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Related Experiment Video

Updated: Jul 6, 2026

The bm12 Inducible Model of Systemic Lupus Erythematosus (SLE) in C57BL/6 Mice

The bm12 Inducible Model of Systemic Lupus Erythematosus (SLE) in C57BL/6 Mice

Published on: November 1, 2015

The functional state of the complement system in leprosy.

Gabriela I Gomes¹, Edilbert P Nahn, Rose K R G Santos

¹Laboratório de Biologia do Reconhecer, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense-Darcy Ribeiro, Rio de Janeiro, Brazil.

The American Journal of Tropical Medicine and Hygiene

|April 4, 2008

Summary

Leprosy patients with the lepromatous form (LL) show complement system (CS) activation via the classic pathway (CP). This involves reduced C4 levels and higher mannose-binding lectin (MBL) levels, suggesting immune complex involvement.

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Last Updated: Jul 6, 2026

The bm12 Inducible Model of Systemic Lupus Erythematosus (SLE) in C57BL/6 Mice

The bm12 Inducible Model of Systemic Lupus Erythematosus (SLE) in C57BL/6 Mice

Published on: November 1, 2015

Area of Science:

Immunology
Infectious Diseases
Dermatology

Background:

Leprosy, caused by Mycobacterium leprae, presents diverse clinical forms.
The complement system (CS) plays a crucial role in immune responses.
Understanding CS activation in different leprosy forms is vital for disease management.

Purpose of the Study:

To investigate complement system activation pathways in various clinical forms of leprosy.
To identify specific complement components involved in lepromatous leprosy (LL).
To explore the role of mannose-binding lectin (MBL) in CS activation in LL.

Main Methods:

Assessed total complement system (CS) activity using hemolytic methods.
Quantified individual complement components via enzyme-linked immunosorbent assay (ELISA).
Analyzed sera from 91 leprosy patients (LL, TL, DL) and 31 healthy donors.

Main Results:

Significant CS consumption, specifically via the classic pathway (CP), was observed only in lepromatous leprosy (LL) patients.
LL patients exhibited reduced C4 levels but normal factor B (fB) and C3 levels.
Elevated serum mannose-binding lectin (MBL) levels were found in LL patients.

Conclusions:

The classic pathway (CP) of the complement system is implicated in CS activation in lepromatous leprosy (LL).
High serum MBL levels and circulating immune complexes likely initiate CS activation in LL patients.
These findings highlight a specific immune mechanism in the LL clinical form of leprosy.