Logo image
A practical method for preparation of pneumococcal and nontypeable Haemophilus influenzae inocula that preserves viability and immunostimulatory activity
Journal article   Open access   Peer reviewed

A practical method for preparation of pneumococcal and nontypeable Haemophilus influenzae inocula that preserves viability and immunostimulatory activity

L.S. Kirkham, K.J. Corscadden, S.P. Wiertsema, A.J. Currie and P.C. Richmond
BMC Research Notes, Vol.6(1)
2013
pdf
pneumococcal_and_nontypeable_Haemophilus_influenzae_inocula.pdfDownloadView
Published (Version of Record) Open Access
url
Link to Published Version *Subscription may be requiredView

Abstract

Convenience is a major reason for using killed preparations of bacteria to investigate host-pathogen interactions, however, host responses to such preparations can result in different outcomes when compared to live bacterial stimulation. We investigated whether cryopreservation of Streptococcus pneumoniae and nontypeable Haemophilus influenzae (NTHi) permitted investigation of host responses to infection without the complications of working with freshly prepared live bacteria on the day of experimental challenge. Findings S. pneumoniae and NTHi retained >90% viability following cryopreservation in fetal calf serum for at least 8 weeks. Host responses to live, cryopreserved (1 week and 4 weeks), heat-killed or ethanol-killed S. pneumoniae and NTHi were assessed by measuring cytokine release from stimulated peripheral blood mononuclear cells (PBMCs). We found that cryopreserved bacteria, in contrast to heat-killed and ethanol-killed preparations, resulted in comparable levels of inflammatory cytokine release from PBMCs when compared with fresh live bacterial cultures. Conclusion Cryopreservation of S. pneumoniae and NTHi does not alter the immunostimulatory properties of these species thereby enabling reproducible and biologically relevant analysis of host responses to infection. This method also facilitates the analysis of multiple strains on the same day and allows predetermination of culture purity and challenge dose.

Details

Metrics

203 File views/ downloads
41 Record Views
Logo image