Gene expression profiling in pbMEC - in search of molecular biomarkers to predict immunoglobulin production in bovine milk.

BACKGROUND: Optimization of the immunoglobulin (Ig) yield in bovine milk used as therapeutic immune milk or whey for the prevention of Clostridium difficile-associated diarrhea in humans is of great importance to improve the economic efficiency of production. Individual dairy cows have diverse immune responses upon vaccination, resulting in a variable Ig yield in blood and milk. Therefore, it is advisable to pre-select cows with the best ability to produce and secrete high yields of specific Igs. RESULTS: The gene expression profile of pbMEC (primary bovine mammary epithelial cells), challenged with the gram-positive, non-mastitis, pathogen Clostridium difficile showed distinct and significant differences in the gene expression of effector molecules of the innate immune system. A number of genes were identified that could possibly serve as molecular biomarkers to differentiate high responder cows from low responder cows. These identified genes play key roles in the promotion of innate immunity. CONCLUSION: Using a gene expression profiling approach, we showed that upon others, especially the gene expression of the pro-inflammatory cytokines was altered between the high and low responder cows. Those genes are indicated as potential molecular biomarkers in the pre-selection of cows that are able to secrete high immunoglobulin yields in milk.

Comparison of the immune competence of Turopolje, German Landrace × Turopolje, and German Landrace × Pietrain pigs after PRRSV vaccination.

The competences of the immune systems of the ancient pig breed Turopolje (T×T), German Landrace × Turopolje (L×T) and 'modern' pig breed German Landrace × Pietrain (L×P) were compared in this study. All pigs were immunized with a modified live vaccine against 'Porcine Reproductive and Respiratory Syndrome' (PRRS) virus (Ingelvac PRRS MLV(®)) to simulate an infection. Antibody production against PRRS MLV was evaluated in serum. Elimination of the viral infectious fragments during the experimental period was monitored in serum, leukocytes and tonsils by RT-qPCR. Furthermore relevant immune marker genes were quantified either on gene expression level using RT-qPCR [toll like receptor (TLR) 7, TLR8, TRAF6, CD163, SIGLEC1, CD4, CD8, CD14, CD19, tumor necrosis factor alpha (TNFα), interleukin (IL) 1, IL2, IL6, IL12], and on protein level using ELISA [interleukin (IL)-1, IL-2, IL-6, and IL-12]. The three breeds showed individual inactivation efficiencies as a reaction to the PRRS MLV vaccination. T×T eliminated the virus in serum within 16 days, followed by L×T (28 days) and L×P (36 days). The antibody titers against PRRS MLV of L×T and L×P were significantly higher compared to T×T (p<0.05). The gene expression data and protein analysis of interleukins revealed that T×T reacted with a type 1 immune response. In contrast, the two other breeds (L×T and L×P) showed a type 2 immune response, which resulted in the higher synthesis of B-cells and an increased concentration of specific anti-PRRS MLV antibodies.