# Impact of Lactic Acid Bacteria on Immunoreactivity of Oat Beers
## 3 Results and Discussion
The inability of gastric enzymes to cleave proline-glutamine bonds within gluten protein sequences leads to the formation of peptide fragments with a significant immunogenic potential, as they can induce an adverse immune response of varying intensity in genetically susceptible individuals [67]. The amount of gluten that can be tolerated by patients also vari  
Figure 5: Immunoreactivity of beers subjected to simulated digestion, determined with rabbit antibodies. X\({}_{\text{mean}}\)\(\pm\) SD, n = 6. Asterisks (*) indicate a statistically significant difference (\(p\) < 0.05) compared to the barley counterpart. pathologies. Surprisingly, patients with non-celiac gluten sensitivity may not tolerate even very low amounts of gluten [70]. The remaining, not fully digested gluten fraction can provoke an innate response or engage the immune system through an adaptive response. The innate immune response activated by certain gluten-derived peptides induces the production of interleukin-15 (IL-15), while the adaptive immune response is initiated by T cells recognizing specific gluten epitopes presented by antigen-presenting cells [71]. The assessments conducted with human antigliadin antibodies from CD patients revealed very diverse immune responses to oats, ranging widely from only 12% to 70%, which were specific to each individual. Such large variations in individual gluten hypersensitivity are typical among people with celiac disease. This is one of the reasons why it is difficult to clearly establish a safe dose of gluten for CD patients. According to various sources, the safe level is referred to in the range of 10-100 mg/day, with most specialists indicating a maximum threshold of 50 mg/day [20]. However, similarly to rabbit antibodies, for reactions with human sera, there was a statistically significant (\(p<0.05\)) reduction in the immune response to beer for all types of raw materials used. In oat beers digested with pepsin and pancreatin, the remaining immunoreactivity was as low as 0.6-2.0%. It can therefore be assumed that with such a low immune response, these beers would be well-tolerated by patients. This assumption is supported by reports indicating that patients with moderate gluten intolerance can tolerate occasional consumption of barley beers [20], for which, in this study, the mean value of the remaining immunoreactivity determined for the sera of the most sensitive patients exceeded 3%. What is more, adherence to a strict gluten-free diet is not mandatory for non-celiac gluten sensitivity patients, as sometimes it is sufficient to reduce the amount of gluten in the diet [21]. In addition to very large differences in the immune response to the tested beers among the group of patients subjected to the study, not all sera showed statistically significant differences (\(p<0.05\)) between the samples. Despite the relatively diverse specific characteristics of individual human sera, the changes in immunoreactivity observed with their use had a similar pattern to that seen in the case of rabbit antibodies. As reported by the Working Group on Prolamin Analysis and Toxicity [67], the experimental studies on  
Figure 6: Immunoreactivity of beers subjected to simulated digestion, determined with human antibodies. X\({}_{\text{mean}}\pm\) SD, n = 6. Asterisks (*) indicate a statistically significant difference (\(p<0.05\)) compared to the barley counterpart. animal models have demonstrated the effectiveness of certain lactobacilli in degrading immunogenic gluten peptides, thus alleviating small intestinal damage. Therefore, it seems crucial to search for LAB strains that demonstrate the ability to effectively hydrolyze toxic gluten sequences.