Developmental and comparative immunology.
Publisher:
Pergamon Press.,. Tarrytown Ny : Elsevier Science
Frequency: Ten no. a year 2003-
Country: United States
Language: English
Start Year:1977 -
ISSN:
0145-305X (Print)
1879-0089 (Electronic)
0145-305X (Linking)
1879-0089 (Electronic)
0145-305X (Linking)
Impact Factor
2.9
2022
| NLM ID: | 7708205 |
| (DNLM): | D07980000(s) |
| (OCoLC): | 02712411 |
| Coden: | DCIMDQ |
| LCCN: | 77648752 |
| Classification: | W1 DE997PM |
Exploration of the Differential Expression Patterns of Immunoglobulin Heavy Chain Genes in Horses and Donkeys. This study investigated the immunoglobulins (IG) gene locus structure and expression diversity in local Chinese horse and donkey breeds, including Ningqiang, Guanzhong horses, and varieties such as Guanzhong, Jiami, and Northern Shaanxi donkey using genome alignment and high-throughput sequencing. The aim was to expand understanding of IG expression patterns in horses, donkeys, and their different breeds. The results revealed that the donkey IGH locus contains 117 VH genes (23 functional), 44 DH genes, and 8 JH genes, arranged in a VH-DH-JH sequence on chromosome 7, spanning approximately 1189...
Characterization of extracellular trap production and release by equine neutrophils in response to different stimuli. This study explores Neutrophil Extracellular Trap (NET) formation in equine neutrophils, which is crucial for eliminating infections and is implicated in various equine inflammatory diseases. We investigated the molecular pathways involved in NET release by equine neutrophils in response to stimuli. We use PMA, A23187, LPS, PAF, OZ, and cytokines, observing NET release in response to PMA, PAF, and A23187. In contrast, LPS, OZ, and the cytokines tested did not induce DNA release or did not consistently induce citrullination of histone 4. Peptidyl-arginine deiminase inhibition completely halted ...
Postnatal changes in epigenetic modifications of neutrophils of foals are associated with increased ROS function and regulation of neutrophil function. Neonates of all species, including foals, are highly susceptible to infection, and neutrophils play a crucial role in innate immunity to infection. Evidence exists that neutrophils of neonatal foals are functionally deficient during the first weeks of life, including expression of cytokine genes such as IFNG. We hypothesized that postnatal epigenetic changes were likely to regulate the observed age-related changes in foal neutrophils. Using ChIP-Seq, we identified significant differences in trimethylated histone H3 lysine 4, an epigenetic modification associated with active promoters and enhan...
Identification, characterization and bioactivity of tumor necrosis factor (TNF)-related apoptosis-inducing ligand from Equus caballus. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily and plays multifunctional roles in the immune system. In the present study, a homolog of TRAIL from the Mongolian horse (named ecTRAIL) was identified and characterized. The 870-bp open reading frame encodes a polypeptide of 289 amino acid residues with a predicted molecular weight of 33.47 kDa and pI of 8.47. The genomic structure of ecTRAIL shares a five-exon/six-intron arrangement similar to its orthologs. Multiple alignments show that ecTRAIL is a type II transmembrane protein with a t...
Identification and characterization of equine blood plasmacytoid dendritic cells. Dendritic cells (DC) are antigen-presenting cells that can be classified into three major cell subsets: conventional DC1 (cDC1), cDC2 and plasmacytoid DCs (pDC), none of which have been identified in horses. Therefore, the objective of this study was to identify and characterize DC subsets in equine peripheral blood, emphasizing on pDC. Surface marker analysis allowed distinction of putative DC subsets, according to their differential expression of CADM-1 and MHC class II. Equine pDC were found to be Flt3(+) CD4(low) CD13(-) CD14(-) CD172a(-) CADM-1(-) MHCII(low). The weak expression of CD4 on...
Equine immunoglobulins and organization of immunoglobulin genes. Our understanding of how equine immunoglobulin genes are organized has increased significantly in recent years. For equine heavy chains, 52 IGHV, 40 IGHD, 8 IGHJ and 11 IGHC are present. Seven of these IGHCs are gamma chain genes. Sequence diversity is increasing between fetal, neonatal, foal and adult age. The kappa light chain contains 60 IGKV, 5 IGKJ and 1 IGKC, whereas there are 144 IGLV, 7 IGLJ, and 7 IGLC for the lambda light chain, which is expressed predominantly in horses. Significant transcriptional differences for IGLV and IGLC are identified in different breeds. Allotypic and allel...
In contrast to other species, α-Galactosylceramide (α-GalCer) is not an immunostimulatory NKT cell agonist in horses. α-GalCer is a potent immunomodulatory molecule that is presented to NKT cells via the CD1 antigen-presenting system. We hypothesized that when used as an adjuvant α-GalCer would induce protective immune responses against Rhodococcus equi, an important pathogen of young horses. Here we demonstrate that the equine CD1d molecule shares most features found in CD1d from other species and has a suitable lipid-binding groove for presenting glycolipids to NKT cells. However, equine CTL stimulated with α-GalCer failed to kill cells infected with R. equi, and α-GalCer did not increase killing by C...
Diversity of immunoglobulin lambda light chain gene usage over developmental stages in the horse. To further studies of neonatal immune responses to pathogens and vaccination, we investigated the dynamics of B lymphocyte development and immunoglobulin (Ig) gene diversity. Previously we demonstrated that equine fetal Ig VDJ sequences exhibit combinatorial and junctional diversity levels comparable to those of adult Ig VDJ sequences. Herein, RACE clones from fetal, neonatal, foal, and adult lymphoid tissue were assessed for Ig lambda light chain combinatorial, junctional, and sequence diversity. Remarkably, more lambda variable genes (IGLV) were used during fetal life than later stages and I...
Developmental progression of equine immunoglobulin heavy chain variable region diversity. Humoral immunity is a critical component of the immune system that is established during fetal life and expands upon exposure to pathogens. The extensive humoral immune response repertoire is generated in large part via immunoglobulin (Ig) heavy chain variable region diversity. The horse is a useful model to study the development of humoral diversity because the placenta does not transfer maternal antibodies; therefore, Igs detected in the fetus and pre-suckle neonate were generated in utero. The goal of this study was to compare the equine fetal Ig VDJ repertoire to that of neonatal, foal, an...
Age-related changes in intracellular expression of IFN-γ and TNF-α in equine lymphocytes measured in bronchoalveolar lavage and peripheral blood. Diseases of the lower airways represent some of the most common conditions affecting horses of all ages, but the type and severity tends to follow the horses' age. The age-related dysregulation of pro-inflammatory cytokines may, in part contribute to the development of the diseases. Therefore, we hypothesize that the expression of pro-inflammatory cytokines increases with age. Peripheral blood mononuclear cells (PBMC) and bronchoalveolar lavage (BAL) cells from clinically healthy horses of different ages were used for the investigation. The cells were stimulated and the production of IFN-γ an...
The promoter region of interferon-gamma is hypermethylated in neonatal foals and its demethylation is associated with increased gene expression. While born with a limited production, foals' interferon-gamma (IFN-γ) expression increases after birth. The underlying mechanisms remain unknown. DNA methylation is considered to be involved. Therefore, the DNA methylation status of the Ifng promoter in CD4(+) cells from neonatal foal was determined using a methylation-specific PCR (MSP), and its relevance to IFN-γ mRNA expression was estimated. The effect of environment on the DNA methylation was also evaluated by comparing ponies that were kept in a barn versus those on pasture. The DNA in the Ifng promoter was hypermethylated and its deme...
The role of proliferation in the regulation of interferon gamma (IFNγ) expression in foals. Interferon-gamma (IFNγ) plays an important role against viral and intracellular bacterial infections and its production is deficient in foals. Cellular proliferation provides an opportunity for de novo gene expression, though little is known about its role in regulating IFNγ expression in foals. While stimulation of foal peripheral blood mononuclear cells (PBMCs) with concanavalin A (ConA) increased the frequency of IFNγ(+) cells, the overall percentage of IFNγ(+) cells remained below that of adults. By contrast, the proliferative response of foal PBMC was significantly greater than that o...
A comprehensive analysis of germline and expressed immunoglobulin repertoire in the horse. Based on the recently released horse genome, we have characterized the genomic organization of the horse Ig gene loci. The horse IgH locus in genomic scaffold Un0011 contains 40 D(H) segments, 8 J(H) segments and 50 V(H) segments. The Igkappa locus contains only a single C(kappa) gene, 5 J(kappa) segments and a 60 V(kappa) segments, whereas the Iglambda locus contains 7 C(lambda) genes each preceded by a J(lambda) gene segment. A total of 110 V(lambda) segments with the same transcriptional polarity as J(lambda)-C(lambda) were identified upstream of the J(lambda)-C(lambda) cluster. However, 34...
Induction of interleukin-4 production in neonatal IgE+ cells after crosslinking of maternal IgE. Transfer of maternal IgE antibodies to the neonate with the colostrum has been described in different mammalian species. Previous work in horses has shown that IgE bound to the surface of neonatal basophils is solely of maternal origin. However, the functional role of the maternal IgE transfer remained unclear. We hypothesized that maternal IgE mediates the onset of innate IL-4 production in equine neonatal basophils. Intracellular IL-4 production was measured in PBMC of newborn and older foals by flow cytometric analysis. A small population of IL-4(+) cells was observed in the peripheral bloo...
Expression of essential B cell genes and immunoglobulin isotypes suggests active development and gene recombination during equine gestation. Many features of the equine immune system develop during fetal life, yet the naïve or immature immune state of the neonate renders the foal uniquely susceptible to particular pathogens. RT-PCR and immunohistochemical experiments investigated the progressive expression of developmental B cell markers and immunoglobulins in lymphoid tissues from equine fetus, pre-suckle neonate, foal, and adult horses. Serum IgM, IgG isotype, and IgA concentrations were also quantified in pre-suckle foals and adult horses. The expression of essential B cell genes suggests active development and gene recombinati...
The effect of age and telomere length on immune function in the horse. Telomeres, specialized structures present at the ends of linear eukaryotic chromosomes, function to maintain chromosome stability and integrity. Telomeres shorten with each cell division eventually leading to replicative senescence, a process thought to be associated with age-related decline in immune function. We hypothesized that shortened PBMC telomere length is a factor contributing to immunosenescence of the aged horse. Telomere length was assessed in 19 horses ranging in age from 1 to 25 years. Mitogen-induced 3H-thymidine incorporation, total serum IgG, and pro-inflammatory cytokine exp...
Immunoglobulins and immunoglobulin genes of the horse. Antibodies of the horse were studied intensively by many notable immunologists throughout the past century until the early 1970's. After a large gap of interest in horse immunology, additional basic studies on horse immunoglobulin genes performed during the past 10 years have resulted in new insights into the equine humoral immune system. These include the characterization of the immunoglobulin lambda and kappa light chain genes, the immunoglobulin heavy chain constant (IGHC) gene regions, and initial studies regarding the heavy chain variable genes. Horses express predominately lambda light c...
The equine thymus microenvironment: a morphological and immunohistochemical analysis. We characterized herein the microarchitecture of the equine thymus along with post-natal development (6 months-->18 years). Thymuses showed an involutional process, beginning before the puberty and defined by five histological grades, which consider the progressive cortical thymocyte depletion, shrinkage and rearrangement of the epithelial network and increase in extracellular matrix (ECM). A second feature of the equine thymus was the presence of eosinopoiesis, erythropoiesis, mastocytopoiesis and plasmacytogenesis. Additionally, lymphatic vessels, full of lymphocytes, were particularly pr...
The effect of aging on T cell responses in the horse. Horses greater than 20 years of age exhibit alterations in their immune responses similar to those observed in other aged individuals. The purpose of this study was to characterize immunosenescence in a population of aged ponies. The peripheral blood mononuclear cells (PBMC) from aged ponies exhibited a decreased proliferative response to various mitogens that was not overcome by the addition of interleukin 2 (IL-2) to the cultures. No difference in overall expression of the IL-2 receptor was seen between young and aged ponies, though CD8(+) cells from aged ponies exhibited increased levels of...
Characterization of equine natural killer and IL-2 stimulated lymphokine activated killer cell populations. Natural killer (NK) cells are an important component of the innate immune system. Though intensively studied in humans and rodents. NK cells remain less well characterized in other species. Studies are often limited by the lack of specific cell markers; however, the mAb NK-5C6 has been suggested to recognize an evolutionarily conserved molecule on NK cells and reacts with cells from several species. This mAb was used in the current investigation to identify and characterize equine NK cells, and was found to label approximately 10% of peripheral blood lymphocytes (PBL). Two-color flow cytometry...
Characterization of five monoclonal antibodies specific for swine class II major histocompatibility antigens and crossreactivity studies with leukocytes of domestic animals. A set of five monoclonal antibodies (mAb) against porcine major histocompatibility complex (MHC), or swine leukocyte antigens (SLA), class II molecules has been characterized. These mAbs appear to recognize monomorphic determinants on SLA-DR (2F4, 1F12 and 2E9/13) and SLA-DQ (BL2H5 and BL4H2) molecules, as assessed by flow cytometry and immunoprecipitation. By Western blot, the 2F4, 1F12, BL2H5 and BL4H2 epitopes were located on the beta-chains of these molecules. mAbs 2F4 and 1F12 crossreact with leucocytes of dog, cattle, horse and human; mAbs 2E9/13, BL2H5 and BL4H2 bind leucocytes of cattl...
Comparative analysis of phagocytosis of fungal cells by insect hemocytes versus horse neutrophils. In this study, the phagocytic ability of Spodoptera exigua hemocytes was compared to horse neutrophils. In vitro assays showed that the insect granulocytes and horse neutrophils actively phagocytose FITC-labeled Paecilomyces farinosus blastospores opsonized with S. exigua hemolymph lectin or horse serum, respectively. Killing of fungal cells by the neutrophils and hemocytes was analyzed under in vitro conditions. Neutrophils reduced the growth of P. farinosus up to 65% whereas no fungicidal activity was observed with hemocyte monolayers. The production of oxygen metabolites by both phagocytic ...
Comparison of receptor properties of erythrocyte membrane glycoproteins. Membrane glycoproteins from horse, sheep, goat and bovine erythrocytes were solubilized and purified. These glycoproteins could be placed in three groups based on their degrees of glycosylation: The major bovine erythrocyte glycoprotein (BGII) had 77% sugar, the minor bovine glycoprotein (BGI) had 27% sugar and the others had approximately 50% sugar. Four of the glycoproteins aggregated in a uniform way in aqueous solution--one, BGII, did not. Four had similar subunit sizes of 25-34,000 daltons, but BGII was larger--55,000 daltons. Receptor functions (for plant and invertebrate lectins, antibo...
The activity of purine salvage pathway enzymes in murine and horse models of congenital and acquired dysimmunity. Previous studies of human congenital immunodeficiency states and in vitro observations of lymphocyte response to mitogens have implicated two purine salvage pathway enzymes, andenosine deaminase (ADA) and nucleoside phosphorylase (NP), as critical in the normal maturation and/or function of the immune system. Based on this information, ADA and NP activities were examined in a variety of congenital and acquired animal models of dysimmunity. The animals studied herein included: congenitally athymic (nude) mice; congenitally asplenic mice; congenitally athymic-asplenic mice; motheaten mice; New Z...