Faculty Opinions recommendation of The Thomsen-Friedenreich antigen-binding lectin jacalin interacts with desmoglein-1 and abrogates the pathogenicity of pemphigus foliaceus autoantibodies in vivo.

The biophysical properties of therapeutic antibodies influence their manufacturability, efficacy, and safety. To develop an anti-cancer antibody, we previously generated a human monoclonal antibody (Ab417) that specifically binds to L1 cell adhesion molecule with a high affinity, and we validated its anti-tumor activity and mechanism of action in human cholangiocarcinoma xenograft models. In the present study, we aimed to improve the biophysical properties of Ab417. We designed 20 variants of Ab417 with reduced aggregation propensity, less potential post-translational modification (PTM) motifs, and the lowest predicted immunogenicity using computational methods. Next, we constructed these variants to analyze their expression levels and antigen-binding activities. One variant (Ab612)—which contains six substitutions for reduced surface hydrophobicity, removal of PTM, and change to the germline residue—exhibited an increased expression level and antigen-binding activity compared to Ab417. In further studies, compared to Ab417, Ab612 showed improved biophysical properties, including reduced aggregation propensity, increased stability, higher purification yield, lower pI, higher affinity, and greater in vivo anti-tumor efficacy. Additionally, we generated a highly productive and stable research cell bank (RCB) and scaled up the production process to 50 L, yielding 6.6 g/L of Ab612. The RCB will be used for preclinical development of Ab612.

Download Full-text

Immunological and In-Vivo Neurological Studies on a Benzoic Acid-Specific T-Cell-Derived Antigen-Binding Molecule from the Serum of a Toluene-Sensitive Patient

Archives of Environmental Health An International Journal ◽

10.1080/00039890009604022 ◽

2000 ◽

Vol 55 (5) ◽

pp. 304-318 ◽

Cited By ~ 7

Author(s):

Zeinab Khalil ◽

George M. Georgiou ◽

Henry Ogedegbe ◽

Robert E. Cone ◽

Faye Simpson ◽

...

Keyword(s):

T Cell ◽

Benzoic Acid ◽

Antigen Binding

Download Full-text

In Vivo Tumor Targeting of a Recombinant Single-Chain Antigen-Binding Protein

JNCI Journal of the National Cancer Institute ◽

10.1093/jnci/82.14.1191 ◽

1990 ◽

Vol 82 (14) ◽

pp. 1191-1197 ◽

Cited By ~ 203

Author(s):

D. Colcher ◽

R. Bird ◽

M. Roselli ◽

K. D. Hardman ◽

S. Johnson ◽

...

Keyword(s):

Tumor Targeting ◽

Binding Protein ◽

Antigen Binding ◽

Single Chain

Download Full-text

Induction of idiotype-bearing, nuclease-specific helper T cells by in vivo treatment with anti-idiotype.

Journal of Experimental Medicine ◽

10.1084/jem.154.1.24 ◽

1981 ◽

Vol 154 (1) ◽

pp. 24-34 ◽

Cited By ~ 18

Author(s):

G G Miller ◽

P I Nadler ◽

Y Asano ◽

R J Hodes ◽

D H Sachs

Keyword(s):

T Cells ◽

Network Theory ◽

Individual Cell ◽

Binding Activity ◽

Helper T Cells ◽

Antigen Binding ◽

Receptor Interactions ◽

Detectable Antigen

Treatment of BALB/c mice with purified pig anti-(BALB/c anti-nuclease) anti-idiotypic antibodies has been found to induce the appearance of idiotype-bearing immunoglobulins (Id') in the serum of these mice in the absence of detectable antigen binding activity. This phenomenon appeared to require T cells in the hosts because no Id' was detected in the serum of nude mice similarly treated. Furthermore, the spleens of BALB/c mice treated with anti-idiotype were found to contain helper T cells capable of providing help in an in vitro plaque-forming cell response to trinitrophenyl-nuclease equivalent to that provided by helper T cells from the spleens of nuclease-primed animals. Helper T cells from both anti-idiotype-treated and nuclease-treated animals were found to be antigen-specific and to be similarly susceptible to elimination by treatment with anti-idiotype plus complement. Therefore, treatment with both antigen and anti-idiotype appeared to prime similar populations of antigen-specific helper T cells, while having different effects on the induction of antibody. These findings are consistent with the network theory of receptor interactions in the immune response, and may provide a means for studying individual cell populations involved in such interactions.

Download Full-text

Molecular characterization of antibodies bearing Id-460. II. Molecular basis for Id-460 expression.

Journal of Experimental Medicine ◽

10.1084/jem.162.5.1494 ◽

1985 ◽

Vol 162 (5) ◽

pp. 1494-1511 ◽

Cited By ~ 11

Author(s):

E A Dzierzak ◽

P Brodeur ◽

T Marion ◽

C A Janeway ◽

A Bothwell

Keyword(s):

Molecular Basis ◽

Molecular Genetic ◽

Gene Segment ◽

Binding Specificity ◽

Antigen Binding ◽

Measurable Effect ◽

Variable Regions ◽

Genetic Level

Id-460+ immunoglobulins can be induced in vivo by immunization with dinitrophenyl (DNP) or P. pneumotropica and form two nonoverlapping groups of antibodies with respect to antigen binding specificity. In this study, using Id-460+ antibodies of differing antigen binding specificities, we compared on the molecular genetic level the five gene segment combinations (VH, DH, JH, VL, and JL) that encode the variable regions of these idiotype-positive immunoglobulins. The Id-460 determinant appears to be a conformational or combinatorial determinant encoded by VH460 and VK1 crosshybridizing genes. DH, JH, and JK gene segments appear to have no measurable effect upon expression of Id-460. Finally, antigen binding specificity does not appear to simply localize to any particular gene segment but may in part be the result of somatic mutation and/or VDJH junctional sequences, whose length correlates roughly with antigen binding specificity.

Download Full-text

Avidity, Potency, and Cross-Reactivity of Monoclonal Antibodies to Pneumococcal Capsular Polysaccharide Serotype 6B

Infection and Immunity ◽

10.1128/iai.69.1.336-344.2001 ◽

2001 ◽

Vol 69 (1) ◽

pp. 336-344 ◽

Cited By ~ 29

Author(s):

Yan Sun ◽

Young-il Hwang ◽

Moon H. Nahm

Keyword(s):

Monoclonal Antibodies ◽

Capsular Polysaccharide ◽

Enzyme Linked Immunosorbent Assay ◽

Antigen Binding ◽

Strongly Correlated ◽

Pneumococcal Infections ◽

The Cross ◽

Binding Titer

ABSTRACT Many pneumococcal capsular polysaccharides (PSs) are similar in structure, and a pneumococcal antibody often binds to all of the PSs with a similar structure. Yet, these cross-reactive antibodies may bind to the structurally related pneumococcal capsular PSs with an avidity too low to be effective. If memory B cells producing such weakly cross-reactive antibodies are elicited with pneumococcal conjugate vaccines, the memory cells for low-avidity antibodies could compromise the subsequent immune responses to the cross-reactive PS (original antigenic sin). To investigate these issues, we produced 14 hybridomas secreting monoclonal antibodies (MAbs) to the capsular PS ofStreptococcus pneumoniae serotype 6B by immunizing BALB/c mice with antigens containing 6B PS and studied their epitope, avidity, in vitro opsonizing capacity, in vivo protective capacity, and “antigen binding titer” by enzyme-linked immunosorbent assay (ELISA) of 6A and 6B capsular PSs. Six MAbs bound to the non-cross-reactive 6B-specific epitope, and seven MAbs bound to the cross-reactive epitope present in both 6A and 6B PSs One MAb (Hyp6BM6) revealed a novel epitope. This epitope was found on 6A PS in solution, but not on 6A PS adsorbed onto the plastic surface of the ELISA plates. The avidity of the MAb for 6A or 6B PS ranged from 7.8 × 106 M−1 to 4.1 × 1011M−1. No MAbs were weakly cross-reactive, since none of the cross-reactive MAbs showed any tendency toward having less avidity to 6A PS (the cross-reactive PS) than to 6B PS. Avidity influenced the results of several antibody assays. When all of the hybridomas were examined, avidity strongly correlated with the titer of a unit amount of MAb to bind antigen-coated ELISA plates (r = 0.91) or to opsonize pneumococci in vitro (r = −0.85). Because both assay results are avidity dependent, the ELISA and the opsonization assay results were strongly correlated (r= 0.91), regardless of avidity. Avidity also correlated with the potency of a MAb to passively protect mice against pneumococcal infections. When only the immunoglobulin G hybridomas were examined, little increase in opsonizing capacity and in vivo protective potency was observed above 109 M−1. Taken together, an ELISA measuring antigen binding titer may be an adequate measure of the protective immunity induced with pneumococcal vaccines, and the absence of a partially cross-reactive MAb suggests that antigenic sin may not be significant in responses to vaccines against the S. pneumoniae 6B serotype.

Download Full-text

An IL-2-grafted antibody immunotherapy with potent efficacy against metastatic cancer

Nature Communications ◽

10.1038/s41467-020-20220-1 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Dilara Sahin ◽

Natalia Arenas-Ramirez ◽

Matthias Rath ◽

Ufuk Karakus ◽

Monika Hümbelin ◽

...

Keyword(s):

Single Molecule ◽

First Generation ◽

Metastatic Cancer ◽

Interleukin 2 ◽

Antigen Binding ◽

Cancer Models ◽

Advanced Malignancies ◽

Antibody Immunotherapy ◽

Binding Groove

AbstractModified interleukin-2 (IL-2) formulations are being tested in cancer patients. However, IL-2 immunotherapy damages IL-2 receptor (IL-2R)-positive endothelial cells and stimulates IL-2Rα (CD25)-expressing lymphocytes that curtail anti-tumor responses. A first generation of IL-2Rβ (CD122)-biased IL-2s addressed some of these drawbacks. Here, we present a second-generation CD122-biased IL-2, developed by splitting and permanently grafting unmutated human IL-2 (hIL-2) to its antigen-binding groove on the anti-hIL-2 monoclonal antibody NARA1, thereby generating NARA1leukin. In comparison to hIL-2/NARA1 complexes, NARA1leukin shows a longer in vivo half-life, completely avoids association with CD25, and more potently stimulates CD8+ T and natural killer cells. These effects result in strong anti-tumor responses in various pre-clinical cancer models, whereby NARA1leukin consistently surpasses the efficacy of hIL-2/NARA1 complexes in controlling metastatic disease. Collectively, NARA1leukin is a CD122-biased single-molecule construct based on unmutated hIL-2 with potent efficacy against advanced malignancies.

Download Full-text