Characterisation of the immune repertoire of a humanised transgenic mouse through immunophenotyping and high-throughput sequencing
Curation statements for this article:-
Curated by eLife
eLife assessment
Humanized transgenic mice represent an important tool for antibody discovery and vaccine profiling but their similarity to human immune responses has not been established so far. In this manuscript, Richardson et al. comprehensively characterize IgH repertoires of Ky mice that carry human immunoglobulin heavy (IgH) and light chain (Igk and l) genes. The data presented here will be useful for setting a foundation for the use of this model, as well as other similar transgenic models, in future studies.
This article has been Reviewed by the following groups
Listed in
- Evaluated articles (eLife)
- Immunology and Inflammation (eLife)
Abstract
Immunoglobulin loci-transgenic animals are widely used in antibody discovery and increasingly in vaccine response modelling. In this study, we phenotypically characterised B-cell populations from the Intelliselect Transgenic mouse (Kymouse) demonstrating full B-cell development competence. Comparison of the naïve B-cell receptor (BCR) repertoires of Kymice BCRs, naïve human, and murine BCR repertoires revealed key differences in germline gene usage and junctional diversification. These differences result in Kymice having CDRH3 length and diversity intermediate between mice and humans. To compare the structural space explored by CDRH3s in each species’ repertoire, we used computational structure prediction to show that Kymouse naïve BCR repertoires are more human-like than mouse-like in their predicted distribution of CDRH3 shape. Our combined sequence and structural analysis indicates that the naïve Kymouse BCR repertoire is diverse with key similarities to human repertoires, while immunophenotyping confirms that selected naïve B cells are able to go through complete development.
Article activity feed
-
-
eLife assessment
Humanized transgenic mice represent an important tool for antibody discovery and vaccine profiling but their similarity to human immune responses has not been established so far. In this manuscript, Richardson et al. comprehensively characterize IgH repertoires of Ky mice that carry human immunoglobulin heavy (IgH) and light chain (Igk and l) genes. The data presented here will be useful for setting a foundation for the use of this model, as well as other similar transgenic models, in future studies.
-
Reviewer #1 (Public Review):
In this manuscript, Richardson et al. describe the repertoire characteristics of Ky mice that carry human immunoglobulin heavy (IgH) and light chain (Igk and l) genes. Immunophenotyping revealed no abnormalities in B cell subsets in the bone marrow, spleen, or lymph nodes of Ky mice (Fig. 1) and the light chain k/l ratio was similar to that observed in humans. Bulk RNA-seq showed some differences in VH, DH, and JH utilization in Ky mice compared to humans (Fig. 2). Ky sequences also had slightly shorter CDRH3 regions (Fig. 3) with a diversity index lying between that of mice and humans (Fig. 4). Use of a novel algorithm further substantiated similarities between Ky mice and human-derived sequences. The authors conclude that Ky mice are suitable to study human immune responses.
Richardson et al. have compiled …
Reviewer #1 (Public Review):
In this manuscript, Richardson et al. describe the repertoire characteristics of Ky mice that carry human immunoglobulin heavy (IgH) and light chain (Igk and l) genes. Immunophenotyping revealed no abnormalities in B cell subsets in the bone marrow, spleen, or lymph nodes of Ky mice (Fig. 1) and the light chain k/l ratio was similar to that observed in humans. Bulk RNA-seq showed some differences in VH, DH, and JH utilization in Ky mice compared to humans (Fig. 2). Ky sequences also had slightly shorter CDRH3 regions (Fig. 3) with a diversity index lying between that of mice and humans (Fig. 4). Use of a novel algorithm further substantiated similarities between Ky mice and human-derived sequences. The authors conclude that Ky mice are suitable to study human immune responses.
Richardson et al. have compiled a comprehensive dataset of Ig sequences from Ky mice to compare with human repertoires. The differences in gene segment utilization are potentially interesting but there is little discussion of the ramifications of these differences during immune responses. They briefly stated that previously published studies of immunizations in Ky mice support their conclusion that these mice respond like humans. However, no details were provided, and it is difficult to assess how similarly Ky mice respond to specific antigens compared to humans. Given the substantial amount of single-cell RNA-Seq data that is now available for responses against the SARS-CoV2 spike, this may be a good antigen to test in Ky mice. Finally, I defer to computational experts to speak to the novelty and validity of conclusions regarding diversity and structural variability in Ky mice compared to humans.
-
Reviewer #2 (Public Review):
Richardson et al. characterize through immunophenotyping and high-throughput sequencing humanized mice versus human repertoires using many different immunological/immune repertoire metrics. They find that overall, the naïve Kymouse BCR repertoire is diverse and similar to human repertoires.
Strengths
Overall the study is carefully designed and of broad interest.
- Detailed and established phenotypic and repertoire metrics are used to compare mice and human models.
- Rigorous statistical analysis is mostly used to establish similarity.
- Detailed description of the analyses performed.Weaknesses
- Improvements could be made in the analyses (at times not far-reaching enough), figures (not self-explanatory enough), and text (too verbose).
-
Reviewer #3 (Public Review):
The primary objectives of this manuscript were to characterize "the baseline phenotypic diversity in B cells and B cell receptors (BCRs) in the Kymouse" and draw comparisons to existing mouse and human datasets. Specifically, the authors place an emphasis on investigating whether the BCR repertoire has characteristics in common with repertoires from healthy humans (as expected), rather than wild-type mice (C57BL/6). In my opinion, the authors have met these basic objectives. The authors conclude that while the Kymouse repertoires have distinct heavy chain variables, diversity, and joining gene usage profiles and that their CDRH3 length is intermediate to the group averages of their control samples (C57BL/6, n=5; human, n-10), other important features, such as kappa and lambda light chain ratios, and CDRH3 …
Reviewer #3 (Public Review):
The primary objectives of this manuscript were to characterize "the baseline phenotypic diversity in B cells and B cell receptors (BCRs) in the Kymouse" and draw comparisons to existing mouse and human datasets. Specifically, the authors place an emphasis on investigating whether the BCR repertoire has characteristics in common with repertoires from healthy humans (as expected), rather than wild-type mice (C57BL/6). In my opinion, the authors have met these basic objectives. The authors conclude that while the Kymouse repertoires have distinct heavy chain variables, diversity, and joining gene usage profiles and that their CDRH3 length is intermediate to the group averages of their control samples (C57BL/6, n=5; human, n-10), other important features, such as kappa and lambda light chain ratios, and CDRH3 structures were more "human-like". The data presented here will be useful for setting a foundation for the use of this model in future studies (as well as other similar transgenic models). Ultimately, how the Kymouse model can be best utilized for different objectives will be important to determine. As outlined by the authors in the first paragraph of the introduction, whether the repertoires and associated immune responses mounted by these animals can be "considered representative of humans" will likely need additional demonstration through investigations under various experimental conditions.
-
