Previous Article | Next Article ![]()
Infection and Immunity, September 1998, p. 4469-4473, Vol. 66, No. 9
Department of Veterinary Science and
Microbiology, University of Arizona, Tucson, Arizona 85721
Received 26 March 1998/Returned for modification 1 June
1998/Accepted 10 June 1998
Cryptosporidium parvum is an important diarrhea-causing
protozoan parasite of immunocompetent and immunocompromised hosts. Immunoglobulin A (IgA) has been implicated in resistance to mucosal infections with bacteria, viruses, and parasites, but little is known
about the role of IgA in the control of C. parvum
infection. We assessed the role of IgA during C. parvum infection in neonatal mice. IgA-secreting hybridomas were
developed by using Peyer's patch lymphocytes from BALB/c mice which
had been orally inoculated with viable C. parvum
oocysts. Six monoclonal antibodies (MAbs) were selected for further
study based on indirect immunofluorescence assay reactivity with
sporozoite and merozoite pellicles and the antigen (Ag) deposited on
glass substrate by gliding sporozoites. Each MAb was secreted in
dimeric form and recognized a 23-kDa sporozoite Ag in Western
immunoblots. The Ag recognized comigrated in sodium dodecyl
sulfate-polyacrylamide gel electrophoresis with P23, a previously
defined neutralization-sensitive zoite pellicle Ag. MAbs were evaluated
for prophylactic or therapeutic efficacy against C. parvum, singly and in combinations, in neonatal BALB/c mice. A
combination of two MAbs given prophylactically prior to and 12 h
following oocyst challenge reduced the number of intestinal parasites
scored histologically by 21.1% compared to the numbers in mice given
an isotype-matched control MAb (P < 0.01). Individual MAbs given therapeutically in nine doses over a 96-h period following oocyst challenge increased efficacy against C. parvum
infection. Four MAbs given therapeutically each reduced intestinal
infection 34.4 to 42.2% compared to isotype-matched control
MAb-treated mice (P < 0.05). One MAb reduced
infection 63.3 and 72.7% in replicate experiments compared to
isotype-matched control MAb-treated mice (P < 0.0001). We conclude that IgA MAbs directed to neutralization-sensitive P23 epitopes may have utility in passive immunization against murine
C. parvum infection.
0019-9567/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Role of Immunoglobulin A Monoclonal Antibodies
against P23 in Controlling Murine Cryptosporidium
parvum Infection
*
Corresponding author. Mailing address: Department of
Veterinary Science and Microbiology, Veterinary Science and
Microbiology Building, Room 202, University of Arizona, Tucson, AZ
85721. Phone: (520) 621-4880. Fax: (520) 621-6366. E-mail:
fje{at}u.arizona.edu.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»