1
|
Bjørgen H, Koppang EO. The melano-macrophage: The black leukocyte of fish immunity. FISH & SHELLFISH IMMUNOLOGY 2024; 148:109523. [PMID: 38522495 DOI: 10.1016/j.fsi.2024.109523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 03/26/2024]
Abstract
Melanin and the process of melanin synthesis or melanogenesis have central roles in the immune system of insects, and production of melanin-synthesizing enzymes from their haemocytes may be induced following activation through danger signals. Melanin-containing macrophage-like cells have been extensively studied in amphibians and they are also present in reptiles. In fish, melano-macrophages are especially recognized with respect to melano-macrophage centres (MMCs), hypothesized to be analogues of germinal centres in secondary lymphoid organs of mammals and some birds. Melano-macrophages are in addition present in several inflammatory conditions, in particular melanised focal changes, or black spots, in the musculature of farmed Atlantic salmon, Salmo salar. Melanins are complex compounds that may be divided into different forms which all have the ability to absorb and scatter light. Other functions include the quenching of free radicals and a direct effect on the immune system. According to the common view held in the pigment cell community, vertebrate melanin synthesis with melanosome formation may only occur in cells of ectodermal origin. However, abundant information suggests that also myeloid cells of ectothermic vertebrates may be classified as melanocytes. Here, we discuss these opposing views and review relevant literature. Finally, we review the current status on the research concerning melanised focal muscle changes that represent the most severe quality problem in Norwegian salmon production, but also other diseases where melano-macrophages play important roles.
Collapse
Affiliation(s)
- Håvard Bjørgen
- Unit of Anatomy, Veterinary Faculty, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Erling Olaf Koppang
- Unit of Anatomy, Veterinary Faculty, Norwegian University of Life Sciences (NMBU), Ås, Norway.
| |
Collapse
|
2
|
Yan D, Li G, Zhang H, Xue Q, Zhou C, Jiang Y, Yin J, Wang Z, Zhao W, Han W. Metagenomic Sequencing Revealed Differences in the Composition of Cecal Microbes in Different Breeds of Chickens. Animals (Basel) 2023; 14:28. [PMID: 38200759 PMCID: PMC10778133 DOI: 10.3390/ani14010028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 12/16/2023] [Accepted: 12/17/2023] [Indexed: 01/12/2024] Open
Abstract
Intestinal microorganisms are closely related to the health, development, and production performance of animals and can also provide basic information for us to fully understand and explore the germplasm characteristics and traits of local chicken breeds. In this experiment, we used five local Chinese chicken breeds as research materials; metagenomic sequencing technology was used to explore the differences in the composition of intestinal microorganisms in different breeds, and it was found that each local chicken breed had unique unigenes, of which Silkies had the most, with a total of 12,948. GO and KEGG analyses found that the biological processes most enriched by differential functional genes include genetic coding, macromolecular transport, protein synthesis, and molecular functions such as glycoprotein binding, protein hydrolysis, etc. Each breed is enriched with specific pathways, such as Anyi tile-like gray chickens, which are enriched with pathways related to disease resistance, while Gamecocks' enrichment is related to amino acid metabolism. Random Forest and LEfSe analyses revealed specific species of intestinal microorganisms in the cecum of different breeds, such as Exiguobacterium, which is associated with melanin deposition in Silkies. Therefore, we infer that gut microorganisms are closely related to the formation of chicken breed characteristics, and the results of this experiment can provide a theoretical basis for the discovery of high-quality traits and the improvement of feeding conditions in the future.
Collapse
Affiliation(s)
- Dan Yan
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China
| | - Guohui Li
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| | - Huiyong Zhang
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| | - Qian Xue
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| | - Chenghao Zhou
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| | - Yixiu Jiang
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| | - Jianmei Yin
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| | - Zhixiu Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China
| | - Wenming Zhao
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225000, China
| | - Wei Han
- Jiangsu Institute of Poultry Science, National Chickens Genetic Resources, Yangzhou 225125, China; (D.Y.); (G.L.)
| |
Collapse
|