J. McElven | Cornell University (original) (raw)

Papers by J. McElven

Research paper thumbnail of Primary sequence and molecular model of the variable region of a mouse monoclonal anti-Der p 1 antibody showing a similar epitope specificity as human IgE

Clinical <html_ent glyph="@amp;" ascii="&"/> Experimental Allergy, 1998

Background Der p 1, a major mite allergen, elicits IgE antibody responses in 80% of patients suff... more Background Der p 1, a major mite allergen, elicits IgE antibody responses in 80% of patients suffering from dust mite allergy. Given the potent IgE eliciting properties of Der p 1, there is considerable interest in studying the molecular architecture of the variable (Fv) region of IgE antibodies specific for this allergen. Objectives IgE is present in human serum at extremely low concentrations, and as such it is practically impossible to purify sufficient quantities for structural studies. We have therefore sought to sequence and model a representative murine monoclonal (MoAb) anti-Der p 1 antibody, as a surrogate human IgE. Methods The cDNA coding for the Fv region of an anti-Der p 1 MoAb (2C7), that mimics the binding of human IgE to Der p 1, was amplified by PCR, cloned and sequenced. The predicted amino acid sequences were then compared with a directory of human germline Vgene segments. Modelling of the Fv region of MoAb 2C7 was carried out using the extensive database of existing immunoglobulin structures in the Brookhaven PDB. Results The MoAb 2C7 heavy chain showed greater than 70% homology with three members of the V H 3 family, DP-35, DP-53 and DP-54. Similarly, the light chain showed greater than 70% homology with 11 V K sequences, including the V K II sequences DPK18, DPK19 and DPK28. A molecular model of the Fv region of MoAb 2C7 was generated and can be accessed from the EMBL databank. Conclusions Antibodies similar to MoAb 2C7 could be generated as part of the human repertoire. The availability of 3-dimensional model of MoAb 2C7, as a surrogate human IgE antibody, combined with further data on its epitope specificity, will facilitate studies into IgE antibody responses to Der p 1. Fig. 5. A molecular model of the Fv region of MoAb 2C7, showing a side view (left) and a top view (right). The heavy chain and the light chain are shown in blue and green, respectively, and the CDRs of the heavy chain and the light chain are shown in orange and red, respectively.

Research paper thumbnail of Characterisation of a mouse monoclonal anti-idiotype reactive with a V region sequence commonly used by human immunoglobulins

Molecular Pathology, 2000

A mouse monoclonal antibody (2C7/IgG2b kappa) has been described recently, which is directed agai... more A mouse monoclonal antibody (2C7/IgG2b kappa) has been described recently, which is directed against the major house dust mite allergen Der p 1, and whose epitope specificity is representative of a major component of the human IgE anti-Der p 1 response. To characterise an anti-idiotypic antibody (2G10/IgG1 kappa) raised against monoclonal antibody 2C7 as surrogate human IgE anti-Der p 1. The specificity of the anti-idiotype antibody 2G10 was determined by competitive inhibition experiments using human and mouse immunoglobulins of known VH gene families. The epitope recognised by monoclonal antibody 2G10 was located on the molecular model of the Fv (fragment variable) region of monoclonal antibody 2C7. The data suggest that monoclonal antibody 2G10 is directed against a crossreactive idiotype on human IgE that is shared by polyclonal IgG. Competitive inhibition studies against human immunoglobulins, representative of VH2, VH3, and VH4 gene families, showed that monoclonal antibody 2G10 is mostly likely to be directed against sequences encoded by either VH3 or VH4 genes. The fact that monoclonal antibody 2G10 binds to the humanized (complementarity determining region (CDR) grafted) CAMPATH-1H antibody, but not to the original rat CAMPATH-1 YTH34.5.6 antibody, indicates that it is directed against a framework region rather than the CDRs. Analysis of amino acids in the VH region for charge, hydrophobicity, and accessibility suggests that reactivity with monoclonal antibody 2G10 is defined by a hexapeptide spanning residues 74-79 within framework region 3. The anti-idiotype monoclonal antibody 2G10 could potentially be used as a probe for determining the contribution of the VH3 and VH4 gene segments to antigenic specificity.

Research paper thumbnail of Primary sequence and molecular model of the variable region of a mouse monoclonal anti-Der p 1 antibody showing a similar epitope specificity as human IgE

Clinical <html_ent glyph="@amp;" ascii="&"/> Experimental Allergy, 1998

Background Der p 1, a major mite allergen, elicits IgE antibody responses in 80% of patients suff... more Background Der p 1, a major mite allergen, elicits IgE antibody responses in 80% of patients suffering from dust mite allergy. Given the potent IgE eliciting properties of Der p 1, there is considerable interest in studying the molecular architecture of the variable (Fv) region of IgE antibodies specific for this allergen. Objectives IgE is present in human serum at extremely low concentrations, and as such it is practically impossible to purify sufficient quantities for structural studies. We have therefore sought to sequence and model a representative murine monoclonal (MoAb) anti-Der p 1 antibody, as a surrogate human IgE. Methods The cDNA coding for the Fv region of an anti-Der p 1 MoAb (2C7), that mimics the binding of human IgE to Der p 1, was amplified by PCR, cloned and sequenced. The predicted amino acid sequences were then compared with a directory of human germline Vgene segments. Modelling of the Fv region of MoAb 2C7 was carried out using the extensive database of existing immunoglobulin structures in the Brookhaven PDB. Results The MoAb 2C7 heavy chain showed greater than 70% homology with three members of the V H 3 family, DP-35, DP-53 and DP-54. Similarly, the light chain showed greater than 70% homology with 11 V K sequences, including the V K II sequences DPK18, DPK19 and DPK28. A molecular model of the Fv region of MoAb 2C7 was generated and can be accessed from the EMBL databank. Conclusions Antibodies similar to MoAb 2C7 could be generated as part of the human repertoire. The availability of 3-dimensional model of MoAb 2C7, as a surrogate human IgE antibody, combined with further data on its epitope specificity, will facilitate studies into IgE antibody responses to Der p 1. Fig. 5. A molecular model of the Fv region of MoAb 2C7, showing a side view (left) and a top view (right). The heavy chain and the light chain are shown in blue and green, respectively, and the CDRs of the heavy chain and the light chain are shown in orange and red, respectively.

Research paper thumbnail of Characterisation of a mouse monoclonal anti-idiotype reactive with a V region sequence commonly used by human immunoglobulins

Molecular Pathology, 2000

A mouse monoclonal antibody (2C7/IgG2b kappa) has been described recently, which is directed agai... more A mouse monoclonal antibody (2C7/IgG2b kappa) has been described recently, which is directed against the major house dust mite allergen Der p 1, and whose epitope specificity is representative of a major component of the human IgE anti-Der p 1 response. To characterise an anti-idiotypic antibody (2G10/IgG1 kappa) raised against monoclonal antibody 2C7 as surrogate human IgE anti-Der p 1. The specificity of the anti-idiotype antibody 2G10 was determined by competitive inhibition experiments using human and mouse immunoglobulins of known VH gene families. The epitope recognised by monoclonal antibody 2G10 was located on the molecular model of the Fv (fragment variable) region of monoclonal antibody 2C7. The data suggest that monoclonal antibody 2G10 is directed against a crossreactive idiotype on human IgE that is shared by polyclonal IgG. Competitive inhibition studies against human immunoglobulins, representative of VH2, VH3, and VH4 gene families, showed that monoclonal antibody 2G10 is mostly likely to be directed against sequences encoded by either VH3 or VH4 genes. The fact that monoclonal antibody 2G10 binds to the humanized (complementarity determining region (CDR) grafted) CAMPATH-1H antibody, but not to the original rat CAMPATH-1 YTH34.5.6 antibody, indicates that it is directed against a framework region rather than the CDRs. Analysis of amino acids in the VH region for charge, hydrophobicity, and accessibility suggests that reactivity with monoclonal antibody 2G10 is defined by a hexapeptide spanning residues 74-79 within framework region 3. The anti-idiotype monoclonal antibody 2G10 could potentially be used as a probe for determining the contribution of the VH3 and VH4 gene segments to antigenic specificity.