Jennifer VanAntwerp | Calvin College (original) (raw)

Women and Engineering by Jennifer VanAntwerp

Cambridge Scholars Publishing, 2022

Times have changed, but have they changed enough? And are they changing in the right direction? T... more Times have changed, but have they changed enough? And are they changing in the right direction? To answer these questions, we explore the changing face of sexual harassment among engineers both at work and in school. While the #MeToo movement has led to reductions in egregious sexual misconduct in the workplace like quid pro quo (sexual coercion), sexual assault, and unwanted sexual attention, backlash from the #MeToo movement and shifts in attitudes toward women that have emerged from the Trump era are offsetting many of these gains. Given the stubborn and persistent nature of both numerical and normative male dominance in many engineering fields as well as many of the unique characteristics of engineers and engineering, sexual harassment may be particularly difficult to address, reduce, and ultimately eliminate. The good news is that there are many tools in the toolbox for addressing the problem. This book offers a comprehensive examination of what the sexual harassment landscape presently looks like in engineering as well as how recent events, allegations, and presidential leadership have affected that landscape. Most importantly, it explores solutions that have the most promise for not only reducing harassment in engineering but building a strong, civil, and empathic foundation that can sustain such improvements. 7. Sexual Harassment during COVID-19 Harassment during remote work Harassment in the field Aggravating factors Harassment at the university Outcomes of sexual harassment Race and ethnicity Gender Conclusions 8. The Impact of Presidential Leadership Barack Obama, 44 th President of the U.S. Donald J. Trump, 45 th President of the U.S. Joseph R. Biden, 46 th President of the U.S. Conclusions iii 9. The Impact of Recent Social Movements The 2017 Women's March The #MeToo movement From awareness to action #MeTooSTEM Black Lives Matter Conclusions 179 10. Recent Allegations Governor Andrew Cuomo Blizzard (Activision) Conclusions 11. Solutions Learn, transfer, apply Sexual harassment training Civility and civility training Empathy and empathy training Bystander intervention and bystander training Reporting policies Coworker Solidarity Employee activism Conclusions 12. The Future Rewriting the story of unwanted sexual attention Rewriting the story of pervasive toxic culture Rewriting the story of sexist gender harassment Rewriting the story of sexual gender harassment Final thoughts

SAGE Open, 2021

Unmet or thwarted belonging needs have been implicated in multiple studies of women in engineerin... more Unmet or thwarted belonging needs have been implicated in multiple studies of women in engineering in college and in the engineering workforce. A wide range of other challenges that women face in engineering are tightly linked to deficits in belonging. Furthermore, many women face intersectional factors across race and ethnicity that make it even more difficult to belong. This literature review looks at women's struggles in engineering in the context of the fundamental psychological need to belong. Studies that investigate belonging are reviewed, as are major contributors to unmet or thwarted belonging including gender identity threat and normative and numerical male dominance. Belonging is not the only psychological need that is inadequately met for women in engineering, but it is a common factor in multiple contexts and the situation worsens as women progress in their career pathways. Studies of belonging among women in engineering underscore the importance of supporting women in fulfilling this basic need even when the cultural transformation of engineering into a gender-balanced environment is not yet a reality.

2019 ASEE Annual Conference & Exposition Proceedings

Based on studies of engineering students, it is recognized that engineering students who pursue e... more Based on studies of engineering students, it is recognized that engineering students who pursue engineering due to altruistic intent or intrinsic interest in engineering are more likely to persist to graduation. We sought to identify similar factors that promote persistence for women in the engineering workplace. Since we know that women leave the engineering workforce more frequently than men, identifying these factors is as important to retaining women in the engineering workplace as previous work to identify similar elements in the undergraduate years. The retention studies of women in the engineering workforce have largely focused on the structural features of the workplace, rather than on the women, themselves, who are making the decisions to stay or leave. While examining the workplace is important, identifying factors related specifically to the women is also an important and essential step to modifying or supplementing workplace culture to retain women in engineering for longer periods of time.

We hypothesized that women who strongly self-identified as engineers would be more likely to persist in the engineering workforce and those who did not would be more likely to leave the workforce. If we knew that strong engineering identities would lead to higher workforce
retention, then educators could employ interventions to intentionally develop this identity in their students before graduation. To assess the validity of this hypothesis, we conducted semi-structured interviews (similar to psychology’s Identity Status Interview) of 33 women with engineering degrees, including those who persisted in the engineering workforce and those who did not. We preceded the interviews with Likert scale measures of identity taken from the engineering education literature. We conducted theme-based coding of the interview transcripts for the workplace issues known to impede persistence and for engineering identity. Further, we took a grounded theory approach
for other factors that might appear in the data. Finally, we sought to determine the women’s reasons for staying or leaving the engineering workforce.

Our findings revealed that strong engineering identification does generally correspond to increased persistence, while a weaker identification corresponds to increased consideration of leaving engineering. We did find, though, that some non-persisters had a strong engineering identification and some persisters had a weaker engineering identity. Thus, other factors were influencing the validity of our hypothesis. The most prominent unexpected factor was that some women were pulled by a strong desire to pursue a vocation or passion that conflicted with engineering workplace persistence, such as teaching in K-12 or staying home with her children. We have named this phenomenon a competing vocation. Two other influencing factors arose to a lesser extent: persistence was sometimes affected by the degree to which the workplace met the women’s a) need for relatedness and b) expectations for employees being encouraged to help one another and/or the end customers (prosocial motivation). Thus, we found engineering identity to be an influential factor in the workplace persistence of degreed women engineers, followed by the level of workplace relatedness and opportunities to serve others within the workplace. Each of these findings has potential implications for engineering educators.

Proceedings of the American Society for Engineering Education Annual Conference, Jun 2015

Retention of the engineering workforce is of national importance for global competitiveness. Rete... more Retention of the engineering workforce is of national importance for global competitiveness. Retention of women engineers is of particular interest because of the impact of their lower starting representation and higher attrition rate on workforce diversity. Exit rates from engineering careers are highest in the first 10 years after graduation. Thus, unlike most workforce retention research, this study focuses on participants who are still in the midst of this critical phase of their careers. We investigated what engineering graduates say about how and why they make early career pathway choices. The motivations for their choices were examined through the lens of gender differences (and similarities) while resting on the fundamental psychological framework provided by self-determination theory (SDT). SDT has demonstrated that the more behaviors are autonomously motivated, the more stable, the more fulfilling, and the more persistent those behaviors become. The current qualitative study is based on interviews with twenty-two early-career engineering graduates (eleven men and eleven women) from three geographically and culturally distinct institutions. While a majority of both men and women expressed autonomous motivations, the ways in which they were expressed imply different outcomes for career persistence. While the results presented herein do not have statistical significance because of small sample size and qualitative methodology, they do provide insight into the types of patterns that emerge from men and women in terms of how they view their careers from past, present, and future perspectives. Understanding these patterns will be helpful in identifying them among early career graduates in engineering and taking appropriate steps to support continued persistence in the field. Identification of these patterns is also helpful for designing a quantitative study that can point to the significance of gender differences in a larger population.

Journal of Women and Minorities in Science and Engineering

This study presents persistent themes from interviewing twenty women (and a control group of eigh... more This study presents persistent themes from interviewing twenty women (and a control group of eight men) from three different types of universities who graduated in engineering and are at least three years past their engineering degree. Over 40% of women interviewed consistently report that in an ideal world, they would not persist in engineering; moreover, whether they choose to persist or not, an overwhelming majority report that their ideal job would involve serving people in society (70%) or the environment (15%). These ideals are inconsistent with existing opportunities in the corporate workplace but are consistent with ideals expressed in pre-engineering women from middle school to sophomore level.

Compared with men, the absence of opportunities to directly serve people or environment may well pose a barrier to long-term persistence for women in the engineering workplace. Combined with other barriers, including competing vocations related to marriage, raising children, and other interests outside of engineering, lack of opportunities to serve are an important part of what makes it difficult for women to turn their engineering degrees into long term, fulfilling, and productive careers. Indeed, the desire to serve society or
individuals in society remains a dominant career motivation for women, from middle school through retirement.

Protein Engineering by Jennifer VanAntwerp

Yeast surface display is a eucaryotic system for the directed evolution of protein binding and st... more Yeast surface display is a eucaryotic system for the directed evolution of protein binding and stability. For antibody affinity maturation, achievable single-pass enrichment factors are a critical variable. Both reliable recovery of rare clones (yield) and effective differentiation between clones of only slightly improved affinity (purity) are paramount. To validate yeast display’s purification potential, trial sorting experiments were performed. The D1.3 (anti-hen egg lysozyme) single chain variable fragment antibody and a 2-fold higher affinity mutant (M3) were each displayed on the surface of Saccharomyces cerevisiae. M3-displaying cells were mixed into the D1.3-displaying cells at a ratio of 1:1000. Cells were fluorescently labeled according to antigen equilibrium binding and then sorted using a flow cytometer. Single-pass enrichment of M3-displaying cells was 125-fold (( 65-fold). This level of performance is achievable
because of the precision and reproducibility of optimal labeling conditions. This work further demonstrates the capability of yeast display for very fine discrimination between mutant clones of similar affinity. Because large improvements in affinity typically result from combinations of small changes, this capability to identify subtle improvements is essential for rapid affinity maturation.

Printout. Thesis (Ph. D.)--University of Illinois at Urbana-Champaign, 1999. Vita. Includes bibli... more Printout. Thesis (Ph. D.)--University of Illinois at Urbana-Champaign, 1999. Vita. Includes bibliographical references (leaves 152-161).

Methodological advances and new applications have fueled significant growth in the practice of po... more Methodological advances and new applications have fueled significant growth in the practice of polypeptide library screening. Review.

Understanding the structural and dynamic determinants of binding free energy in the antigen-antib... more Understanding the structural and dynamic determinants of binding free energy in the antigen-antibody bond is of great interest. Much work has focused on selective mutations in order to locate key interaction residues, but this generally results in reduced affinity. The present work instead examines a higher-affinity mutant to characterize the thermodynamic pathway of the affinity maturation process. We have compared the antigen binding energetics of scFv D1.3, an anti-hen egg lysozyme single chain antibody, with a higheraffinity mutant (Hawkins, R. E., Russell, S. J., Baier, M. and Winter, G. . The mutant has fivefold higher affinity for lysozyme but nearly the same enthalpy and heat capacity change upon binding, as measured by isothermal titration calorimetry. Thus, much of the binding free energy difference can be attributed to entropic effects. Fluorescence quenching with acrylamide indicates that this more favorable entropy change may result from a more flexible mutant-lysozyme complex and thus be a configurational entropy effect.

Engineering Education by Jennifer VanAntwerp

Retention of engineering students is a much-studied subject. The bulk of existing literature focu... more Retention of engineering students is a much-studied subject. The bulk of existing literature focuses on students in large, Research-I institutions – arguably schools sharing a common context or educational dynamic. Current instruments available to study retention have not focused on how motivations, interests, and individual backgrounds (psychosocial and personal attributes) may vary with educational context (institutional attributes) and, as a result, may very well miss aspects of a student’s learning experience that could be particularly important to retention. Studies from both engineering education and social sciences such as educational psychology fail to fully examine how the educational environment interacts with personal experiences and attributes among engineering students to influence retention among all students; of particular interest is retention of females, since this population of engineering students has consistently reflected higher attrition from the field of study. The role of context in the development of instruments for retention studies needs to be studied more thoroughly.

For this work, we are developing a new survey instrument to explore the effects of context on engineering retention; this article describes the pilot test of the instrument. Seven factors related to retention, as reported in engineering education, science education, and educational psychology literature, were identified as relevant to measuring educational context and therefore selected for study:

Cultural influences, including family and friends
Recruitment activities to engineering, as experienced before entering college
Participation in engineering-related activities
Self-perception and self-efficacy
Motivations for studying engineering
Definitions of success, personally and academically
Perceptions of the learning environment.

For each factor, a set of Likert scale survey stems was developed. In addition, demographic data were included. The stems were reviewed by an expert panel in accordance with best practice in the field of educational psychology, and the resulting instrument was pilot-tested with 224 engineering undergraduates. Confirmatory Factor Analysis (CFA) was used for validation purposes.

Future work will involve quantitative-analysis-driven modification of the instrument, followed by administration at multiple institutions with varying contexts and comparisons to further explore the role of context in engineering retention. We will add a qualitative research component to enrich our understanding of the role of context in student decision-making associated with undergraduate engineering program retention.

The stated mission of many Christian undergraduate engineering schools involves producing enginee... more The stated mission of many Christian undergraduate engineering schools involves producing engineering graduates who have a distinct orientation towards serving others with their technological knowledge. This other-orientedness is a distinguishing element of the consensus definition of calling in published literature to date. In the present work, persons 5 to 30 years post-graduation from engineering colleges were studied to examine the role that calling as defined by other-orientedness plays in various career decisions they had made. A brief on-line survey was administered to over 600 respondents who had earned an engineering degree, in order to collect information on demographics, attitudes toward engineering and work, religious faith commitment, and willingness to participate in a follow-up interview. Approximately 70 people agreed to participate in a 60-to-90 minute, semi-structured interview. This subset was used to select participants for this study. Participants were purposefully selected based on creating a wide distribution of graduation years, gender, and alma mater (14 Christian college alumni and 9 alumni of a public, secular institution). Twenty three interviews were conducted. Interview questions were designed to elicit the role of faith in career-related decision-making, as well as to reveal the presence of a sense of calling, either to engineering or to other life roles. Interviews were analyzed using a constant comparative method of analysis to identify common themes. Results indicate that graduates of Christian colleges did not differ noticeably from persons graduating from secular institutions in their initial reasons for choosing engineering. They also did not differ noticeably in their expression of a sense of calling (expressed as other-orientedness). Only about half of Christian college engineering alumni expressed an orientation towards service to others as a part of their engineering work. In order to better align with Christian college mission statements, faculty and engineering departments at such institutions are encouraged to seek ways to assist engineering students to be better prepared for recognizing and seeking out the other-oriented, service aspects of a professional career in engineering. Methods Research Questions This study was guided by the following research questions:

In the past 5 years, research has emerged to clearly show that girls at the beginning of the engi... more In the past 5 years, research has emerged to clearly show that girls at the beginning of the engineering pipeline do not enter engineering because they prefer professions that they feel have more potential to change society. They simply want jobs that make a difference in the world by positively influencing poverty, health care, the environment, and other social problems. The other side of the pipeline is in industry, alongside of women who have been working in engineering for some time after graduation. Understanding the experiences of these women from the perspective of having successfully completed at least one engineering degree is important to understanding both how to enhance long-term persistence and how to better recruit and retain girls who are rejecting engineering early in the pipeline. This study presents persistent themes from interviewing over 40 women from three different types of universities who graduated in engineering and are at least 5 years past their engineerin...

2004 Annual Conference Proceedings

A novel first-year course (Engineering Chemistry and Materials Science) was created to broaden th... more A novel first-year course (Engineering Chemistry and Materials Science) was created to broaden the technical foundation in the BSE program at Calvin College. The content of the new course was drawn from two established courses -an engineering course in materials science (which was subsequently eliminated) and the second semester of first-year chemistry (which most engineering students did not previously take). In an innovative format, the course is team-taught by faculty from the engineering and chemistry departments. The material is integrated, so that the chemistry is motivated by relation to engineering properties, while the materials science is more thoroughly grounded in scientific principles. This allows greater conceptual depth for the materials science than was present in the previous stand-alone course. It also provides all engineering students with a greater chemistry background, and makes the chemistry seem more relevant and interesting. A weekly lab illustrates concepts, attracts the attention of hands-on learners, and is also integrative. For example, in one lab period students synthesize several polymers. The next lab period, they test various material properties of those polymers, relating these observations back to the structures they now know well. The course material is technical and challenging. Students enjoy the challenge, whereas the course previously taken by secondsemester freshmen bored many students because they found it too simple, and repetitive of the first-semester freshman design course. The new interdisciplinary course has been successful in two years of being taught. Students particularly appreciate the lab, saying it makes the lecture more interesting, relevant, and easier to understand. Faculty see more student engagement with the material. Initial data indicate significant improvement in first-year-to-sophomore year retention rates.

Christian Education in Engineering by Jennifer VanAntwerp

A brief on-line survey was administered to over 600 respondents who had earned an engineering degree, in order to collect information on demographics, attitudes toward engineering and work, religious faith commitment, and willingness to participate in a follow-up interview. Approximately 70 people agreed to participate in a 60-to-90 minute, semi-structured interview. This sub-set was used to select participants for this study. Participants were purposefully selected based on creating a wide distribution of graduation years, gender, and alma mater (14 Christian college alumni and 9 alumni of a public, secular institution). Twenty three interviews were conducted. Interview questions were designed to elicit the role of faith in career-related decision-making, as well as to reveal the presence of a sense of calling, either to engineering or to other life roles. Interviews were analyzed using a constant comparative method of analysis to identify common themes.

Results indicate that graduates of Christian colleges did not differ noticeably from persons graduating from secular institutions in their initial reasons for choosing engineering. They also did not differ noticeably in their expression of a sense of calling (expressed as other-orientedness). Only about half of Christian college engineering alumni expressed an orientation towards service to others as a part of their engineering work. In order to better align with Christian college mission statements, faculty and engineering departments at such institutions are encouraged to seek ways to assist engineering students to be better prepared for recognizing and seeking out the other-oriented, service aspects of a professional career in engineering.

It is no secret that women are under-represented in engineering schools across the U.S. At Christ... more It is no secret that women are under-represented in engineering schools across the U.S. At Christian colleges, this disparity is even higher. Many programs are in place to attempt to increase the number of women engineers. Is this simply a case of political correctness run amok as policy, or do these programs represent a justifiable attempt to correct a serious problem?

The evidence, both biblical and psychological, supports that women are as capable as men of doing engineering work. Thus, from a justice standpoint, Christians should be concerned that there are not barriers preventing women from pursuing an engineering career. However, this is not to say that women and men are identical. In fact, women engineers likely would, on average, make different contributions to the field. Both from a moral standpoint and because of the practical benefits, Christians should be eager to embrace the richness that a more diverse workforce would bring to engineering.

In 2004, Ermer surveyed the status of women, both nationally and at Christian colleges. This paper presents updated data regarding the status of women (both students and faculty) at Christian engineering schools. New initiatives being tried at one Christian college in an attempt to improve the gender balance are presented. Reasons for the under-representation of women, both anecdotal and scholarly, are discussed. Some practical suggestions are provided for increasing the number of women graduating with engineering degrees.

Cambridge Scholars Publishing, 2022

SAGE Open, 2021

2019 ASEE Annual Conference & Exposition Proceedings

Proceedings of the American Society for Engineering Education Annual Conference, Jun 2015

Journal of Women and Minorities in Science and Engineering

Cultural influences, including family and friends
Recruitment activities to engineering, as experienced before entering college
Participation in engineering-related activities
Self-perception and self-efficacy
Motivations for studying engineering
Definitions of success, personally and academically
Perceptions of the learning environment.

2004 Annual Conference Proceedings

Christian faith is to be like yeast in bread dough, permeating every part of a life. Therefore, ... more Christian faith is to be like yeast in bread dough, permeating every part of a life. Therefore, it naturally also shapes the teaching, learning, and practice of engineering for Christian engineers. A Christian worldview will influence an engineer, whether or not it is acknowledged. Within a Christian engineering education, it is useful to explicitly delineate some of the ways that faith can and should influence engineering thought and practice. This paper presents some principles upon which a Christian engineering education should be based:

1. Engineers construct models in an attempt to study the mechanisms and systems under which God’s creation operates.

2. A Christian engineering education must shape the character as well as the mind.

3. In order to be effective kingdom servants, Christian engineers must learn professionalism.

4. Redemptive work is needed within the field of engineering.

However, even if the ideals are agreed upon, it is not always obvious how to achieve these goals in education. Some practical methods for how to incorporate Christian faith into education, in a yeast-like manner, are presented. While these are developed with a Christian liberal arts college in mind, many of the concepts could be relevant to an educator at a secular school.

Cambridge Scholars Publishers, 2022

This book presents a timely consideration of sexual harassment in engineering by putting it in co... more This book presents a timely consideration of sexual harassment in engineering by putting it in context with current events in the US: #MeToo, recent presidential administrations, the flurry of media and public interest in recent prominent harassment cases, and the COVID-19 pandemic. It provides a window into the experience of individual engineers, students, and faculty. For engineering practitioners, this book presents effective strategies for reducing sexual harassment that can be implemented in a wide range of settings. Researchers will appreciate its extensive review of the literature, including measurement scales, impacts of harassment, and identification of particularly vulnerable populations. This book also outlines where future research is needed in this regard. To view the Table of Contents, please click here.

first time through. Such thinking is required to identify broader issues, such as those related t... more first time through. Such thinking is required to identify broader issues, such as those related to safety or legality. Critical thinking ensures that the right analysis questions are asked. Good designers must be proficient communicators. A complex design must be understood by engineering team members during a peer review, by managers overseeing the project, by marketers attempting to sell the product, by customers considering purchasing the product, by regulators, and more. Communicating the essence of the design to each of these audiences requires skills in graphical, oral, and written communication. The designer must be adept with a variety of communication media, from email, to written reports, to visual presentations. She must be able to work with words, charts, figures, statistics, drawings, orthographic projections, mathematical equations, computational algorithms, and more. Finally, good designers must be multidisciplinary problem solvers. While the engineering education curriculum is cleanly split amongst various sub-disciplines, the real engineering products are never so easily broken down into constituent parts. The designer must be at least cognizant of many different disciplines that come together in any specific technological product, and must often have significant expertise in a few of them.

SAGE Open, 2021

Unmet or thwarted belonging needs have been implicated in multiple studies of women in engineerin... more Unmet or thwarted belonging needs have been implicated in multiple studies of women in engineering in college and in the engineering workforce. A wide range of other challenges that women face in engineering are tightly linked to deficits in belonging. Furthermore, many women face intersectional factors across race and ethnicity that make it even more difficult to belong. This literature review looks at women’s struggles in engineering in the context of the fundamental psychological need to belong. Studies that investigate belonging are reviewed, as are major contributors to unmet or thwarted belonging including gender identity threat and normative and numerical male dominance. Belonging is not the only psychological need that is inadequately met for women in engineering, but it is a common factor in multiple contexts and the situation worsens as women progress in their career pathways. Studies of belonging among women in engineering underscore the importance of supporting women in ...

2008 Annual Conference & Exposition Proceedings

2004 Annual Conference Proceedings

A novel first-year course (Engineering Chemistry and Materials Science) was created to broaden th... more A novel first-year course (Engineering Chemistry and Materials Science) was created to broaden the technical foundation in the BSE program at Calvin College. The content of the new course was drawn from two established courses-an engineering course in materials science (which was subsequently eliminated) and the second semester of first-year chemistry (which most engineering students did not previously take). In an innovative format, the course is team-taught by faculty from the engineering and chemistry departments. The material is integrated, so that the chemistry is motivated by relation to engineering properties, while the materials science is more thoroughly grounded in scientific principles. This allows greater conceptual depth for the materials science than was present in the previous stand-alone course. It also provides all engineering students with a greater chemistry background, and makes the chemistry seem more relevant and interesting. A weekly lab illustrates concepts, attracts the attention of hands-on learners, and is also integrative. For example, in one lab period students synthesize several polymers. The next lab period, they test various material properties of those polymers, relating these observations back to the structures they now know well. The course material is technical and challenging. Students enjoy the challenge, whereas the course previously taken by secondsemester freshmen bored many students because they found it too simple, and repetitive of the first-semester freshman design course. The new interdisciplinary course has been successful in two years of being taught. Students particularly appreciate the lab, saying it makes the lecture more interesting, relevant, and easier to understand. Faculty see more student engagement with the material. Initial data indicate significant improvement in first-year-to-sophomore year retention rates.

Christian faith is to be like yeast in bread dough, permeating every part of a life. Therefore, i... more Christian faith is to be like yeast in bread dough, permeating every part of a life. Therefore, it naturally also shapes the teaching, learning, and practice of engineering for Christian engineers. A Christian worldview will influence an engineer, whether or not it is acknowledged. Within a Christian engineering education, it is useful to explicitly delineate some of the ways that faith can and should influence engineering thought and practice. This paper presents four principles upon which a Christian engineering education should be based: 1. Engineers construct models in an attempt to study the mechanisms and systems under which God’s creation operates. 2. A Christian engineering education must shape the character as well as the mind. 3. In order to be effective kingdom servants, Christian engineers must learn professionalism. 4. Redemptive work is needed within the field of engineering. However, even if the ideals are agreed upon, it is not always obvious how to achieve these goa...

Journal of Molecular Recognition, 1998

Current Opinion in Biotechnology, 1999

Biotechnology Progress, 2000

Yeast surface display is a eucaryotic system for the directed evolution of protein binding and st... more Yeast surface display is a eucaryotic system for the directed evolution of protein binding and stability. For antibody affinity maturation, achievable single-pass enrichment factors are a critical variable. Both reliable recovery of rare clones (yield) and effective differentiation between clones of only slightly improved affinity (purity) are paramount. To validate yeast display's purification potential, trial sorting experiments were performed. The D1.3 (anti-hen egg lysozyme) single chain variable fragment antibody and a 2-fold higher affinity mutant (M3) were each displayed on the surface of Saccharomyces cerevisiae. M3-displaying cells were mixed into the D1.3-displaying cells at a ratio of 1:1000. Cells were fluorescently labeled according to antigen equilibrium binding and then sorted using a flow cytometer. Single-pass enrichment of M3-displaying cells was 125-fold ((65-fold). This level of performance is achievable because of the precision and reproducibility of optimal labeling conditions. This work further demonstrates the capability of yeast display for very fine discrimination between mutant clones of similar affinity. Because large improvements in affinity typically result from combinations of small changes, this capability to identify subtle improvements is essential for rapid affinity maturation.

2015 ASEE Annual Conference and Exposition Proceedings