Last data update: Jun 11, 2024. (Total: 46992 publications since 2009)
Records 1-4 (of 4 Records) |
Query Trace: Vafai A [original query] |
---|
Development and evaluation of an M2-293FT cell-based flow cytometric assay for quantification of antibody response to native form of matrix protein 2 of influenza A viruses
Zhong W , He J , Tang X , Liu F , Lu X , Zeng H , Vafai A , Fu TM , Katz JM , Hancock K . J Immunol Methods 2011 369 115-24 Matrix protein 2 (M2) of influenza A viruses is an attractive target for the development of broadly cross-protective influenza vaccines and therapeutic antibodies. The available evidence suggests that antibodies reactive to the natural tetrameric form of M2 proteins, rather than those to synthetic peptides of M2 ectodomain (M2e), best correlate with M2-mediated immune protection. However, the current ability to quantify strain-specific and/or subtype-cross-reactive M2 antibodies against the natural form of M2 antigens from influenza A viruses of different host origin is limited. In the present study, we generated a panel of 293FT transfected cell lines stably expressing full-length tetrameric forms of M2 molecules from human, avian and the swine-origin 2009 pandemic H1N1 influenza A virus, respectively, and developed an M2-293FT cell line-based flow cytometric assay (M2-FCA). Side-by-side comparison of M2-FCA with a synthetic M2e peptide-based indirect ELISA (M2e-ELISA) reveals that M2-FCA is highly efficient in quantifying both M2e sequence-specific and cross-reactive antibodies to the native form of M2 antigens. In contrast, promiscuity was evident when specificity and cross-reactivity of anti-M2 antibodies were assessed by M2e-ELISA. These results demonstrate that M2-FCA represents a rapid, simple and sensitive method to quantitatively assess specificity and cross-reactivity of anti-M2 antibodies after infection or vaccination. |
Comparative analysis of direct fluorescence, zenon labeling, and quantum dot nanocrystal technology in immunofluorescence staining
Tang X , He J , Partin J , Vafai A . J Immunoassay Immunochem 2010 31 (3) 250-7 A comparative analysis was performed to determine the sensitivity and efficiency of three fluorescent labeling techniques, including direct fluorescent-antibody staining (FA), Zenon labeling, and quantum dot (QD) nanocrystal technology. Two varicella-zoster virus immunoglobin (Ig) G forms, mAb 4F9 and mAb g62, were selected for these studies. The results indicated that: (1) All three methods demonstrated similar brightness and photostability; (2) the time required to conjugate the antibody varied, with Zenon labeling being the quickest; and (3) the stability of each conjugated complex was different, with FITC/rhodamine-conjugated antibody being the most stable. |
Stability of varicella-zoster virus and herpes simplex virus IgG monoclonal antibodies
Hart J , Miller C , Tang X , Vafai A . J Immunoassay Immunochem 2009 30 (2) 180-5 The stability of 3 monoclonal antibodies was analyzed at various temperatures and freeze/thaw cycles. Two varicella-zoster virus (VZV) IgGs (mAb 4F9 and mAb g62) and 1 herpes simplex virus 1 (HSV-1 mAb 1D4) were selected for these studies. IgGs were either incubated at various temperatures (25 degrees C, 37 degrees C, 45 degrees C, and 60 degrees C) for different periods of time (0 to 9 weeks) or processed for several freeze/thaw cycles. The reactivities of mAbs 4F9 (IgG1), g62 (IgG1) and 1D4 (IgG2b) were tested by indirect immunofluorescence assay (IFA). The results indicated that: (1) all three mAbs were stable at 25 degrees C and 37 degrees C for 9 weeks; (2) although the reactivities of mAbs g62 and 1D4 were diminished after 5 weeks, mAb 4F9 was stable at 45 degrees C for 9 weeks; and (3) all 3 IgGs lost reactivity after overnight incubation at 60 degrees C. In addition, the results showed that the reactivity of mAbs 4F9, g62 and 1D4 was not diminished after 12 freeze/thaw cycles. |
Varicella-zoster virus subunit vaccine
Vafai A . Open Vaccine J 2009 2 (1) 17-27 Varicella-zoster virus (VZV) causes chickenpox (Varicella) in children and shingles (Zoster) in elderly and immunosuppressed individuals. An attenuated VZV vaccine has been approved for general immunization to prevent varicella and zoster in the United States. Although this vaccine provides a high degree of protection against virus infection, the virus becomes latent in dorsal root ganglia and will reactivate to produce zoster. Therefore, there is a need for developing additional VZV vaccines that are capable of eliciting immune response to the virus but will not establish viral latency. Our studies have been focused on the development of a truncated secretory VZV glycoprotein (VZVgE) subunit vaccine. The results from our studies have shown that the VZV subunit vaccine: (1) elicits the induction of neutralizing antibodies in animals as well as in humans; and (2) stimulates the induction of VZVgE-specific antibodies in VZV-seropositive human mononuclear cells. Such a VZV glycoprotein antigen, therefore, may have the potential to be used as a candidate VZV glycoprotein subunit vaccine for prevention of primary VZV infection (Varicella) or boosting immune response against VZV reactivation (Zoster) in adults, the elderly and immunosuppressed individuals. copyright Abbas Wafai; Licensee Bentham Open. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Jun 11, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure