Anti-basement membrane glomerulopathy in experimental trypanosomiasis

Area of Science:

• Immunology
• Nephrology
• Parasitology

Background:

• Trypanosomiasis, a parasitic disease, can lead to kidney complications.
• The specific mechanisms of kidney damage in Trypanosoma brucei infections are not fully understood.

Purpose of the Study:

• To investigate the nature of kidney lesions in BD IX rats infected with Trypanosoma brucei.
• To identify the antibodies involved in the pathogenesis of kidney damage.

Main Methods:

• Induction of infection in rats.
• Measurement of proteinuria.
• Immunofluorescence microscopy to detect antibody deposition.
• Enzyme-linked immunosorbent assay (ELISA) and immunoblotting to determine antibody specificity.
• Indirect immunofluorescence to assess antigenic sites.

Main Results:

• Proteinuria developed and increased significantly by 7 weeks post-infection.
• Antibodies deposited on the glomerular basement membrane (GBM), initially linear, becoming granular.
• Anti-GBM antibodies detected in sera and kidney eluates.
• Antibodies reacted with GBM components laminin and type IV collagen, but not fibronectin.
• No common antigenic sites found between trypanosomes and GBM components.

Conclusions:

• Autoantibodies against GBM components (laminin, type IV collagen) are implicated in kidney lesions during trypanosomiasis.
• Linear immunofluorescence is due to antibodies targeting GBM components.
• Subendothelial complex formation may result from molecular rearrangement after antibody binding.
• Autoantibody formation is likely driven by polyclonal B cell stimulation common in trypanosomiasis.