Detection of T Lymphocytes in Intestine of Broiler Chicks Treated with Lactobacillus spp. and Challenged with Salmonella enterica Serovar Enteritidis

Abstract

The expression of immune response in the form of leukocytic infiltrate by CD3+, CD4+, and CD8+ cells in the epithelium and in the intestinal lamina propria of chicks was studied in the present work by means of immunohistochemical reaction. The chicks were treated with Lactobacillus spp. or cecal microflora (CM) and experimentally challenged or not with Salmonella enterica serovar Enteritidis. The 320 birds utilized were divided into 4 groups containing 80 chicks each and submitted to treatments with Lactobacillus reuteri, Lactobacillus salivarius, Lactobacillus acidophilus, and CM. Each group was subdivided into 4 subgroups of 20 birds each and classified into a subgroup that did not receive treatment (negative control), subgroup treated, subgroup treated and challenged with Salmonella Enteritidis, and subgroup only challenged with Salmonella Enteritidis (positive control). The results obtained show that the treatment with L. reuteri, L. salivarius, L. acidophilus, or CM and challenged or not with Salmonella Enteritidis determine immune response in the form of leukocytic infiltrate by CD3+ and CD8+ lymphocytes followed by CD4+ in the epithelium and in the lamina propria of the duodenum, jejunum, and cecum of chicks up to 12 d of age. The quantity of CD3+ lymphocytes was significantly higher (P < 0.05) in the intestine of chicks treated with L. acidophilus or CM and challenged or not with Salmonella Enteritidis; however, the higher quantity of CD8+ lymphocytes was in the intestine of chicks treated with CM and challenged with Salmonella Enteritidis. The duodenum was the segment in which the immune response by T cells (CD3+, CD4+, and CD8+) was stimulated with the greatest intensity, followed by, respectively, the jejunum and cecum. The quantity of CD3+ lymphocytes present in the duodenum, jejunum, and cecum increases with the age of chicks, independent of the stimulus determined by treatments or challenge.

Effects of Probiotics on the Localization of T Cell Subsets in the Intestine of Broiler Chicks

“…Thus, it is likely that many of probiotic bacteria cause an increase in the density of T cells, especially CD8+ T cells, in the intestinal mucosa of the chicks. Also, such effects of probiotics in the chicks are likely to appear around 7 days after treatment as observed in the current study and by Yurong et al (2005) and Noujaim et al (2008). Although the mechanism by which CD8+ T cells population was enhanced by probiotics in the current study remains unknown, we assume that probiotics might induce some chemokine-or cytokine-like factors affect CD8+ T cells to lead to redistribution of CD8+ T cells from lymphoid tissue to the intestinal mucosa.…”

“…They showed a higher content of IgA in the intestinal fluid, greater frequencies of IgA-forming cells in the duodenum and T cells in the cecum tonsil at day 7 of treatment. Noujaim et al (2008) also showed a greater quantity of CD3+, CD4+ and CD8+ T cells in the intestine of chicks after 8 to 12 days of treatment with Lactobacillus spp. Thus, it is likely that many of probiotic bacteria cause an increase in the density of T cells, especially CD8+ T cells, in the intestinal mucosa of the chicks.…”

“…phase of post-hatching. Noujaim et al (2008) reported that treatment of chicks with Lactobacillus spp. resulted into a greater quantity of CD4+ T cells at day 12, and of CD8+ T cells at day 8 and 12.…”

“…Although the function of T cells expressing TCRγδ has not been fully established, they may have significant roles in the intestinal mucosal immune-system since they appear frequently in the intestinal mucosa (Chen et al, 1994). Noujaim et al (2008) reported that population of CD3+, CD4+ and CD8+ T cells were increased in the duodenum, jejunum and cecum by feeding with 3 different lactobacillus spp. or cecal microflora.…”

Effects of Probiotics on the Expression and Localization of Avian β-defensins in the Proventriculus of Broiler Chicks

“…These results suggest that probiotics may not have a significant effect on AvBD12 expression, but it is possible that the secretion of AvBD12 by the surface epithelium is stimulated by probiotics. Infection by pathogenic agents such as Salmonella and Campylobacter has been shown to increase the expression of chemokines, proinflammatory cytokines (Withanage et al, 2004;Carvajal et al, 2008) and cellular immunoresponse, particularly Th1 response (Berndt et al, 2007;Noujaim et al, 2008). In addition, infection by Salmonella may also upregulate the AvBDs expression in chick cecal tissue (Akbari et al, 2008;Wigley, 2013).…”