Background: HIV-infected adults are highly susceptible to pneumococcal disease.
Objective: To examine if alveolar macrophages from HIV-infected subjects exhibited a failure of cytokine production in response to Streptococcus pneumoniae in vitro.
Design: Case–control comparison of alveolar macrophages from 11 HIV-infected and 13 non-infected adults.
Methods: Type 1 opsonized S. pneumoniae were used to challenge the alveolar macrophages in vitro. Cell supernatant fluid was collected from unstimulated cells, and cells challenged with bacteria for 0, 6, 12 and 24 h. Cytokine production (interleukins 1β, 6 and 8) was measured in all fluids using an enzyme-linked immunosorbent assay.
Results: All the cytokines tested increased over time in both HIV-infected and uninfected subjects. Interleukin-8 release was significantly lower in HIV-infected than in non-HIV-infected subjects (P = 0.02).
Conclusion: Reduced interleukin-8 production may result in decreased neutrophil recruitment, and hence increased susceptibility to pneumococcal infection in HIV-infected subjects.
From the aMalawi–Liverpool–Wellcome Trust Research Programme, Universities of Malawi and Liverpool
bLiverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK
cDivision of Genomic Medicine, University of Sheffield Medical School, Royal Hallamshire Hospital, Sheffield, UK
dDepartment of Medicine, University of Malawi College of Medicine, Blantyre, Malawi.
Received 14 February, 2005
Revised 19 April, 2005
Accepted 17 May, 2005
Correspondence to Dr S. Gordon, Malawi–Liverpool–Wellcome Programme of Clinical Tropical Research, PO Box 30096, Blantyre, Malawi. E-mail: firstname.lastname@example.org; email@example.com.