[Persistent properties of Brucella abortus isolated from various sources]

Area of Science:

• Veterinary microbiology
• Immunology
• Infectious diseases

Background:

• Brucella abortus (B. abortus) is a significant zoonotic pathogen causing brucellosis in humans and animals.
• Understanding B. abortus persistence factors is crucial for developing effective control strategies.
• Previous studies have indicated variability in virulence among different B. abortus strains.

Purpose of the Study:

• To investigate the prevalence and manifestation of key persistence factors in a diverse collection of B. abortus strains.
• To determine if the source of B. abortus isolation correlates with the expression of specific persistence-related activities.
• To identify B. abortus populations with enhanced potential for survival and pathogenesis.

Main Methods:

• Seventy B. abortus strains were isolated from various sources, including cattle and human brucellosis patients.
• Antilysozyme activity was assessed to evaluate resistance to host innate immune components.
• Anticomplementary and anti-intercidal activities were measured to determine the capacity to evade complement-mediated killing and phagocytosis.

Main Results:

• Significant intraspecific variation in the expression of persistence factors was observed among the studied B. abortus strains.
• B. abortus strains isolated from cattle exhibited high levels of antilysozyme, anticomplementary, and anti-intercidal activities.
• Strains originating from human brucellosis patients demonstrated the most pronounced manifestation of these persistence factors.

Conclusions:

• The source of isolation significantly influences the expression of B. abortus persistence factors.
• B. abortus strains from cattle and human brucellosis cases possess enhanced mechanisms for immune evasion and survival.
• These findings highlight the importance of considering host-specific adaptations in B. abortus virulence and persistence.