Open AccessCytotoxic factor‐autoantibodies: possible role in the pathogenesis of dengue haemorrhagic fever
Author(s) -
Chaturvedi U.C.,
Elbishbishi E.A.,
Agarwal R.,
Mustafa A.S.
Publication year - 2001
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2001.tb01568.x
Subject(s) - dengue fever , pathogenesis , autoantibody , immunology , biology , virology , cytotoxic t cell , dengue virus , dengue haemorrhagic fever , antibody , genetics , in vitro
During dengue virus infection a unique cytokine, cytotoxic factor (hCF), is produced that is pathogenesis‐related and plays a key role in the development of dengue haemorrhagic fever (DHF). However, what regulates the adverse effects of hCF is not known. We have previously shown that anti‐hCF antibodies raised in mice, neutralise the pathogenic effects of hCF. In this study we have investigated the presence and levels of hCF‐autoantibodies in sera of patients with various severity of dengue illness ( n =136 ) and normal healthy controls ( n =50 ). The highest levels of hCF‐autoantibodies (mean±S.D.=36±20 U ml −1 ) were seen in patients with mild illness, the dengue fever (DF), and 48 out of 50 (96%) of the sera were positive. On the other hand the hCF‐autoantibody levels declined sharply with the development of DHF and the levels were lowest in patients with DHF grade IV (mean±S.D.=5±2 U ml −1 ; P =<0.001 as compared to DF). Only one of the 13 DHF grade IV patients had an antibody level above the ‘cut‐off’ value (mean plus 3 S.D. of the control sera). The analysis of data with respect to different days of illness further showed that the highest levels of hCF‐autoantibodies were present in DF patients at >9 days of illness. Moreover, the DF patients at all time points, i.e. 1–4, 5–8 and >9 days of illness had significantly higher levels of hCF‐autoantibodies ( P <0.001 ) than patients with DHF grade I, II, III and IV. In addition DHF grade I and grade II patients had significantly more positive specimens than DHF grade III and grade IV patients at all time points. These results suggest that elevated levels of hCF‐autoantibodies protect the patients against the development of severe forms of DHF and, therefore, it may be useful as a prognostic indicator.