Abstract
The four serotypes of dengue virus (DENV) cause dengue fever (DF) and dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Severe disease has been associated with heterotypic secondary DENV infection, mediated by cross-reactive antibodies (Abs) and/or cross-reactive T cells. The role of cross-reactive immunity in mediating enhanced disease versus cross-protection against secondary heterotypic DENV infection is not well defined. A better understanding of the cross-reactive immune response in natural infections is critical for development of safe and effective tetravalent vaccines. We studied the B cell phenotype of circulating B cells in the blood of pediatric patients suspected of dengue during the 2010–2011 dengue season in Managua, Nicaragua (n = 216), which was dominated by the DENV-3 serotype. We found a markedly larger percentage of plasmablast/plasma cells (PB/PCs) circulating in DENV-positive patients as compared to patients with Other Febrile Illnesses (OFIs). The percentage of DENV-specific PB/PCs against DENV-3 represented 10% of the circulating antibody-producing cells (ASCs) in secondary DENV-3 infections. Importantly, the cross-reactive DENV-specific B cell response was higher against a heterotypic serotype, with 46% of circulating PB/PCs specific to DENV-2 and 10% specific to DENV-3 during acute infection. We also observed a higher cross-reactive DENV-specific IgG serum avidity directed against DENV-2 as compared to DENV-3 during acute infection. The neutralization capacity of the serum was broadly cross-reactive against the four DENV serotypes both during the acute phase and at 3 months post-onset of symptoms. Overall, the cross-reactive B cell immune response dominates during secondary DENV infections in humans. These results reflect our recent findings in a mouse model of DENV cross-protection. In addition, this study enabled the development of increased technical and research capacity of Nicaraguan scientists and the implementation of several new immunological assays in the field.
Highlights
Dengue is the most prevalent mosquito-borne viral disease affecting humans worldwide, mainly encountered in tropical and sub-tropical regions in peri-urban and urban areas, with almost half of the world’s population at risk for infection
In a number of cases, the disease can be more severe and sometimes fatal, with signs of bleeding and vascular leakage leading to shock (Dengue Hemorrhagic Fever/Dengue Shock Syndrome)
Severe disease has been associated with secondary sequential dengue virus (DENV) infections, i.e., infection with a second DENV serotype different from the serotype causing the first infection
Summary
Dengue is the most prevalent mosquito-borne viral disease affecting humans worldwide, mainly encountered in tropical and sub-tropical regions in peri-urban and urban areas, with almost half of the world’s population at risk for infection. DENV infection can be asymptomatic or can cause a spectrum of disease, which spans from classical dengue (DF) to more severe forms termed dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) [1]. DHF is characterized by hemorrhagic manifestations, platelet count #100,000 cells/mL; and signs of plasma leakage that may include elevated hematocrit, pleural effusion, ascites, edema, hypoproteinemia and/or hypoalbuminemia. The WHO developed a new classification of dengue disease that replaces the traditional classification and includes Dengue with or without Warning Signs and Severe Dengue [3]. This new classification has proven to be useful in clinical management of DENV-infected individuals; it may be less well-suited for pathogenesis studies [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
