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Designer antigens for elicitation of broadly neutralizing antibodies against HIV.

Kok T, Gaeguta A, Finnie J, Gorry PR, Churchill M, Li P - Clin Transl Immunology (2014)

Bottom Line: Using defined HIV prefusion DAGs, we have produced monoclonal antibodies (mAbs) specific to novel epitopes on HIV prefusion intermediates.These mAbs do not react with the static/native surface HIV or cellular antigens, but react with the DAGs.This is a paradigm shift from the current mainstream approach of screening elite patients' bNAbs.

View Article: PubMed Central - PubMed

Affiliation: School of Molecular and Biomedical Science, University of Adelaide , Adelaide, South Australia, Australia ; SA Pathology , Adelaide, South Australia, Australia.

ABSTRACT
Broadly neutralizing antibodies (bNAbs) are a consistent protective immune correlate in human immunodeficiency virus (HIV) patients as well as in passive immunotherapy studies. The inability to elicit bNAbs is the core reason underlining the repeated failures in traditional HIV vaccine research. Rare monoclonal bNAbs against HIV, however, have been produced. The significance of producing and studying more monoclonal bNAbs against HIV is underlined by its capability of defining critical epitopes for antigen designs aimed at the development of a serum-neutralizing HIV vaccine. In this regard, traditional antigen preparations have failed. There is a need to clearly advocate the concept, and systematic study, of more sophisticated 'designer antigens' (DAGs), which carry epitopes that can lead to the elicitation of bNAbs. Using an extremely efficient cell-to-cell HIV infection model for the preparation of HIV prefusion intermediates, we have investigated a novel and systematic approach to produce (not screen for) potential bNAbs against HIV. We have established the concept and the experimental system for producing formaldehyde-fixed HIV DAGs that carry temperature-arrested prefusion intermediates. These prefusion intermediates are structures on the cell surface after viral attachment and receptor engagement but before fully functional viral entry. Using defined HIV prefusion DAGs, we have produced monoclonal antibodies (mAbs) specific to novel epitopes on HIV prefusion intermediates. These mAbs do not react with the static/native surface HIV or cellular antigens, but react with the DAGs. This is a paradigm shift from the current mainstream approach of screening elite patients' bNAbs.

No MeSH data available.


Related in: MedlinePlus

(a) Confocal trifluorophore IF staining of DAG19 and H3B cells with 5E1 mAb, patient's HIV serum and anti-human CD4. (b) Confocal trifluorophore IF staining of DAG19 and H3B cells with 8B3 mAb, patient's HIV serum and anti-human CD4.
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fig5: (a) Confocal trifluorophore IF staining of DAG19 and H3B cells with 5E1 mAb, patient's HIV serum and anti-human CD4. (b) Confocal trifluorophore IF staining of DAG19 and H3B cells with 8B3 mAb, patient's HIV serum and anti-human CD4.

Mentions: The novel DAG specificity was further confirmed with confocal IF staining using HIV patient's serum, mouse mAb 5E1 and 8B3 and rat anti-human CD4. Figure 5a shows 5E1-specific staining (green) against DAG19 but not H3B cells—likely directed against novel, prefusion DAGs. The patient's serum showed specific fluorescence (blue) with DAG19 and H3B cells, which were virus positive. As expected, staining with rat anti-CD4 showed specific fluorescence (red) with the HuT78 cells (CD4+) but not against H3B cells, which are CD4 negative. Colocalized imaging showed blue, red and green fluorescence against the DAG19 cell but only reaction of patient's serum with HIV (blue) against H3B cells.


Designer antigens for elicitation of broadly neutralizing antibodies against HIV.

Kok T, Gaeguta A, Finnie J, Gorry PR, Churchill M, Li P - Clin Transl Immunology (2014)

(a) Confocal trifluorophore IF staining of DAG19 and H3B cells with 5E1 mAb, patient's HIV serum and anti-human CD4. (b) Confocal trifluorophore IF staining of DAG19 and H3B cells with 8B3 mAb, patient's HIV serum and anti-human CD4.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4232059&req=5

fig5: (a) Confocal trifluorophore IF staining of DAG19 and H3B cells with 5E1 mAb, patient's HIV serum and anti-human CD4. (b) Confocal trifluorophore IF staining of DAG19 and H3B cells with 8B3 mAb, patient's HIV serum and anti-human CD4.
Mentions: The novel DAG specificity was further confirmed with confocal IF staining using HIV patient's serum, mouse mAb 5E1 and 8B3 and rat anti-human CD4. Figure 5a shows 5E1-specific staining (green) against DAG19 but not H3B cells—likely directed against novel, prefusion DAGs. The patient's serum showed specific fluorescence (blue) with DAG19 and H3B cells, which were virus positive. As expected, staining with rat anti-CD4 showed specific fluorescence (red) with the HuT78 cells (CD4+) but not against H3B cells, which are CD4 negative. Colocalized imaging showed blue, red and green fluorescence against the DAG19 cell but only reaction of patient's serum with HIV (blue) against H3B cells.

Bottom Line: Using defined HIV prefusion DAGs, we have produced monoclonal antibodies (mAbs) specific to novel epitopes on HIV prefusion intermediates.These mAbs do not react with the static/native surface HIV or cellular antigens, but react with the DAGs.This is a paradigm shift from the current mainstream approach of screening elite patients' bNAbs.

View Article: PubMed Central - PubMed

Affiliation: School of Molecular and Biomedical Science, University of Adelaide , Adelaide, South Australia, Australia ; SA Pathology , Adelaide, South Australia, Australia.

ABSTRACT
Broadly neutralizing antibodies (bNAbs) are a consistent protective immune correlate in human immunodeficiency virus (HIV) patients as well as in passive immunotherapy studies. The inability to elicit bNAbs is the core reason underlining the repeated failures in traditional HIV vaccine research. Rare monoclonal bNAbs against HIV, however, have been produced. The significance of producing and studying more monoclonal bNAbs against HIV is underlined by its capability of defining critical epitopes for antigen designs aimed at the development of a serum-neutralizing HIV vaccine. In this regard, traditional antigen preparations have failed. There is a need to clearly advocate the concept, and systematic study, of more sophisticated 'designer antigens' (DAGs), which carry epitopes that can lead to the elicitation of bNAbs. Using an extremely efficient cell-to-cell HIV infection model for the preparation of HIV prefusion intermediates, we have investigated a novel and systematic approach to produce (not screen for) potential bNAbs against HIV. We have established the concept and the experimental system for producing formaldehyde-fixed HIV DAGs that carry temperature-arrested prefusion intermediates. These prefusion intermediates are structures on the cell surface after viral attachment and receptor engagement but before fully functional viral entry. Using defined HIV prefusion DAGs, we have produced monoclonal antibodies (mAbs) specific to novel epitopes on HIV prefusion intermediates. These mAbs do not react with the static/native surface HIV or cellular antigens, but react with the DAGs. This is a paradigm shift from the current mainstream approach of screening elite patients' bNAbs.

No MeSH data available.


Related in: MedlinePlus