Mannose-binding lectin concentrations in people living with HIV/AIDS infected by HHV-8

Viviane Martha Santos de Morais1, Juliana Prado Gonçales1, Georgea Gertrudes de Oliveira Mendes Cahú1

  • 1Virology Division, Laboratory of Immunopathology Keizo Asami (LIKA), Federal University of Pernambuco, Recife, Pernambuco, Brazil.

BMC Immunology
|January 5, 2019
PubMed
Abstract

Insights

Mannose-binding lectin (MBL) levels were lower in HIV/HHV-8 coinfected individuals compared to HIV-only patients. Lower MBL concentrations correlated with higher HIV viral load, suggesting MBL consumption during coinfection.

Area of Science:

  • Immunology
  • Virology
  • Infectious Diseases

Background:

  • Mannose-binding lectin (MBL) is crucial for innate immunity, activating the complement system via the lectin pathway.
  • MBL's role in viral infections is established, but its influence in individuals with Human Immunodeficiency Virus (HIV) and Human Herpesvirus 8 (HHV-8) coinfection was previously unknown.

Purpose of the Study:

  • To investigate the association of MBL-deficient plasma concentrations in HIV-infected individuals with or without HHV-8 coinfection.
  • To correlate MBL plasma concentrations with HIV viral load and CD4+ T-cell counts in both patient groups.

Main Methods:

  • An analytical case-control study involving 245 people living with HIV/AIDS (PLWHA).
  • Plasma MBL concentrations were measured using ELISA, with values < 100 ng/ml defined as deficient.
  • Samples included 118 HIV/HHV-8 coinfected and 127 HIV monoinfected patients.

Main Results:

  • MBL-deficient plasma concentrations were found in 5.1% of coinfected and 3.2% of monoinfected patients (p=0.445).
  • Median MBL plasma concentrations were significantly lower in coinfected patients (2803 log10 ng/ml) compared to monoinfected patients (2959 log10 ng/ml) (p=0.001).
  • An inverse correlation was observed between MBL plasma concentrations and HIV viral load in both groups; no correlation with CD4 count was found.

Conclusions:

  • MBL deficiency was not significantly associated with HHV-8 coinfection in PLWHA.
  • HIV/HHV-8 coinfected patients exhibited lower MBL concentrations, inversely correlated with HIV viral load.
  • This suggests potential MBL consumption and reduction due to opsonization of HIV and HHV-8, leading to decreased circulating MBL levels.

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