Dexamethasone Regulates Macrophage and Cd4+Cd25+ Cell Numbers in the Chicken Spleen

Abstract

Dexamethasone (DEX) is a corticoid hormone that is experimentally used to mimic the effects of increased levels of endogenous corticosterone observed during the stress response. Currently, stress is considered one of the major predisposing factors for diseases in the poultry industry. The aim of this study was to analyze the effects of DEX and/or of a 20-fold coccidial vaccine dose on leukocyte phenotypes in the spleen and cecal tonsils of chickens. Twenty specific-pathogen-free (SPF) Leghorn chickens were divided into four groups: a non-treated group (NT), a DEX-treated group (Dex), a vaccinated group (V) and a DEX-treated+vaccinated group (Dex+V). On experimental day (ED) 42, each bird in the vaccinated groups received a anti-coccidial vaccine. DEX was injected in the birds of the Dex and Dex+V groups (0.9 mg/kg) onED42 and ED45. + cells in the spleen of birds of the V group was higher than those measured in the other experimental groups. Our data suggest that CD4 + CD25 + cells and macrophages might be influenced by DEX treatment in spleen, but not in the cecal tonsils of chickens inoculated with Eimeria.

Effects of Dexamethasone on the Morphometry and Biometry of Immune Organs of Broiler Chicken

“…DEX is an immunosuppressant drug that is widely used to study some stressor effects in development and course of poultry diseases (Shini et al, 2010). Being close to endogenous corticosteroids, DEX was supposed to induce effects similar to elevated concentration of corticosterone and trigger stress-related signaling pathways (Calefi et al, 2016). The effect of DEX on lymphocytes from the spleen, mesenteric and popliteallymphnodes was less pronounced (Jeklova et al, 2008).…”

Characterization of Chicken Leukocyte Subsets from Lymphatic Tissue by Flow Cytometry

“…However, accuracy of cell count determination so far cannot be validated as comparison with reference levels is hindered by missing of other studies investigating absolute leukocyte counts in chicken spleen or CT. Except for one study, quantifying the number of T regs in CT (22), only relative proportions of immune cells were analyzed in chicken spleen and CT until now (8,11,12,39–42). Frequencies of the certain leukocyte subsets found in the present study are well reflected by these studies (8,11,12,39–42) indicating the validation of the characterized leukocyte populations.…”

“…Except for one study, quantifying the number of T regs in CT (22), only relative proportions of immune cells were analyzed in chicken spleen and CT until now (8,11,12,39–42). Frequencies of the certain leukocyte subsets found in the present study are well reflected by these studies (8,11,12,39–42) indicating the validation of the characterized leukocyte populations. As relative counts may not accurately reflect clinically relevant leukocyte alterations further studies should determine absolute numbers of lymphatic leukocytes for a better knowledge of reference values in healthy animals and understanding of disease‐related changes in chickens' immune system.…”

Anatomical and Morphometric Criteria of Spleen in Matured Gallus gallus, forma domestica L., Columbia livia G., Coturnix coturnix L.

“…Небезпечним є використання продуктів птахівництва, забруднених залишковими кількостями антибіотиків; у цілому проблема якості та безпеки харчових продуктів є міжнародною [13]. Саме тому триває вивчення селезінки птахів на клітинному та ультрамікроскопічному рівні [14][15][16][17][18][19].…”