Mannose-binding lectin deficiency and miscarriages in rheumatoid arthritis

Area of Science:

• Immunogenetics
• Reproductive Medicine
• Rheumatology

Background:

• Rheumatoid arthritis (RA) is an autoimmune disease that can affect women of reproductive age.
• Mannose-binding lectin (MBL) plays a crucial role in the innate immune system.
• MBL serum levels are influenced by genetic polymorphisms in the MBL2 gene.

Purpose of the Study:

• To investigate the association between serum mannose-binding lectin (MBL) levels and MBL2 gene polymorphisms.
• To determine the frequency of spontaneous miscarriages in patients with rheumatoid arthritis (RA).
• To explore the relationship between MBL levels, MBL2 polymorphisms, and miscarriage occurrence in RA patients.

Main Methods:

• Study included 177 women with RA from Southern Brazil.
• MBL serum levels were quantified using ELISA.
• MBL2 gene polymorphisms (promoter, 5' untranslated region, exon 1) were genotyped via sequencing.

Main Results:

• Patients with a history of miscarriage exhibited significantly lower MBL median levels and a higher frequency of MBL deficiency compared to those without miscarriage history.
• RA patients experiencing miscarriage were more likely to carry MBL2 haplotypes associated with low MBL production.
• Specific MBL2 gene variations, including the LYPB haplotype and the O allele, were significantly associated with an increased risk of miscarriage.

Conclusions:

• MBL deficiency is identified as a potential risk factor for spontaneous miscarriage in women with rheumatoid arthritis.
• Specific MBL2 gene polymorphisms that result in MBL deficiency are associated with an increased likelihood of miscarriage in RA patients.
• These findings suggest an immunogenetic link between MBL function and pregnancy outcomes in rheumatoid arthritis.