Biology subjects

Kolbe, M.

Publications and source records attributed to Kolbe, M..

8 recordsLinked to original sources

bioRxiv2022

Novel Multi-Epitope Vaccine candidate derived from critically important proteins of Monkeypox isolates

BackgroundOn May 7, 2022, a case of monkeypox virus (MPXV) has been reported to the WHO. It causes a viral zoonotic disease with characteristics comparable to that of smallpox cases. Monkeypox could be a serious health concern as it is already spreading to multiple countries worldwide. To prevent the monkeypox infection and for its early detection, a potential vaccine and diagnostic candidate is urgently required. MethodIn present study we have used different in silico methods to screen the entire genome with its approximately 191 genes for potential epitopes present in proliferation and virulent proteins of monkeypox virus. All protein sequences were retrieved from different genomic and proteome databases listed in Uniprot or NCBI. ResultsIn the present study we have screened potential epitopes from 11 different proteins of Monkeypox. All the included protein play an important role in pathogenesis and/or proliferation of Monkeypox virus. We have identified in total 984 CTL and 168 HTL epitopes with highest score in our epitope screening. The reported epitopes could be potential candidates for the design of an early detection diagnostic kit specific for the monkeypox virus. Out of these target peptides we have included a total of 39 CTL epitopes and 39 HTL epitopes in design of multi-epitope vaccine candidates. These shortlisted epitopes are highly conserved amongst different strains and origin of monkeypox viruses. The population coverage by joint administration of CTL and HTL MEVs is predicted to be high with the epitopes showing potential to bind upto 24 different CTL and HTL HLA allele molecules. The epitopes used in MEVs are examined to be highly immunogenic, non allergic but antigenic, and non toxic. All the CTL and HTL MEVs designed utilizing the epitopes have physiochemical properties favor its over expression in human cells. The optimized cDNA constructs of CTL and HTL MEVs also favor over expression of MEVs in human cells. Overall, the MEV construct proposed by us are fissile for expression in the lab and for further in vivo studies. ConclusionControl and fight against emerging diseases such as MPXV requires pathogen diagnostic and novel vaccine approaches. We screened for several epitopes and designed a MEV providing a potential solution for both purposes. Our method allows rapid screening and provides a rational strategy for the development of vaccine candidate effective in fighting MPXV and other unexpected upcoming diseases.

immunology↗

bioRxiv2022

Novel 'GaEl antigenic patches' identified by 'reverse epitomics' approach to design multi-patch vaccines against NIPAH infection, a silent threat to global human health

BackgroundNipah virus (NiV) is a zoonotic virus that causes lethal encephalitis and respiratory disease with the symptom of endothelial cell-cell fusion. Several NiV outbreaks have been reported since 1999 with nearly annual occurrences in Bangladesh. The outbreaks had high mortality rates ranging from 40 to 90%. No specific vaccine has yet been reported against NiV. MethodologyRecently, several vaccine candidates and different designs of vaccines composed of epitopes against NiV were proposed. Most of the vaccines target single protein or protein complex subunits of the pathogen. The Multi-epitope vaccines proposed also cover a largely limited number of epitopes and hence their efficiency is still pending. To address the urgent need for a specific and effective vaccine against NiV infection in the present study, we have utilized the Reverse Epitomics approach ("overlapping-epitope-clusters-to-patches" method) to identify antigenic patches (Ag-Patches) and utilize them as immunogenic composition for Multi-Patch vaccine (MPV) design. The designed MPVs were analyzed for immunologically crucial parameters, physiochemical properties and interaction with Toll-like receptor 3 ectodomain. ResultsIn total 30 CTL (Cytotoxic T lymphocyte) and 27 HTL (Helper T lymphocytes) antigenic patches were identified from the entire NiV proteome based on the clusters of overlapping epitopes. These identified Ag-Patches cover a total of discreet 362 CTL and 414 HTL epitopes from entire proteome of NiV. The antigenic patches were utilized as immunogenic composition for the design of two CTL and two HTL multi-patch vaccines. The 57 antigenic patches utilized here cover 776 overlapping epitopes targeting 52 different HLA class I and II alleles providing a global ethnically distributed human population coverage of 99.71%. Such large number of epitope coverage resulting in large human population coverage cannot be reached with single protein/subunit or multi-epitope based vaccines. The reported antigenic patches also provide potential immunogenic composition for early detection diagnostic kits for NiV infection. Further, all the MPVs & Toll-Like Receptor ectodomain complexes show stable nature of molecular interaction with numerous hydrogen bonds, salt bridges and non-bounded contacts formation and acceptable root mean square deviation and fluctuation. The cDNA analysis show a favorable large scale expression of the MPV constructs in human cell line. ConclusionBy utilizing the novel Reverse epitomics approach highly immunogenic novel GaEl antigenic patches (GaEl Ag-Patches) a synonym term for antigenic patches, were identified and utilized as immunogenic composition to design four MPVs against NiV. We conclude that the novel Multi-Patch Vaccines is a potential candidate to combat NiV, with greater effectiveness, high specificity and large human population coverage worldwide.

immunology↗

bioRxiv2021

Exploring the structural basis to develop efficient multi-epitope vaccines displaying interaction with HLA and TAP and TLR3 molecules to prevent NIPAH infection, a global threat to human health

BackgroundNipah virus (NiV) is an emerging zoonotic virus that caused several serious outbreaks in the South Asian region with high mortality rates ranging from 40 to 90% since 2001. NiV infection causes lethal encephalitis and respiratory disease with the symptom of endothelial cell-cell fusion. No specific vaccine has yet been reported against NiV. Methodology and Principal FindingsRecently, the design of some Multi-Epitope Vaccines (MEV) has been proposed but that involves vary limited number of epitopes which limits the potential of vaccine. To address the urgent need for a specific and effective vaccine against NiV infection, in the present study, we have designed two MEVs composed of 33 Cytotoxic T lymphocyte (CTL) epitopes and 38 Helper T lymphocyte (HTL) epitopes. Both the MEVs carry potential B cell linear epitope overlapping regions, B cell discontinuous epitopes as well as IFN-{gamma} inducing epitopes. Hence the designed MEVs carry potential to elicit cell-mediated as well as humoral immune response. Selected CTL and HTL epitopes were validated for their stable molecular interactions with HLA class I and II alleles as well as in case of CTL epitopes, with human transporter associated with antigen processing (TAP). Human {beta}-defensin 2 and {beta}-defensin 3 were used as adjuvants to enhance the immune response of both the MEVs. Molecular dynamics simulation studies of MEVs-TLR3 ectodomain (Toll-Like Receptor 3) complex indicate the stable molecular interaction. Further, the codon optimized cDNA of both the MEVs has shown high expression potential in the mammalian host cell line (Human). Hence for further studies, the designed MEV constructs could be expressed and tried in-vivo as potential vaccine candidates against NiV. ConclusionWe conclude that the MEVs designed and in silico validated here could be highly potential vaccine candidate to combat NiV, with greater effectiveness, high specificity and large human population coverage worldwide. AUTHOR SUMMARYNipah Virus (NiV) has caused several outbreaks in past two decades calming large number of human lives. Our present work aims to design and in silico validate Multi-Epitope Vaccine against NiV. The current approach to design vaccine involves whole virus or full length proteins as vaccine candidates against NiV. These approaches carry chances of raising the unwanted non-neutralizing antibodies which have been found to cause clinical complexities. Recently few Multi-Epitope vaccines have also been proposed, but they have involved limited number of epitopes for vaccine design in result limiting the effectiveness and human population coverage. Here in our MEVs we have involved all the proteins of NiV to design the vaccine. Moreover since we have used in silico validated epitopes we may conclude that the here proposed MEVs would be highly specific, effective and potential vaccine candidate to combat NiV with large human population coverage worldwide.

immunology↗

bioRxiv2021

Novel method for quantifying AhR-ligand binding affinities using Microscale Thermophoresis

The aryl hydrocarbon receptor (AhR) is a highly conserved cellular sensor of a variety of environmental pollutants and dietary-, cell- and microbiota-derived metabolites with important roles in fundamental biological processes. Deregulation of the AhR pathway is implicated in several diseases, including autoimmune diseases and cancer, rendering AhR a promising target for drug development and host-directed therapy. The pharmacological intervention of AhR processes requires detailed information about the ligand binding properties to allow specific targeting of a particular signalling process without affecting the remaining. Here, we present a novel microscale thermophoresis-based approach to monitoring the binding of purified recombinant human AhR to its natural ligands in a cell-free system. This approach facilitates a precise identification and characterization of unknown AhR ligands and represents a screening strategy for the discovery of potential selective AhR modulators.

biochemistry↗

bioRxiv2020

Computationally validated SARS-CoV-2 CTL and HTL Multi-Patch Vaccines designed by reverse epitomics approach, shows potential to cover large ethnically distributed human population worldwide

BackgroundThe SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) is a positive-sense single-stranded RNA coronavirus responsible for the ongoing 2019-2020 COVID-19 outbreak. The highly contagious COVID-19 disease has spread to 216 countries in less than six months. Though several vaccine candidates are being claimed, an effective vaccine is yet to come. In present study we have designed and theoretically validated novel Multi-Patch Vaccines against SARS-CoV-2. MethodologyA novel reverse epitomics approach, "overlapping-epitope-clusters-to-patches" method is utilized to identify multiple antigenic regions from the SARS-CoV-2 proteome. These antigenic regions are here termed as "Ag-Patch or Ag-Patches", for Antigenic Patch or Patches. The identification of Ag-Patches is based on clusters of overlapping epitopes rising from a particular region of SARS-CoV-2 protein. Further, we have utilized the identified Ag-Patches to design Multi-Patch Vaccines (MPVs), proposing a novel methodology for vaccine design and development. The designed MPVs were analyzed for immunologically crucial parameters, physiochemical properties and cDNA constructs. ResultsWe identified 73 CTL (Cytotoxic T-Lymphocyte), 49 HTL (Helper T-Lymphocyte) novel Ag-Patches from the proteome of SARS-CoV-2. The identified Ag-Patches utilized to design MPVs cover 768 (518 CTL and 250 HTL) overlapping epitopes targeting different HLA alleles. Such large number of epitope coverage is not possible for multi-epitope vaccines. The large number of epitopes covered implies large number of HLA alleles targeted, and hence large ethnically distributed human population coverage. The MPVs:Toll-Like Receptor ectodomain complex shows stable nature with numerous hydrogen bond formation and acceptable root mean square deviation and fluctuation. Further, the cDNA analysis favors high expression of the MPVs constructs in human cell line. ConclusionHighly immunogenic novel Ag-Patches are identified from the entire proteome of SARS CoV-2 by a novel reverse epitomics approach. We conclude that the novel Multi-Patch Vaccines could be a highly potential novel approach to combat SARS-CoV-2, with greater effectiveness, high specificity and large human population coverage worldwide. O_FIG O_LINKSMALLFIG WIDTH=187 HEIGHT=200 SRC="FIGDIR/small/284992v1_ufig1.gif" ALT="Figure 1"> View larger version (84K): org.highwire.dtl.DTLVardef@176f27org.highwire.dtl.DTLVardef@82a4fcorg.highwire.dtl.DTLVardef@11db43forg.highwire.dtl.DTLVardef@12495b2_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOABSTRACT FIGURE:C_FLOATNO A Multi-Patch Vaccine design to combat SARS-CoV-2 and a method to prepare thereof. Multi-Patch Vaccine designing to combat SARS-CoV-2 infection by reverse epitomics approach, "Overlapping-epitope-clusters-to-patches" method. C_FIG

immunology↗

bioRxiv2020

Structural basis to design multi-epitope vaccines against Novel Coronavirus 19 (COVID19) infection, the ongoing pandemic emergency: an in silico approach

The 2019 novel coronavirus (COVID19 / Wuhan coronavirus), officially named as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is a positive-sense single-stranded RNA coronavirus. SARS-CoV-2 causes the contagious COVID19 disease also known as 2019-nCoV acute respiratory disease and has led to the ongoing 2019-20 pandemic COVID19 outbreak. The effective counter measures against SARS-CoV-2 infection require the design and development of specific and effective vaccine candidate. In the present study, we have screened and shortlisted 38 CTL, 33 HTL and 12 B cell epitopes from the eleven Protein sequences of SARS-CoV-2 by utilizing different in silico tools. The screened epitopes were further validated for their binding with their respective HLA allele binders and TAP (Transporter associated with antigen processing) molecule by molecular docking. The shortlisted screened epitopes were further utilized to design novel two multi-epitope vaccines (MEVs) composed of CTL, HTL and B cell epitopes overlaps with potential to elicit humoral as well as cellular immune response against SARS-CoV-2. To enhance the immune response for our vaccine design, truncated (residues 10-153) Onchocerca volvulus activation-associated secreted protein-1 (Ov-ASP-1) has been utilized as an adjuvant at N terminal of both the MEVs. Further molecular models for both the MEVs were prepared and validated for their stable molecular interactions with Toll-Like Receptor 3 (TLR 3). The codon-optimized cDNA of both the MEVs were further analyzed for their potential of high level of expression in a human cell line. The present study is very significant in terms of molecular designing of prospective CTL and HTL vaccine against SARS-CoV-2 infection with the potential to elicit cellular as well as humoral immune response. (SARS-CoV-2), Coronavirus, Human Transporter associated with antigen processing (TAP), Toll-Like Receptor (TLR), Epitope, Immunoinformatics, Molecular Docking, Molecular dynamics simulation, Multi-epitope Vaccine Graphical abstractThe designed CTL (Cytotoxic T lymphocyte) and HTL (Helper T lymphocyte) multi-epitope vaccines (MEV) against COVID19 infection. Both the CTL and HTL MEV models show a very stable and well fit conformational complex formation tendency with the Toll like receptor 3. CTL and HTL MEVs: ribbon; Toll like receptor 3: gray cartoon; Adjuvant [truncated (residues 10-153) Onchocerca volvulus activation-associated secreted protein-1]: orange ribbon regions; Epitopes: cyan ribbons regions; 6xHis Tag: magenta ribbon regions. O_FIG O_LINKSMALLFIG WIDTH=87 HEIGHT=200 SRC="FIGDIR/small/019299v2_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@6cb749org.highwire.dtl.DTLVardef@1752d54org.highwire.dtl.DTLVardef@1f2fc16org.highwire.dtl.DTLVardef@18415a9_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

bioRxiv2019

Flagella methylation promotes bacterial adhesion and host cell invasion

The flagellum is the motility device of many bacteria and the long external filament is made of several thousand copies of a single protein, flagellin. While posttranslational modifications of flagellin are common among bacterial pathogens, the role of lysine methylation remained unknown. Here, we show that both flagellins of Salmonella enterica, FliC and FljB, are methylated at surface-exposed lysine residues. A Salmonella mutant deficient in flagellin methylation was outcompeted for gut colonization in a gastroenteritis mouse model. In support, methylation of flagellin promoted invasion of epithelial cells in vitro. Lysine methylation increased the surface hydrophobicity of flagellin and enhanced flagella-dependent adhesion of Salmonella to phosphatidylcholine vesicles and epithelial cells. In summary, posttranslational flagellin methylation constitutes a novel mechanism how flagellated bacteria facilitate adhesion to hydrophobic host cell surfaces and thereby contributes to efficient gut colonization and successful infection of the host.

microbiology↗

bioRxiv2019

Molecular organization of soluble type III secretion system sorting platform complexes

Many medically relevant Gram-negative bacteria use the type III secretion system (T3SS) to translocate effector proteins into the host for their invasion and intracellular survival. A multi-protein complex located at the cytosolic interface of the T3SS is proposed to act as a sorting platform by selecting and targeting substrates for secretion through the system. However, the precise stoichiometry and 3D organization of the sorting platform components is unknown. Here we reconstitute soluble complexes of the Salmonella Typhimurium sorting platform proteins including the ATPase InvC, the regulator OrgB, the protein SpaO and a recently identified subunit SpaOC, which we show to be essential for the solubility of SpaO. We establish domain-domain interactions, determine for the first time the stoichiometry of each subunit within the complexes by native mass spectrometry and gain insight into their organization using small-angle X-ray scattering. Importantly, we find that in solution the assembly of SpaO/SpaOC/OrgB/InvC adopts an extended L-shaped conformation resembling the sorting platform pods seen in in situ cryo-electron tomography, proposing that this complex is the core building block that can be conceivably assembled into higher oligomers to form the T3SS sorting platform. The determined molecular arrangements of the soluble complexes of the sorting platform provide important insights into its architecture and assembly.

microbiology↗