A 12 year old Caucasian female presented with malaise, pyrexia and painful bullous hemorrhagic skin lesions on both upper and lower extremities. She was the second child of a healthy unrelated Caucasian couple and her past medical history was unremarkable. Laboratory tests showed raised inflammatory markers and chest radiograph showed a left lower lobe collapse. She was started on intravenous b...

Mannose-binding lectin (MBL) is an innate immune system pattern recognition protein that kills a wide range of pathogenic microbes through complement activation. A substantial proportion of all human populations studied to date have MBL deficiency due to MBL2 polymorphisms, which potentially increases susceptibility to infectious disease. MBL binds numerous respiratory pathogens but the capsule...

This case report describes a 5-year-old boy who presented to the emergency department with clinical symptoms and chest X-ray findings suggestive of pneumonia. Further history revealed multiple other infections, and workup for immunodeficiency revealed a deficiency of mannose-binding lectin (MBL), a pattern recognition receptor involved in activation of the complement system. Innate immunodefici...

A critical first line of defense against infection is constituted by the binding of natural antibodies to microbial surfaces, activating the complement system via the classical complement activation pathway. In this function, the classical activation pathway is supported and amplified by two antibody-independent complement activation routes, i.e., the lectin pathway and the alternative pathway....

mannose-binding lectin (mbl) is a ca⁺² -dependent collagenous lectin, that is produced by liver and mediates innate immune responses by opsonization of pathogens. the serum level of mbl varies widely among healthy individuals, ranging from 0.05 µg/ml (or lower) to over 5 µg/ml, mainly depending on genetic variation. this study has examined promoter and exon 1 of mbl2 genotype among 117 iranian ...

Staphylococcus aureus is a major cause of severe nosocomial and community-acquired infections. Phagocytes and humoral molecules, including complement, have been proposed to cooperate in host defense against gram-positive bacteria. Circumstantial evidence indicates a role for complement, but this has not been formally defined. Complement activation is initiated by the classical, alternative, or ...

Mannose-binding lectin (MBL; also known as mannan-binding lectin) is an important component of innate immunity. MBL levels are mainly genetically determined. Low serum MBL levels and their cognate haplotypes have been associated with a wide range of infections. However, most subjects with MBL deficiency remain healthy. MBL deficiency is also associated with non-infectious diseases including sys...