title: Higher levels of dengue-virus-specific IgG and IgA during pre-defervescence associated with primary dengue hemorrhagic fever.
abstract: Dengue hemorrhagic fever (DHF), although predominantly associated with secondary infections, has also been reported in primary infections. An enhanced immune response including antibodies and cytokines is implicated in the pathogenesis of secondary DHF. However, the factors operating in primary DHF are poorly understood. To understand the role of the antibody response, the relative levels of different antibody isotypes during the acute phase of infection in primary and secondary dengue infections were determined. Levels of DENV-specific IgM, IgG, IgA and IgE were measured in the serum samples of 200 dengue patients and 20 dengue-naïve individuals. Samples were collected within 15 days of onset of illness. The DENV-specific IgM levels were significantly higher in DF cases compared to DHF, which was more evident in secondary infections and in post-defervescence samples. The levels of IgG, IgA and IgE were higher in DHF cases, with greater significance in primary infections. A higher level of IgG in DHF cases was evident in pre-defervescence samples, whilst the IgE level was higher in pre- and post-defervescence samples. There was a significant correlation of IgG titres with platelet counts, with higher titres associated with lower platelet counts. It is speculated that IgG, IgA and IgE produced in response to primary infections may contribute to pathogenesis, whilst IgM produced in response to secondary infections may protect against progression to severe disease.
authors.affiliation: Dengue Group, National Institute of Virology, 20-A Dr. Ambedkar Road, Pune, 411001, India.
authors.forename: Rupali
authors.initials: R
authors.lastname: Bachal
authors.affiliation: Dengue Group, National Institute of Virology, 20-A Dr. Ambedkar Road, Pune, 411001, India.
authors.forename: Kalichamy
authors.initials: K
authors.lastname: Alagarasu
authors.affiliation: Dengue Group, National Institute of Virology, 20-A Dr. Ambedkar Road, Pune, 411001, India.
authors.forename: Anand
authors.initials: A
authors.lastname: Singh
authors.affiliation: Dengue Group, National Institute of Virology, 20-A Dr. Ambedkar Road, Pune, 411001, India.
authors.forename: Asha
authors.initials: A
authors.lastname: Salunke
authors.affiliation: Dengue Group, National Institute of Virology, 20-A Dr. Ambedkar Road, Pune, 411001, India.
authors.forename: Paresh
authors.initials: P
authors.lastname: Shah
authors.affiliation: Dengue Group, National Institute of Virology, 20-A Dr. Ambedkar Road, Pune, 411001, India. cecilia.dayaraj@gmail.com.
authors.forename: Dayaraj
authors.initials: D
authors.lastname: Cecilia
mesh_terms: D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D003716:Dengue Virus / Q000276:immunology* / Q000502:physiology; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D008875:Middle Aged; D019595:Severe Dengue / Q000097:blood* / Q000175:diagnosis / Q000821:virology; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M