Aleta™ – Proven Immune Modulating Effect
Research allows us to have a clear view on the mode of action of an animal’s immune system. Immune modulating feed ingredients, like a Beta-(1,3)-Glucan derived from an alga (Euglena gracilis), can be efficiently evaluated for their efficacy and mode of action through in vitro and in vivo studies.
The Importance of the Immune Response for Animal Health and Performance
When a pathogen invades an animal's body and multiplies, the animal may become sick, negatively affecting performance. Consequently, the immune system, which is protecting animals from infections, is primordial. It is protecting the animal in three different ways.
- First, it creates a physical barrier preventing viruses and bacteria from entering the body. The skin for example is an important part of the immune system. Skin acts as a boundary between germs and the body; it is impermeable to both viruses and bacteria.
- Second, should a virus or bacteria have the opportunity to enter an animal's body, the immune system attempts to both detect and eliminate it before it can reproduce. We are referring to the innate immunity, coming into action after few minutes contact with a pathogen, providing rapid protection.
- Third, should a virus or bacteria enter an animal's body and multiply, the immune system will start working to eliminate it. This is what we call the acquired immunity. It may take several days or weeks before this system becomes effective. It is no secret, once inside an animal's body, the immune system deals with the pathogen in various ways.
The presence of an Antigen Presenting Cell, like a macrophage or dendritic cell, combined with a T cell or B cell, is required to create an effective immune response to a pathogen. The antigen presenting cell (dendritic cell or macrophage) will take up a harmful substance and will process it. After processing, it will present it at its surface to other immune cells in order to create a further response. In addition, signal molecules (cytokines) are released by those APCs to trigger further reaction of other cells of the immune system. Antigen presenting cells (dendritic cells and macrophages) are thus crucial in inducing an immune response or boost. So, it is important to keep them in standby mode!
Cells of the immune system, including the antigen presenting cells (APC) like dendritic cells and macrophages, which are key cells in immune modulation, as both cells are possessing receptors binding Beta-(1,3)-Glucan and have the ability to respond by signal molecule release.
Aleta, a Beta-(1,3)-Glucan, Interacts Actively with Antigen Presenting Cells (APC)
The intense contact between gut content and immune cells located at the intestinal mucosa, summarized as the gut-associated lymphoid tissue (GALT), offers opportunities to modulate intestinal immunity via feed ingredients. One tool to keep APCs in standby mode is to expose them to a dietary supplement with proven scientific action. APCs are specialized to recognize substances that could be harmful for the animal, in particular specific molecular patterns belonging to a yeast or bacteria like for example carbohydrate structures. Beta-glucans are ideal candidates as they are present as a structural component in certain pathogens, so-called pathogen-associated molecular patterns. Beta-glucans are naturally occurring polysaccharides consisting of a 1,3-linked glucose backbone, which are recognized by the receptors on the antigen presenting cells.
Aleta, which is a pure and highly bioavailable algae-based solution which provides a high and consistent concentration of Beta-(1,3)-Glucan, is efficiently recognized and processed by APCs, consequently providing immune modulatory activities. This finding was proven in the following trial.
Mouse macrophages were incubated with and without fluorescently labeled Aleta (green) for 2 hours, unbound particles were washed away, and cells were incubated for 72 hours longer and then stained for macrophage marker (Cd11b – red) and nucleus marker (DAPI-blue) before imaging by confocal microscopy. These images clearly demonstrate that Aleta granules are readily phagocytosed by macrophages.
To go one step further, proving macrophages are releasing cytokines in response to Aleta, another trial was conducted. Mice were given Aleta for seven days. On day eight, macrophages were isolated from small intestine by magnetic sorting, cultured overnight, and the supernatants were tested for various signal molecules by a luminex multiplex assay. It was clear several cytokines were released in a dose-dependent response: IL-6, IL-1, TNF-α, IL-10, IL-18, Rantes, MIP-1, IP-10, MCP-1, … Those cytokines are regulatory or stimulating innate as well as acquired immunity or attracting other immune cells to the site.
The concept of immune modulation is clearly born with Aleta!
Fluorescently labeled macrophage (macrophage marker Cd11b for their surface (red) and DAPI for the nucleus (blue)) and Aleta (green) imaged by confocal microscopy, showing Aleta is actively ingested by macrophages, THE scientific proof of its mode of action!