Increases in GroES and GroEL from Lactobacillus acidophilus L-92 in response to a decrease in medium pH, and changes...

Area of Science:

• Immunology
• Microbiology
• Biochemistry

Background:

• Probiotics, like Lactobacillus acidophilus L-92 (L-92), are investigated for their immunomodulatory and anti-allergy properties.
• The impact of culture conditions, specifically media pH, on probiotic function and immune response is not fully understood.

Purpose of the Study:

• To investigate the anti-allergy effects of Lactobacillus acidophilus L-92 (L-92).
• To determine how media pH affects L-92's immunomodulatory properties and key cellular components.

Main Methods:

• Microarray and proteome analyses were employed to study changes in L-92 cells and splenocyte responses.
• L-92 cells were cultured at varying pH levels (e.g., 5.0 and 4.5) to assess cytokine release from splenocytes.
• Comparative transcriptome and proteome analyses focused on cell wall-associated components.

Main Results:

• Decreased media pH during L-92 cell growth led to increased release of IL-12 from splenocytes.
• Culturing L-92 at low pH (4.5) significantly altered cytokine profiles: increased IL-12, IFN-γ, IL-10, and decreased IL-4.
• Gene expression analysis revealed significant up-regulation (121 genes) and down-regulation (92 genes) at lower pH, with heat shock proteins (GroES, GroEL) identified as key factors.
• Proteome analysis confirmed increased cell wall-associated GroES and GroEL at lower pH.

Conclusions:

• Lowering the culture pH of Lactobacillus acidophilus L-92 enhances its immunomodulatory potential.
• Increased cell wall-associated proteins, specifically heat shock proteins GroES and GroEL, in L-92 at lower pH are linked to altered splenocyte cytokine release.
• These findings suggest that optimizing culture conditions for probiotics can modulate their anti-allergy effects.