calorimetry analyzed thermal properties.Tensile tests evaluated the interfacial bonding strength between the adhesive layer and microneedle base to ensure no detachment during use.Adhesion to wet oral mucosal tissues was tested and compared to commercial oral patches.Under the optimized conditions,the double-layered mucoadhesive microneedle patch with pre-assembled nanospheres was prepared.Its cell compatibility was evaluated by cell counting kit-8(CCK-8),live/dead staining,and phalloidin staining after co culturing with fibroblasts.The drug release experiment was conducted to demonstrate its sustained release efficacy.Results:SFN(mean diameter 46.25 nm)was successfully prepared.The maximum drug encapsulation efficiency was(63.88±1.09)%(corresponding loading capacity of SFN was(27.41±3.06)%when the weight ratio of triamcinolone/SFN was 0.5.The corporation of SFN did not affect microneedle morphology.The mechanical properties of microneedles decreased with increasing nanosphere amount.Only the fracture force of the group with 5%SFN[(0.07±0.01)N/needle]exceeded the minimum force required for mucosal penetration,thus selected as the optimal pre-mixing ratio.Histological sections confirmed that the SFN microneedles could penetrate the epithelial layer and deliver drugs to OSF affected areas.Adhesion strength between the microneedle base and top layer was(94.8±6.89)kPa,confirming strong bonding with no detachment during use.The wet adhesive strength of the double-layered mucoadhesive microneedle patch[(41.28±7.43)kPa]was significantly enhanced compared to commercial oral patches(4.5 kPa,P<0.01).CCK-8 and live/dead staining results confirmed no significant cytotoxicity.Drug release experiment showed the double-layered mucoadhesive microneedle patch with pre-assembled SFN enabled sustained release time of triamcinolone from 4 days to 14 days.Conclusion:Pre-assembling nanospheres in mucoadhesive SF microneedle patches can extend triamcinolone release time,meeting clinical requirements for sustained drug delivery.