Peripheral blood monocyte function in malnourished subjects with pulmonary tuberculosis

Area of Science:

• Immunology
• Nutritional Science
• Infectious Diseases

Background:

• Pulmonary tuberculosis (TB) is a global health concern.
• Malnutrition is frequently associated with TB and can affect immune function.
• Peripheral blood monocytes play a crucial role in cellular immunity.

Purpose of the Study:

• To investigate the effect of malnutrition on the in vitro functional status of peripheral blood monocytes in pulmonary tuberculosis patients and their contacts.
• To compare monocyte (MO) function, including hydrogen peroxide (H2O2), superoxide (O-2), and interleukin-1 (IL1) generation, among TB patients, contacts, and healthy controls.

Main Methods:

• Peripheral blood monocytes were isolated from pulmonary tuberculosis patients, their contacts, and healthy controls.
• Monocytes were activated in vitro.
• The capacity of activated monocytes to generate hydrogen peroxide (H2O2), superoxide (O-2), and interleukin-1 (IL1) was measured.

Main Results:

• Patients and contacts exhibited significantly poorer nutritional status compared to healthy controls.
• In vitro activated monocyte functions (H2O2, O-2, IL1 generation) were comparable across all three groups (TB patients, contacts, controls).
• This indicates a lack of in vivo monocyte activation in individuals with tuberculosis infection/disease.

Conclusions:

• Associated malnutrition in TB patients and contacts did not impair the in vitro functional capacity of their monocytes.
• The observed lack of in vivo monocyte activation may be linked to malnutrition-induced deficiencies in lymphokine elaboration.
• This immunological defect could elevate the risk of developing overt tuberculosis infection in malnourished contacts.