Role of interleukin-12 in patients with dengue hemorrhagic fever.
Interleukin (IL)-12 has a broad range of activities including regulation of cytokine synthesis and selective promotion of Th1-type cell development. A shift from a Th1-type response to Th2-type has been suggested to be important in the pathogenesis of dengue hemorrhagic fever (DHF). This study was undertaken to investigate the possible role of IL-12 in this shift. A total of 76 patients with various grades of dengue illness and 21 normal healthy controls were tested for IL-12 levels in serum samples and IL-12 mRNA in their peripheral blood mononuclear cells. The results showed that the levels of IL-12 were the highest in patients with dengue fever (270+/-102 pg ml(-1)) followed by decreasing levels in the patients with DHF grade I (198+/-86 pg ml(-1); P<0.05) and DHF grade II (84+/-52 pg ml(-1); P<0.001). Neither IL-12 nor its mRNA could be detected in the patients with DHF grades III and IV. The cytokine appeared and reached peak levels during the first 4 days of illness, started to decline by day 5-8 and disappeared by day 9 onwards. The absence of IL-12 during severe illness and late phases of the disease may be responsible for the shift to a Th2-type response and thus for the pathogenesis of DHF.
Pacsa
A S
AS
Department of Microbiology, Faculty of Medicine, Kuwait University, P.O. Box 24923, Safat, Kuwait.
Agarwal
R
R
Elbishbishi
E A
EA
Chaturvedi
U C
UC
Nagar
R
R
Mustafa
A S
AS
D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D018664:Interleukin-12 / Q000097:blood* / Q000235:genetics; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D012333:RNA, Messenger / Q000032:analysis; D011933:Reagent Kits, Diagnostic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019595:Severe Dengue / Q000097:blood / Q000276:immunology*
D012333:RNA, Messenger; D011933:Reagent Kits, Diagnostic; D018664:Interleukin-12