Detection of R. felis and R. typhi in fleas using monoclonal antibodies

Rong Fang, P. E. Fournier, L. Houhamdi, A. F. Azad, Didier Raoult

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Rickettsia typhi and R. felis are flea-transmitted human pathogenic rickettsial species. To investigate the distributional dynamics of these rickettsiae we designed a micro-immunofluorescence assay (MIF) using species-specific monoclonal antibodies (MAbs) applied to flea cryosections. Our assay was performed in less than 3 h and its applicability was demonstrated by the detection of R. typhi in 50 artificially infected human body lice but in none of 50 uninfected lice. With MIF, we identified 31 positive among 32 fleas proven with PCR to be naturally infected with R. felis; and 7 positive among 32 fleas proven with PCR to be naturally infected with R. typhi. No cross-detection was observed with both MAbs. Fresh R. felis-infected fleas were significantly more MIF-positive than long conserved R. typhi-infected fleas (31/32 vs. 7/32, P < 0.01). This discrepancy may be linked to degradation of antigens by long-term freezing. For R. typhi-infected fleas, our assay was significantly more efficient when applied to fleas in early stages of infection (less than 15 days) by comparison with fleas frozen more than 20 days after infection (7/15 vs. 0/17, P = 0.01). This difference may be related to an antigenic modification caused by selection pressure in the vector and host process. The sensitivity of the described method did not exceed 47% (7/15) for R. typhi but, in contrast, was 97% for R. felis. Thus, our method appears to be useful for surveillance in R. felis infections, but requires further studies for the detection of R. typhi.

Original languageEnglish (US)
Pages (from-to)213-220
Number of pages8
JournalAnnals of the New York Academy of Sciences
Volume990
StatePublished - 2003
Externally publishedYes

Fingerprint

Felis
Siphonaptera
Rickettsia typhi
Assays
Monoclonal Antibodies
Fluorescent Antibody Technique
Freezing
Infection
Pediculus
Phthiraptera
Rickettsia
Polymerase Chain Reaction
Antigens
Degradation
Human Body

Keywords

  • Fleas
  • Immunofluorescence assay
  • Lice
  • Monoclonal antibodies
  • R. felis
  • R. typhi

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

Fang, R., Fournier, P. E., Houhamdi, L., Azad, A. F., & Raoult, D. (2003). Detection of R. felis and R. typhi in fleas using monoclonal antibodies. Annals of the New York Academy of Sciences, 990, 213-220.

Detection of R. felis and R. typhi in fleas using monoclonal antibodies. / Fang, Rong; Fournier, P. E.; Houhamdi, L.; Azad, A. F.; Raoult, Didier.

In: Annals of the New York Academy of Sciences, Vol. 990, 2003, p. 213-220.

Research output: Contribution to journalArticle

Fang, R, Fournier, PE, Houhamdi, L, Azad, AF & Raoult, D 2003, 'Detection of R. felis and R. typhi in fleas using monoclonal antibodies', Annals of the New York Academy of Sciences, vol. 990, pp. 213-220.
Fang, Rong ; Fournier, P. E. ; Houhamdi, L. ; Azad, A. F. ; Raoult, Didier. / Detection of R. felis and R. typhi in fleas using monoclonal antibodies. In: Annals of the New York Academy of Sciences. 2003 ; Vol. 990. pp. 213-220.
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