Publications by authors named "Fidel Herrera"

Teleost IgT/Z plays a principal role in the defense mechanisms against infectious agents in the mucosal compartments and in systemic immunity. Previously, Nile tilapia () IgT was discovered and characterized at transcription level. In this work, we generated a monoclonal antibody (mAb) that specifically recognized the Nile tilapia IgT.

View Article and Find Full Text PDF

Growth Hormone-Releasing Peptide 6 (GHRP-6) (His-(D-Trp)-Ala-Trp-(D-Phe)-Lys-NH2) is an agonist of the growth hormone secretagogue receptor. GHRP-6 mimics the effect of ghrelin. The present study focuses on the immunomodulatory effects of GHRP-6 in tilapia with and without the presence of Pseudomonas aeruginosa infection.

View Article and Find Full Text PDF

Nile tilapia (Oreochromis niloticus) is a freshwater fish, which is extensively cultivated worldwide and constitutes one of the model species for the study of fish immunology. Monoclonal antibodies are very advantageous molecular tools for studying teleost immune system. Specifically, monoclonal antibodies that react with immunoglobulins are used successfully in the study of the humoral immune response of several fish species.

View Article and Find Full Text PDF

Immunoglobulin molecules play an important role in the immune defense system in all jawed vertebrates, by protecting the organism from a wide variety of pathogens. Nile tilapia (Oreochromis niloticus) is extensively cultivated worldwide, with a strong established market demand. It constitutes one of the model species for the study of fish immunology and its genome is currently fully sequenced.

View Article and Find Full Text PDF

Growth hormone (GH) release is a process that is well regulated by several factors, including GH secretagogues. GH can mediate the regulation of the fatty acid level and composition. The aim of this study was to determine the effect of a synthetic GH secretagogue peptide (A233) on the growth and fatty acid composition in tilapia (Oreochromis niloticus).

View Article and Find Full Text PDF

Interferon gamma (IFN-γ) has important roles in both innate and adaptive immune responses. This cytokine plays a very important role in defining Th1 immune response in all vertebrates. In the present study, we identified and isolated for the first time the gene coding for Nile tilapia (Oreochromis niloticus) IFNγ from spleen lymphocytes.

View Article and Find Full Text PDF

Modern subunit vaccines have excellent safety profiles and improved tolerability, but do not elicit strong immune responses without the addition of adjuvants. Developing a safe and affective adjuvant remains a challenge for peptide-based vaccine design. Growth Hormone Releasing Peptide-6 (GHRP-6) is one of the earliest-developed, synthetic, peptidyl growth hormone secretagogue receptor agonists.

View Article and Find Full Text PDF

In teleosts fish, secretion of GH is regulated by several hypothalamic factors that are influenced by the physiological state of the animal. There is an interaction between immune and endocrine systems through hormones and cytokines. GH in fish is involved in many physiological processes that are not overtly growth related, such as saltwater osmoregulation, antifreeze synthesis, and the regulation of sexual maturation and immune functions.

View Article and Find Full Text PDF

To date, many technologies have been developed to increase efficiency in aquaculture, but very few successful biotechnology molecules have arrived on the market. In this context, marine biotechnology has an opportunity to develop products to improve the output of fish in aquaculture. Published in vivo studies on the action of the pituitary adenylate cyclase-activating polypeptide (PACAP) in fish are scarce.

View Article and Find Full Text PDF

In a previous study, we unexpectedly found that tilapia growth hormone (tiGH) secreted to the culture media by transformed cells of the yeast Pichia pastoris lacks 46 amino acids from the C-terminal end. In the present study, we cloned the exact fragment that code for this truncated variant and demonstrated its growth promoting activity in goldfish when it's administered by immersion bath. Furthermore, a better characterization of this polypeptide was performed.

View Article and Find Full Text PDF

Neuropeptide Y, a 36 amino acid peptide abundantly expressed in the brain, is the most potent orexigenic factor known to date in mammals. It has been shown to be one of the most conserved neuropeptides in vertebrate evolution. It seems that neuropeptide Y functions, in addition to sequence conservation, are also well conserved in fish.

View Article and Find Full Text PDF