title: Mannose-binding lectin gene variants and infections in patients receiving autologous stem cell transplantation.
abstract: BACKGROUND
  Serious infections are common in patients undergoing autologous stem cell transplantation (ASCT) mainly because of the effects of immunosuppression. The innate immune system plays an important role in the defense against different infections. Mannose binding lectin (MBL) is a central molecule of the innate immune system. There are several promoter polymorphisms and structural variants of the MBL2 gene that encodes for this protein. These variants produce low levels of MBL and have been associated with an increased risk for infections.
  
  
  METHODS
  Prospective cohort study. The incidence, severity of infections and mortality in 72 consecutive patients with hematologic diseases who underwent ASCT between February 2006 and June 2008 in a tertiary referral center were analyzed according to their MBL2 genotype. INNO-LiPA MBL2 was used for MBL2 gene amplification and genotyping. Relative risks (RR) (IC95%) as measure of association were calculated. Multivariate analysis was performed using logistic regression.
  
  
  RESULTS
  A statistically significant higher number of fungal infections was found in patients with MBL2 variants causing low MBL levels (21.1%versus1.9%, p=0.016). In this MBL2 variant group infection was more frequently the cause of mortality than in the MBL2 wild-type group (p=0.05). Although not statistically significant, there was a higher incidence of major infections in the MBL2 variant group as well as a higher number of infections caused by gram-positive bacteria.
  
  
  CONCLUSIONS
  Low-producer MBL2 genotypes were associated with an increased number of fungal infections in ASCT patients, which would suggest that MBL has a protective role against such infections. ASCT patients with MBL2 variant genotypes are more likely to die as a result of an infection.
authors.forename: Ana
authors.initials: A
authors.lastname: Moreto
authors.forename: Concepción
authors.initials: C
authors.lastname: Fariñas-Alvarez
authors.forename: Maria
authors.initials: M
authors.lastname: Puente
authors.forename: Javier Gonzalo
authors.initials: JG
authors.lastname: Ocejo-Vinyals
authors.forename: Pablo
authors.initials: P
authors.lastname: Sánchez-Velasco
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Horcajada
authors.forename: Ana
authors.initials: A
authors.lastname: Batlle
authors.forename: Carmen
authors.initials: C
authors.lastname: Montes
authors.forename: Francisca
authors.initials: F
authors.lastname: Santos
authors.forename: Eulogio
authors.initials: E
authors.lastname: Conde
authors.affiliation: Infectious Diseases Unit, Hospital Universitario Marqués de Valdecilla, University of Cantabria, IFIMAV, Santander, Spain. farinasc@unican.es.
authors.forename: Maria-Carmen
authors.initials: MC
authors.lastname: Fariñas
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005838:Genotype; D006402:Hematologic Diseases / Q000150:complications / Q000628:therapy; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects*; D006801:Humans; D007239:Infections / Q000209:etiology*; D008297:Male; D037601:Mannose-Binding Lectin / Q000235:genetics*; D037241:Mannose-Binding Lectins / Q000235:genetics*; D008875:Middle Aged; D014182:Transplantation, Autologous
chemical_list: C445619:MBL2 protein, human; D037601:Mannose-Binding Lectin; D037241:Mannose-Binding Lectins