Inhibition of lymphocyte blastogenesis by whey

Area of Science:

• Veterinary Immunology
• Dairy Science
• Molecular Biology

Background:

• Bovine mastitis is a significant concern in dairy farming.
• Understanding the immunological impact of mammary secretions is crucial for disease management.
• Lymphocyte function is a key indicator of immune status.

Purpose of the Study:

• To investigate the effects of bovine whey on lymphocyte blastogenesis.
• To characterize the inhibitory components in whey from mastitic cows.
• To determine the mechanism of whey-induced immunosuppression.

Main Methods:

• Lymphocyte-transformation tests were performed on bovine whey samples.
• DNA synthesis and blastogenesis were measured in lymphocytes stimulated with mitogens or bovine leukemia virus.
• Inhibitory molecules were tested for cytotoxicity, binding, and susceptibility to enzymatic degradation.
• The timing of whey exposure during lymphocyte stimulation was evaluated.

Main Results:

• Whey from clinical mastitis cases strongly inhibited lymphocyte DNA synthesis and blastogenesis.
• Whey from healthy glands showed minimal or no inhibitory effects.
• Inhibition was dose-dependent, non-cytotoxic, and involved minimal lymphocyte binding.
• Inhibitory factors were sensitive to proteolytic and glycolytic enzymes, suggesting a glycoprotein nature.
• Whey inhibited early-stage thymidine incorporation, but pre-incubation did not affect subsequent DNA synthesis.

Conclusions:

• Bovine whey, particularly from mastitic glands, contains immunosuppressive factors that impair lymphocyte function.
• These factors are likely glycoproteins and their inhibitory action is stage-specific during lymphocyte activation.
• Whey preparation methods can influence the observed inhibitory effects, highlighting the need for standardized assessment.