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A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations

Celis‑Giraldo, Carmen Teresa; Bohórquez, Michel David; Camargo, Milena; Suárez, Carlos Fernando; Camargo, Anny; Rodríguez‑Obediente, Kewin; Martínez, Alejandra; Lucero, Carlos Edmundo; Hernández, Byron; Manzano‑Román, Raúl; Patarroyo, Manuel Elkin (2021)

Analysing pig class II mayor histocompatibility complex (MHC) molecules is mainly related to antigen presentation. Identifying frequently-occurring alleles in pig populations is an important aspect to be considered when ...
Babesia Bovis Ligand-Receptor Interaction: AMA-1 Contains Small Regions Governing Bovine Erythrocyte Binding

Cuy-Chaparro, Laura; Bohórquez, Michel David; Arevalo-Pinzon, Gabriela; Castañeda-Ramírez, Jeimmy Johana; Suárez, Carlos F. (2021)

Apical membrane antigen 1 is a microneme protein which plays an indispensable role during Apicomplexa parasite invasion. The detailed mechanism of AMA-1 molecular interaction with its receptor on bovine erythrocytes has ...
Identification of Babesia bovis MSA-1 functionally constraint regions capable of binding to bovine erythrocytes

Cuy Chaparro, Laura; Ricaurte-Contreras, Laura Alejandra; Bohórquez, Michel David; Arevalo-Pinzon, Gabriela; Barreto-Santamaría, Adriana; Pabón, Laura; Reyes, César; Moreno Pérez, Darwin Andrés; Patarroyo, Manuel-Alfonso (2022)

Merozoite surface antigen-1 is a glycoprotein expressed by Babesia bovis and is considered a vaccine candidate given that antibodies against it are able to partially block in vitro invasion of bovine erythrocytes. Despite ...
Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations

Bohórquez, Michel David; Ordoñez, Diego; Suárez, Carlos F.; Vicente, Belén; López Abán, Julio; Muro, Antonio; Ordóñez, Iván; Patarroyo, Manuel A. (2020)

Bovine leukocyte antigens (BoLA) have been used as disease markers and immunological traits in cattle due to their primary role in pathogen recognition by the immune system. A higher MHC allele diversity in a population ...

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A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations
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Celis‑Giraldo, Carmen Teresa | 2021

Analysing pig class II mayor histocompatibility complex (MHC) molecules is mainly related to antigen presentation. Identifying frequently-occurring alleles in pig populations is an important aspect to be considered when developing peptide-based vaccines. Colombian creole pig populations have had to adapt to local conditions since entering Colombia; a recent census has shown low amounts of pigs which is why they are considered protected by the Colombian government. Commercial hybrids are more attractive regarding production. This research has been aimed at describing the allele distribution of Colombian pigs from diverse genetic backgrounds and comparing Colombian SLA-DRB1 locus diversity to that of internationally reported populations. Twenty SLA-DRB1 alleles were identified in the six populations analysed here using sequence-based typing. The amount of alleles ranged from six (Manta and Casco Mula) to nine (San Pedreño). Only one allele (01:02) having > 5% frequency was shared by all three commercial line populations. Allele 02:01:01 was shared by five populations (around > 5% frequency). Global FST indicated that pig populations were clearly structured, as 20.6% of total allele frequency variation was explained by differences between populations (FST = 0.206). This study’s results confirmed that the greatest diversity occurred in wild boars, thereby contrasting with low diversity in domestic pig populations.

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Babesia Bovis Ligand-Receptor Interaction: AMA-1 Contains Small Regions Governing Bovine Erythrocyte Binding
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Cuy-Chaparro, Laura | 2021

Apical membrane antigen 1 is a microneme protein which plays an indispensable role during Apicomplexa parasite invasion. The detailed mechanism of AMA-1 molecular interaction with its receptor on bovine erythrocytes has not been completely defined in Babesia bovis. This study was focused on identifying the minimum B. bovis AMA-1-derived regions governing specific and high-affinity binding to its target cells. Different approaches were used for detecting ama-1 locus genetic variability and natural selection signatures. The binding properties of twelve highly conserved 20-residue-long peptides were evaluated using a sensitive and specific binding assay based on radio-iodination. B. bovis AMA-1 ectodomain structure was modelled and refined using molecular modelling software. NetMHCIIpan software was used for calculating B-and T-cell epitopes. The B. bovis ama-1 gene had regions under functional constraint, having the highest negative selective pressure intensity in the Domain I encoding region. Interestingly, B. bovis AMA-1-DI (100YMQKFDIPRNHGSGIYVDLG119 and120GYESVGSKSYRMPVGKCPVV139 ) and DII (302CPMHPVRDAIFGKWSGGSCV321 )-derived peptides had high specificity interaction with erythrocytes and bound to a chymotrypsin and neuraminidase-treatment sensitive receptor. DI-derived peptides appear to be exposed on the protein’s surface and contain predicted B-and T-cell epitopes. These findings provide data (for the first-time) concerning B. bovis AMA-1 functional subunits which are important for establishing receptor-ligand interactions which could be used in synthetic vaccine development.

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Identification of Babesia bovis MSA-1 functionally constraint regions capable of binding to bovine erythrocytes
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Cuy Chaparro, Laura | 2022

Merozoite surface antigen-1 is a glycoprotein expressed by Babesia bovis and is considered a vaccine candidate given that antibodies against it are able to partially block in vitro invasion of bovine erythrocytes. Despite this, no study to date has confirmed the target cell binding properties of the full MSA-1 or its fragments. This research has thus been focused on identifying protein regions playing a role in erythrocyte attachment, based on genetic diversity and natural selection analysis. Two regions under functional constraint (nucleotides 134–428 and 464–629) having a preponderance of negatively-selected signals were identified in silico. Three non-overlapping peptides derived from functionally constraint regions (42422 (39PEGSFYDDMSKFYGAVGSFD58), 42424 (91NALIKNNPMIRPDLFNATIV110) and 42426 (150TDIVEEDREKAVEYFKKHVY169)) were able to specifically bind to a sialoglycoprotein located on the bovine erythrocyte surface as confirmed by sensitive and specific peptide-cell interaction competition assays using both enzymatically treated and untreated red blood cells. Interestingly, it was predicted that peptides 42422 and 42426 have a helical structure and conserved motifs in all strain/isolates. These findings provide evidence, for the first time, related to B. bovis MSA-1 short regions used by the parasite in erythrocyte binding which could be predicted using natural selection analysis. Future work focused on evaluating these peptides’ antigenic ability during natural infection, and their ability to induce protection in immunisation assays are needed to confirm their usefulness as synthetic vaccine candidates.

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Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations
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Bohórquez, Michel David | 2020

Bovine leukocyte antigens (BoLA) have been used as disease markers and immunological traits in cattle due to their primary role in pathogen recognition by the immune system. A higher MHC allele diversity in a population will allow presenting a broader peptide repertoire. However, loss of overall diversity due to domestication process can decrease a population’s peptide repertoire. Within the context of zebu and taurine cattle populations, BoLA-DRB3 genetic diversity in Spanish Morucha and Colombian Normande cattle was analyzed and an approach to estimate functional diversity was performed. Sequence-based typing was used for identifying 29, 23, 27, and 28 alleles in Spanish Morucha, Nariño-, Boyacá-, and Cundinamarca-Normande cattle, respectively. These breeds had remarkably low heterozygosity levels and the Hardy-Weinberg principle revealed significant heterozygote deficiency. FST and DA genetic distance showed that Colombian Normande populations had greater variability than other phenotypically homogeneous breeds, such as Holstein. It was also found that Spanish Morucha cattle were strongly differentiated from other cattle breeds. Spanish Morucha had greater divergence in the peptide-binding region regarding other cattle breeds. However, peptide-binding region covariation indicated that the potential peptide repertoire seemed equivalent among cattle breeds. Despite the genetic divergence observed, the extent of the potential peptide repertoire in the cattle populations studied appears to be similar and thus their pathogen recognition potential should be equivalent, suggesting that functional diversity might persist in the face of bottlenecks imposed by domestication and breeding.

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Browsing by Author "Bohórquez, Michel David"

A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations ﻿

Babesia Bovis Ligand-Receptor Interaction: AMA-1 Contains Small Regions Governing Bovine Erythrocyte Binding ﻿

Identification of Babesia bovis MSA-1 functionally constraint regions capable of binding to bovine erythrocytes ﻿

Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations ﻿

Envíos recientes

A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations

Babesia Bovis Ligand-Receptor Interaction: AMA-1 Contains Small Regions Governing Bovine Erythrocyte Binding

Identification of Babesia bovis MSA-1 functionally constraint regions capable of binding to bovine erythrocytes

Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations

A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations

Babesia Bovis Ligand-Receptor Interaction: AMA-1 Contains Small Regions Governing Bovine Erythrocyte Binding

Identification of Babesia bovis MSA-1 functionally constraint regions capable of binding to bovine erythrocytes

Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations