Immunomodulatory effect of fosfomycin on human B-lymphocyte function

Area of Science:

• Immunology
• Microbiology
• Pharmacology

Background:

• Fosfomycin (FOM) is a unique antibiotic with no known chemical relatives.
• Recent studies indicate FOM inhibits histamine release from basophils.
• The impact of FOM on human B-cell functions remains largely unexamined.

Purpose of the Study:

• To investigate the effects of Fosfomycin (FOM) on human B-cell functions.
• To determine if FOM influences B-cell proliferation, cell cycle progression, and immunoglobulin secretion.

Main Methods:

• Human B cells were stimulated with Staphylococcus aureus Cowan 1.
• Cell proliferation was assessed using cell cycle analysis.
• Immunoglobulin secretion and cell surface antigen expression (CD25, CD71, Ia) were measured.

Main Results:

• FOM demonstrated a dose-dependent inhibition of B-cell proliferation induced by S. aureus Cowan 1.
• FOM caused cell cycle arrest at the G0 to G1 transition.
• FOM suppressed immunoglobulin secretion from antibody-producing B cells.
• FOM did not inhibit the expression of CD25 or CD71 activation antigens.
• FOM sustained increased Ia expression on B cells stimulated by S. aureus Cowan 1.

Conclusions:

• Fosfomycin (FOM) significantly impairs human B-cell proliferation and antibody production.
• FOM-induced cell cycle arrest affects both resting and activated B cells.
• FOM's sustained Ia expression suggests it may not hinder B-cell antigen presentation capabilities.