Background: Previous studies demonstrated the effectiveness of combined milk antibody and prebiotic use in rheumatoid arthritis (RA)[1].

Objectives: Milk antibody and prebiotic, each modulating microbiota through mechanisms, are investigated to elucidate their combined therapeutic activity in RA via microbiota modulation.

Methods: Three groups of RA patients were assigned to receive skim milk (Skim Milk), milk antibody (Ab600), or a combination of both (Ab300) for 12 weeks. Fecal samples were analyzed for total bacteria and six bacterial species using real-time PCR, targeting Bifidobacterium, Lactobacillus, Bacteroides fragilis, E. coli, and Staphylococcus aureus. Fecal and serum lipopolysaccharides (LPS), and IgA and IgG antibodies against E. coli LPS were also measured.

Results: Correlation analysis of changes in bacterial counts over 12 weeks revealed 4/15 positive correlations in Skim Milk, 11/15 in Ab300, and 5/15 in Ab600. The 11/15 positive correlation rate in Ab300 was significantly higher than the other groups, suggesting potential mutualistic bacterial growth promotion in Ab300 may resolve dysbiosis in RA patients.

Further correlation analysis between RA disease markers (such as disease activity, LBP, TNF, IL-6) and bacterial counts showed that Bifidobacterium negatively correlated with IL-6 in Ab300, but positively in Ab600. Lactobacillus negatively correlated with DAS28-ESR, DAS28-CRP, IL-6, LBP in Ab300, and positively with DAS28-CRP in Ab600. These findings suggest that the probiotic effect in Ab300 is reversed in Ab600, indicating that mutualistic growth promotion in Ab300 may convert non-effective probiotics in RA into effective ones.

Clinical efficacy, based on the EULAR response criteria, showed 12, 13, and 8 responders in the Skim Milk, Ab300, and Ab600 groups, respectively. Clinical findings in responders included increased Bifidobacterium and Bacteroides, decreased serum LPS/fecal IPS ratio (indicating improved gut barrier), IL-6, ESR, Pain VAS in Skim Milk; increased Lactobacillus and Bacteroides, decreased serum LSP/fecal LPS ratio, IL-6 in Ab300; and decreased IgA anti-E. coli LPS antibody, Pain VAS, TNF in Ab600.

It is noted that Bifidobacterium and Lactobacillus can induce LPS tolerance[2], and Bacteroides can induce both LPS tolerance and masking[3]. These mechanisms could explain the observed responses in Skim and Ab300 groups. In Ab600 responders, reduced IgA anti-E. coli LPS antibodies suggest improved intestinal barrier[4], leading to TNF reduction.

Conclusion: The combination of milk antibody and prebiotic may provide a synergistic effect leading to LPS masking and tolerance in RA.

REFERENCES: [1] Possible linkage between intestinal bacteria composition changes and disease activity in patients with rheumatoid arthritis treated with natural milk antibodies against enteric bacteria and their toxins. K. Katayama Ann Rheum Dis, volume 77, supplement Suppl, year 2018, page A1406

[2] The effects of the probiotic cocktail on modulation of the NF-kB and JAK/STAT signaling pathways involved in the inflammatory response in bowel disease model

[3] Shadi Aghamohammad, Amin Sepehr, Seyedeh Tina Miri, Saeideh Najafi, Mahdi Rohani, Mohammad R. Pourshafiea

[4] BMC Immunol. 2022; 23: 8 doi: 10.1186/s12865-022-00484-6.PMID: 35240996

[5] Total Lipopolysaccharide from the Human Gut Microbiome Silences Toll-Like Receptor Signaling Eva d’Hennezel, Sahar Abubucker, Leon O. Murphy, Thomas W. Cullen mSystems. 2017 Nov-Dec; 2(6): e00046-17

[6] Contribution of bacterial pathogens to evoking serological disease markers and aggravating disease activity in rheumatoid arthritis

[7] Kuniaki Terato, Takaki Waritani, Richio Fukai, Hiroshi Shionoya, Hiroshi Itoh, Kou Katayama

[8] PLoS One. 2018; 13(2): e0190588.

Acknowledgements: NIL.

Disclosure of Interests: None declared.