Blastogenic response of lymphocytes from foals infected with Rhodococcus equi.

The research article investigates how a bacterial infection in newborn foals affects their immune response. It was found that infection with Rhodococcus equi in the initial weeks post-birth results in decreased immune function in the infected foals.

Objective of the Study

• The primary aim of the study was to explore the blastogenic response of lymphocytes — a critical component of the immune response — from newborn foals infected naturally with Rhodococcus equi.
• This research aimed to clarify the potential relationship between R. equi infection and a depressed host response.

Methodology

• The study involved 16 newborn foals showing signs of R. equi infection at around 5-6 weeks of age.
• The infection was determined via clinical, haematological, bacteriological, and serological methods.

Results

• The research indicated a significantly decreased blastogenic response of lymphocytes to phytohaemagglutinin, a compound known to stimulate cell division, in the infected foals compared with unaffected foals. This was quantified by a stimulation index of less than 1.80.
• Furthermore, the concentration of serum Immunoglobulin G (IgG)— a type of antibody — significantly dropped once the foals reached an age of one week. The minimum levels of IgG were observed at 5-7 weeks, aligning with the noted onset of R. equi infection.

Conclusion

• The study suggests that the depressed immune function in naturally infected foals during the first 5-6 weeks after birth may be associated with the onset of R. equi infection.
• The indicated reduced blastogenic response and decreased IgG concentration point towards an overall decline in immune capacity in the infected foals compared to healthy ones.