Influence of the presence of mannose-binding lectin polymorphisms on the occurrence of leishmaniasis: a systematic review and meta-analysis.

BACKGROUND: Leishmaniasis is caused by an intracellular protozoan of the Leishmania genus. Mannose-binding lectin (MBL) is a serum complement protein and recognizes lipoprotein antigens in protozoa and the bacterial plasma membrane. Nucleotide variants in the promoter region and exon 1 of the MBL gene can influence its expression or change its molecular structure. OBJECTIVE: To evaluate, through a systematic review, case-control studies of the genetic association of variants in the MBL2 gene and the risk of developing leishmaniasis. METHODS: This review carried out a search in PubMed, Science Direct, Cochrane Library, Scopus and Lilacs databases for case-control publications with six polymorphisms in the mannose-binding Lectin gene. The following strategy was used: P = Patients at risk of leishmaniasis; I = Presence of polymorphisms; C = Absence of polymorphisms; O = Occurrence of leishmaniasis. Four case/control studies consisting of 791 patients with leishmaniasis and 967 healthy subjects (Control) are included in this meta-analysis. The association of variants in the mannose-binding Lectin gene and leishmaniasis under the allelic genetic model, -550 (Hvs. L), -221 (X vs. Y), +4 (Q vs. P), CD52 (A vs. D), CD54 (A vs. B), CD57 (A vs. C) and A/O genotype (A vs. O) was evaluated. International Prospective Register of Systematic Reviews (PROSPERO): CRD42020201755. RESULTS: The meta-analysis results for any allelic genetic model showed no significant association for the variants within the promoter, the untranslated region, and exon 1, as well as for the wild-type A allele and mutant allele O with leishmaniasis. STUDY LIMITATIONS: Caution should be exercised when interpreting these results, as they are based on a few studies, which show divergent results when analyzed separately. CONCLUSIONS: This meta-analysis showed a non-significant association between the rs11003125, rs7096206, rs7095891, rs5030737, rs1800450, and rs1800451 polymorphisms of the Mannose-binding Lectin gene and leishmaniasis in any allelic and heterogeneous evaluation.

Influence of the presence of mannose-binding lectin polymorphisms on the occurrence of leishmaniasis: a systematic review and meta-analysis

Abstract Background Leishmaniasis is caused by an intracellular protozoan of the Leishmania genus. Mannose-binding lectin (MBL) is a serum complement protein and recognizes lipoprotein antigens in protozoa and the bacterial plasma membrane. Nucleotide variants in the promoter region and exon 1 of the MBL gene can influence its expression or change its molecular structure. Objective To evaluate, through a systematic review, case-control studies of the genetic association of variants in the MBL2 gene and the risk of developing leishmaniasis. Methods This review carried out a search in PubMed, Science Direct, Cochrane Library, Scopus and Lilacs databases for case-control publications with six polymorphisms in the mannose-binding Lectin gene. The following strategy was used: P = Patients at risk of leishmaniasis; I = Presence of polymorphisms; C = Absence of polymorphisms; O = Occurrence of leishmaniasis. Four case/control studies consisting of 791 patients with leishmaniasis and 967 healthy subjects (Control) are included in this meta-analysis. The association of variants in the mannose-binding Lectin gene and leishmaniasis under the allelic genetic model, -550 (Hvs. L), -221 (X vs. Y), +4 (Q vs. P), CD52 (A vs. D), CD54 (A vs. B), CD57 (A vs. C) and A/O genotype (A vs. O) was evaluated. International Prospective Register of Systematic Reviews (PROSPERO): CRD42020201755. Results The meta-analysis results for any allelic genetic model showed no significant association for the variants within the promoter, the untranslated region, and exon 1, as well as for the wild-type A allele and mutant allele O with leishmaniasis. Study limitations Caution should be exercised when interpreting these results, as they are based on a few studies, which show divergent results when analyzed separately. Conclusions This meta-analysis showed a non-significant association between the rs11003125, rs7096206, rs7095891, rs5030737, rs1800450, and rs1800451 polymorphisms of the Mannose-binding Lectin gene and leishmaniasis in any allelic and heterogeneous evaluation.

Polymorphisms in the TOLLIP Gene Influence Susceptibility to Cutaneous Leishmaniasis Caused by Leishmania guyanensis in the Amazonas State of Brazil.

INTRODUCTION: The clinical outcome to Leishmania-infection is determined by the individual adaptive immune T helper cell responses and their interactions with parasitized host cells. An early development of a proinflammatory immune response (Th1 response) is necessary for Leishmania-infection resolution. The Toll-interacting protein (TOLLIP) regulates human Toll-like receptors signaling pathways by down regulating the proinflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) and inducing the ant-inflammatory cytokine interleukin-10 (IL-10). Polymorphisms in the TOLLIP gene are associated with infectious diseases. MATERIAL AND METHODS: The polymorphisms rs5743899 and rs3750920 in the TOLLIP gene were genotyped by polymerase chain reaction and restriction fragment length polymorphism (RFLP) analysis in 631 patients with cutaneous leishmaniasis (CL) caused by L. guyanensis and 530 individuals with no history of leishmaniasis. RESULTS: The G and T alleles of the rs5743899 and rs3750920 were more common in patients with CL than in healthy individuals (P = 2.6 x10(-8) ; odds ratio [OR], 1.7 [ 95% confidence interval (CI) 1.4-2.0] and P = 1.9 x10(-8) ; OR, 1.6 [95% CI 1.4-1.9] respectively). The r2 and D' linkage disequilibrium between the two polymorphisms are 0.05 and 0.473 with a confidence bounds of 0.37 to 0.57 respectively. CONCLUSION: The two polymorphisms are independently associated with an increased risk of developing CL.