title: Intestinal IgA⁺ cell numbers as well as IgA, IgG, and IgM contents correlate with mucosal humoral immunity of broilers during supplementation with high fluorine in the diets.
abstract: Fluoride (F), a well-recognized harmful substance, is easily absorbed by the intestinal mucosa. The intestinal mucosal immune system is equipped with unique innate and adaptive defense mechanisms that provide a first line of protection against infectious agents. Meanwhile, immunoglobulins are the major secretory products of the adaptive immune system and their levels can be a strong indicator of a disease or condition. In this study, therefore, we investigated the effects of high dietary fluorine on the numbers of immunoglobulin A-positive (IgA(+)) cells in the lamina propria of intestines (duodenum, jejunum and ileum) by immunohistochemistry as well as on the contents of immunoglobulin A (IgA), immunoglobulin G (IgG), and immunoglobulin M (IgM) in the mucosa of intestines (duodenum, jejunum, and ileum) by enzyme-linked immunosorbent assay (ELISA). A total of 280 1-day-old healthy avian broilers were randomly divided into four groups and fed on a corn-soybean basal diet as control diet (fluorine 22.6 mg/kg) or the same basal diet supplemented with 400, 800, and 1,200 mg/kg fluorine (high fluorine groups I, II, and III) in the form of sodium fluoride (NaF) for 42 days. The experimental data showed that the numbers of IgA(+) cells as well as the IgA, IgG, and IgM contents were significantly decreased (P < 0.01 or P < 0.05) in the high fluorine groups II and III when compared with those of the control group. It was concluded that dietary fluorine in the range of 800-1,200 mg/kg significantly reduced the numbers of the IgA(+) cells and the contents of aforementioned immunoglobulins in the intestines (duodenum, jejunum, and ileum) of broilers, which could finally impact the mucosal humoral immune function in the intestines by a way that reduces the lymphocyte population and/or lymphocyte activation.
authors.affiliation: Key Laboratory of Animal Diseases and Environmental Hazards of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Luo
authors.forename: Hengmin
authors.initials: H
authors.lastname: Cui
authors.forename: Xi
authors.initials: X
authors.lastname: Peng
authors.forename: Jing
authors.initials: J
authors.lastname: Fang
authors.forename: Zhicai
authors.initials: Z
authors.lastname: Zuo
authors.forename: Junliang
authors.initials: J
authors.lastname: Deng
authors.forename: Juan
authors.initials: J
authors.lastname: Liu
authors.forename: Yubing
authors.initials: Y
authors.lastname: Deng
mesh_terms: D000818:Animals; D002452:Cell Count; D002645:Chickens / Q000276:immunology; D019587:Dietary Supplements; D004797:Enzyme-Linked Immunosorbent Assay; D005461:Fluorine; D056724:Immunity, Humoral; D007070:Immunoglobulin A / Q000737:chemistry*; D007074:Immunoglobulin G / Q000737:chemistry*; D007075:Immunoglobulin M / Q000737:chemistry*; D007413:Intestinal Mucosa / Q000737:chemistry* / Q000276:immunology / Q000648:ultrastructure
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D005461:Fluorine