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Background: Some diet additives have become alternatives to achieve higher yields within the productively sustainable, organic, and ecological margins. Hence, nutrients and microorganisms can be added to the diet for fish immunity improvements, by using the nutrients in the feed, which lead to a positive animal performance. Accordingly, the aim of this paper was to gather information related to the utilization of additives as immunostimulant in tilapia (Oreochromis ssp.), and their physiological performance in the body. Development: Many of these immunostimulants are microorganisms or habitual nutrients in the diet, such as polysaccharides, proteins or lipids, which at high concentrations are capable of creating a stimulating effect, speeding disease resistance through specific or unspecific mechanisms of immunological response, thus becoming primary prophylactic agents. Conclusions: The use of additives as immunostimulants helps prevent the occurrence of common diseases in tilapia culture, by modulating the intestinal system in the different species of genus Oreochromis, thus enhancing the unspecific immune response, and, in turn, some processes like individual growth, feeding efficiency, and stress tolerance can be favored. [ABSTRACT FROM AUTHOR]

The major histocompatibility complex (MHC) in chickens (Gallus gallus) is located on the 16th micro chromosome, of the avian genome. As in other species, it has a strong association with genetic resistance to diseases. This multigenic feature is particularly desired for the selection of this species, in particular because of its relationship with animal welfare. This paper aims to review the knowledge on the analysis of the variability of MHC-B in chickens and its analysis methodologies, and a synthesis of the work done on Campero INTA chickens. [ABSTRACT FROM AUTHOR]

During the lifetime, plants interact with numerous pests with diverse modes of attack and lifestyle. The primary immune response evolved toward the recognition of the organisms that interact with the plant and the translation of this recognition into a defense response specifically directed against the invading organism. In addition to this induction, plant defenses may also be primed. This kind of resistance often acts systemically throughout the plant and is effective against a broad spectrum of pests. There are different types of induced resistance, depending on the organism or inducer that interacts with the plant. The plant-signaling molecules salicylic (SA) and jasmonic acids (JA) play an important role in the induced disease resistance pathways with a possible antagonistic interaction between the SA-dependent systemic acquired resistance (SAR) pathway, which is induced upon pathogen infection, and the JA-dependent induced systemic resistance (ISR) pathway. In general, defense responses are vital but costly for plants. Thus, instead of maintaining them continuously, they can be primed and subjected to tight regulation, rapid activation, and spatial and temporal concentration, important factors for the success. However, the cost for this process should be analyzed in specific experimental designs that include the pathogen challenge. The aim of this paper is a simple approach to some concepts about the induced resistance, different induction alternatives, as well as possible inductors, signalling pathways and the resistance induced costs for the plant. [ABSTRACT FROM AUTHOR]

In this paper we show an extended model that describes the dynamic interaction between the immune response of a mammal and Tripanosoma cruzi parasite during the acute phase of a Chagas Disease. The model considers the immune and cellular response, plus the different stages (intracellular and extracellular) of T. cruzi inside of a mammal host. The analysis of the time evolution of populations is made obtaining phase diagrams to determine the stability of the steady states in terms of its parameters. The system gives two steady states, which are associated with the Healing and Chronic state of the disease. The dead case obtained before when only the humoral immune response is considered it gets disappeared. The fundamental implication of this result is the benefit that the cellular immune response produces for the host as for the parasite, since it allows to extend the life of the host, while extending the critical state of the disease without destroying the habitat of the parasite. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The immune response combines a series of signals and complex mechanisms to occur, which can be modulated and enhanced. This one according the popular knowledge is possible using plant extracts, being one of them the plant extract JV-001. This showed, in previous studies, the ability to activate and enhance the cellular immune response of murine origin, but its effect on human leukocyte level is unknown, so the objective of this work was to study the effect of JV-001 in human leukocytes. MATERIAL AND METHOD: In this paper was used heparinized blood of healthy males, at first instance, this was treated with NH4Cl 64% to obtain total leukocytes, and in another, separate the mononuclear fraction by Histopaque® gradient. The cells obtained were adjusted to 8x106; aliquots of 100 µL of JV-001 or PBS. The plate was incubated at 37°C for 30 minutes and then washed, the peroxidase remaining in each recipient was revealed and determined with Orthophenylenediamine and H2O2, expressing the proceeds as absorbance read at 450 nm. RESULTS: The results showed an increase in total leukocyte adhesion between 44.35% and 63.3%, expressed by obtaining a positive delta absorbance with respect to controls. DISCUSSION: The mechanism that increases the adhesion is unknown, but probably due to increased expression of integrins. It is important to note that this increase does not occur upon incubation of mononuclear or polymorphonuclear cells separately, suggesting that the active principle of JV-001 not only does not act directly on adherent cells. [ABSTRACT FROM AUTHOR]

Sporotrichosis is a subcutaneous mycosis caused by a dimorphic complex of fungi called Sporothrix schenkii; it is a common disease in our country and has been reported in all continents. This paper presents a proposal of clinical classification of sporotrichosis based on its immunologic behavior, and which is divided into two groups, the first one hyperergic/normergic that presents a normal immune response to the intradermic antigen (sporotrichin M) and poor parasitic forms, and includes the most frequent clinical pictures: cutaneous-lymphatic and fixed-cutaneous; the second group or hypoergic/normergic, with low or no response to the intradermic antigen and presence of yeasts, includes the less frequent clinical pictures with opportunistic behavior: cutaneous-disseminated (hematogenous), cutaneous-superficial, osteoarticular, pulmonar and visceral. [ABSTRACT FROM AUTHOR]