Production of anti-Cryptosporidium polyclonal antibodies and standardization of direct immunofluorescence for detecting oocysts in water.
BACKGROUND
The production of anti-Cryptosporidium polyclonal antibodies and its use in direct immunofluorescence assays to determine the presence of Cryptosporidium in water are described in the present work.


METHODS
Two rabbits were immunized with soluble and particulate antigens from purified Cryptosporidium oocysts. The sera produced were prepared for immunoglobulin G extraction, which were then purified and conjugated with fluorescein isothiocyanate (FITC). Slides containing known amounts of oocysts were prepared to determine the sensitivity of the technique. To test the specificity, slides containing Giardia duodenalis cysts were prepared.


RESULTS
The conjugate was successfully used in water samples experimentally contaminated with Cryptosporidium oocysts, and it was possible to detect up to five oocysts/spot, corresponding to contamination of 250 oocysts/mL.


CONCLUSIONS
The three immunizations performed in the rabbits were enough to produce antibodies against Cryptosporidium, the standard direct immunofluorescence assay permitted the detection of five oocysts in 20% of the samples, and no cross-reaction with Giardia duodenalis cysts occurred.
Universidade Federal do Paraná, Curitiba, PR, Brazil.
Silvia Cristina
SC
Osaki
Adriana Oliveira
AO
Costa
Ludmilla Della Coletta
LD
Troiano
Ernesto Renato
ER
Kruger
Juliana Tracz
JT
Pereira
Nelson Luis Mello
NL
Fernandes
Márcia Benedita de Oliveira
MB
Silva
Vanete Thomaz
VT
Soccol
D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis*; D003458:Cryptosporidium / Q000276:immunology* / Q000302:isolation & purification; D019085:Fluorescent Antibody Technique, Direct / Q000592:standards; D005618:Fresh Water / Q000469:parasitology*; D033661:Oocysts / Q000276:immunology; D011817:Rabbits; D012680:Sensitivity and Specificity
D000913:Antibodies, Protozoan