Model For Immunological Research Research Articles

The pig as a model for immunology research.

The pig is an omnivorous, monogastric species with many advantages to serve as an animal model for human diseases. There are very high similarities to humans in anatomy and functions of the immune system, e g., the presence of tonsils, which are absent in rodents. The porcine immune system resembles man for more than 80% of analyzed parameters in contrast to the mouse with only about 10%. The pig can easily be bred, and there are less emotional problems to use them as experimental animals than dogs or monkeys. Indwelling cannulas in a vein or lymphatic vessel enable repetitive stress-free sampling. Meanwhile, there are many markers available to characterize immune cells. Lymphoid organs, their function, and their role in lymphocyte kinetics (proliferation and migration) are reviewed. For long-term experiments, minipigs (e.g., Göttingen minipig) are available. Pigs can be kept under gnotobiotic (germfree) conditions for some time after birth to study the effects of microbiota. The effects of probiotics can be tested on the gut immune system. The lung has been used for extracorporeal preservation and immune engineering. After genetic modifications are established, the pig is the best animal model for future xenotransplantation to reduce the problem of organ shortage for organ transplantation. Autotransplantation of particles of lymphnodes regenerates in the subcutaneous tissue. This is a model to treat secondary lymphedema patients. There are pigs with cystic fibrosis and severe combined immune deficiency available.

Thymosin participates in antimicrobial immunity in zebrafish

Thymosin hormones, which were shown to be involved in immune system development and differentiation in previous studies, have antimicrobial functions in different animals. Zebrafish are a useful model for immunology research. Although thymosin has been reported to be involved in the embryonic development of zebrafish, it is necessary to uncover the antimicrobial function of thymosin in zebrafish. In this study, we expressed thymosin β (Tβ) in zebrafish in vitro and studied its antimicrobial function. The Tβ protein consists of 45 amino acids and is conserved among its family members, especially the actin-binding motif (LKKTET). Tβ was expressed in all tested tissues and was highly expressed in the brain, liver and hindgut. After Aeromonas hydrophila challenge, the Tβ transcript level increased in the skin, liver, kidney, spleen, thymus, foregut, gills and midgut. Purified recombinant thymosin β (rTβ) protein was used to study the antimicrobial mechanism. rTβ could inhibit the growth of Staphylococcus aureus, Aeromonas hydrophila, Vibrio anguillarum, Pseudomonas aeruginosa and Klebsiella pneumoniae. rTβ also binds to and agglutinates certain bacteria. Further study showed that rTβ could combine with the polysaccharides from gram-negative and gram-positive bacterial walls. All results suggested that the Tβ of zebrafish plays a significant role in innate antibacterial immune responses.

Zebrafish as a useful model for immunological research with potential applications in aquaculture

AbstractThe Zebrafish (Danio Rerio) is a Teleost fish, which offers several practical advantages concerning manipulation, maintenance and versatility as well as short life cycle, low cost and physiological similarity with most farmed species. Zebrafish have been used as model for several aquaculture‐relevant infectious agents, since the cost of infections to aquaculture can be great, making failure of immunity a major risk for commercial fish farming. This have allowed scientist to understand pathogens biology as well as fish immune response against infection, and thus have helped to improve disease control in aquaculture. This review summarizes the recent reports and main knowledge concerning the cellular and molecular aspects of the immune response in zebrafish and its potential applications in the fish farming industry. Several research results in zebrafish and other teleosts reveal that mucosal tissues have a strong and well‐structured immune response involving both innate and adaptive components. Together with the advantages of low maintenance cost, easy handling and genetic tools available, zebrafish comes up as a useful and reliable animal model for in vivo study of fish immune response and mechanisms as well as fish‐affecting infectious and inflammatory diseases which are a cause of concern for the aquaculture industry. Also, vaccines development, drugs screening and immunologically focused fish food assessment seem to be promising fields where zebrafish model can be used to generate positive impacts to the aquaculture practice.