الفهرس 
REVIEW OF LITERATURE
DiagnosisOnly 14 pages are availabe for public view
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Abstract
The aim of the study is to improve the diagnosis of
babesiosis infected cattle in Egypt and analyzing the pattern of gene expression for a group of
cytokines in these cattle.
Blood samples were randomly collected from 296 apparently healthy cattle. Microscopic
examination, cELISA and nPCR were used for diagnosis of babesiosis infected cattle. Also, real-time
PCR was performed to evaluate the immune response of infected cattle through evaluation of IFN-γ,
IL-1β and TGF-β1 cytokine genes expression. The results of the microscopic examination for
babesiosis revealed that only 33 animals were infected with overall prevalence rate of 12%. cELISA
analysis showed that of 296 serum samples tested, 130 (44%) were positive for Babesia spp., 64
(21.6%) were positive for B. bigemina,
32 (10.8%) were positive for B. bovis and 34 (11.6%) were positive both spp. In the nPCR, 117
(39.5%) samples were positive for Babesia spp., 55 (18.6%) were positive for B. bigemina, 32
(10.8%) samples were positive for B. bovis and 30 (10.1%) were positive for mixed infection. The
present study results showed the high sensitivity of nPCR technique in detection of babesial
infection as compared to microscopic examination. Statistically, using Chi square
test, it was found that the differences between the three
methods were statistically significant.
Real-time PCR was carried out on 20 samples, positive for B. bovis; 20 samples, positive for both
species and 10 samples, positive for B.bigemina using cELISA and nPCR and 20 samples negative for
both spp. Real-time PCR results revealed that the animals with sub-clinical babesiosis had a
decrease in IFN-γ cytokine gene expression compared to the uninfected animals. IFN-γ mRNA
levels were significantly down-regulated by 18.1 fold (P<0.05) in B.bovis infected animals,
significantly down-regulated by 10.1 fold (P<0.01) in mixed (B.bovis and B.bigemina) infected
animals and significantly down- regulated by 11.9 fold (P<0.01) in B.bigemina infected animals
compared to the uninfected animals. On the other hand, it was found that animals with sub-clinical
babesiosis had an increase in TGF- β1 cytokine gene expression compared to the uninfected animals.
TGF- β1 mRNA levels were significantly up-regulated by 4.7 fold (P<0.01) in B.bovis infected
animals, significantly up-regulated by 7.1 fold (P<0.01) in mixed (B.bovis and B.bigemina) infected
animals and significantly up-regulated by 9.8 fold (P<0.05) in B.bigemina infected animals. These
results suggest that the down-regulation of IFN-γ gene expression noted in sub-
clinically infected animals may be a result of the shift from
Th1 type response to Treg type response (TGF-β1 gene). IL-1β mRNA levels were found to be
significantly up- regulated by 2.9 fold (P<0.05) in B.bovis infected animals, significantly
up-regulated by 3.4 fold (P<0.01) in mixed (B.bovis and B.bigemina) infected animals and
significantly up-regulated by 1.8 fold (P<0.05) in B.bigemina infected animals through the
sub-clinical phase of babesiosis compared to the uninfected animals.
In conclusion, the combination between cELISA and nPCR may offer the greatest sensitivity for
babesial diagnosis especially through the sub-clinical phase of infection. Also, the immune
response of Babesia infected cattle during the sub-clinical phase of the disease may be achieved
through the up-regulation of TGF-β1, a Treg cytokine and IL-1β that accompanied by the down-
regulation of IFN-γ, a Th1 cytokine.