John Marchalonis dies

The researcher was one of the first to identify the molecular basis of immune recognition

Written byKelly Rae Chi
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John Marchalonis, whose research helped create the fields of autoimmunity and immune system evolution, died of cancer on June 22. He was 66.During his career, 20 years of which was spent at the University of Arizona in Tucson, Marchalonis published studies on topics ranging from mechanisms of human autoimmune disease to the evolution of the immune system in sharks and other vertebrates. He wrote eight books and published more than 370 articles. "Jack was an extraordinary man in many ways," said Samuel Schluter, also from the University of Arizona, who collaborated with Marchalonis for 20 years. "He was close to being a genius. He would always come up with ideas. It's going to be a challenge to continue with the science because we're going to miss his ideas." Marchalonis was also known for supporting a colleague in his department who reported abuse of funds at the University of Arizona, an action which began a series of scientific misconduct inquiries and ended in her dismissal.Forty years ago, Marchalonis was "one of a small group of pioneering scientists" who started applying biochemical and then molecular genetic approaches to the study of evolutionary immunobiology, Greg Warr, of the Medical University of South Carolina who worked with Marchalonis for 10 years, wrote in an Email to The Scientist. "His influence on the field, through his own research and the young scientists he trained, was immense."Marchalonis was widely recognized for using sharks (the most ancient organism of the vertebrate lineage) in the molecular and evolutionary investigation of the vertebrate immune system. His research "questioned how close human immunity was to other species' immunity," said Marlys Witte, from the University of Arizona. "He was very humble in terms of recognizing how much there was to discover, and how to question the dogma."In 1992, Marchalonis, Schluter and colleagues cloned and compared antibody gene sequences of two distant shark species, finding that the sequences differed substantially in the two species, which diverged more than 200 million years ago. The study, cited 55 times, also compared shark antibody sequences to those of other vertebrates and found similarities in sequence but differences in sequence arrangement. The functional significance of the differences were not known at the time, but the work led Marchalonis and colleagues to surmise that antibody regulation in the sharks was significantly different from the process in higher vertebrates. Marchalonis's work in autoimmunity helped build the foundation for research on diseases including systemic lupus erythematosus, multiple sclerosis and rheumatoid arthritis. In 1992, Marchalonis' group was one of the first to show that humans have autoantibodies to T-cell receptors, suggesting the immune system recognizes and regulates itself in both healthy humans and those with autoimmune disorders. The group generated synthetic fragments of T-cell receptors and found that human IgG recognizes certain characteristic patterns of the receptors. The study was cited 146 times.Marchalonis' most highly cited study, published in 1969 in Biochemistry Journal, described a new method for labeling antibodies and cell surface proteins called lactoperoxidase-catalyzed radioiodination. The study was cited 1,475 times, and for more than a decade became a standard technique for visualizing cell surface proteins. Marchalonis frequently joked with the lab that he thought of the technique while having a beer with colleagues after work, Schluter said.Marlys Witte, a professor of surgery, said she would regularly discuss the lymphatic system with Marchalonis, during departmental lunches. "He was the only basic scientist who came regularly and talked with us. He was truly a translational scientist. We valued very much having him here, and he was very down to earth. We will miss him and his conversation and his questions greatly," Witte said.Marchalonis was also known as a staunch supporter of his colleagues. As chair of the microbiology and immunology department in the late 90s, he defended faculty member Marguerite Kay when she was accused of mismanaging her lab and publishing faulty data. Marguerite Kay, then an Alzheimer's researcher in the microbiology and immunology department at University of Arizona, said she discovered that the university was overcharging on grants and billing the Department of Veterans Affairs tens of thousands of dollars for work never done, according to the Phoenix New Times. In 1996, the university began a series of scientific misconduct inquiries into Kay's research, ending in Kay's dismissal from the university in 2000. She argued she was investigated and dismissed because of her accusations, not misconduct.Kay planned to sue the university on multiple grounds, but the case was thrown out because of a missed deadline by her lawyer, Carol Bernstein, a colleague in the microbiology and immunology department with Marchalonis and Kay, told The Scientist. (Bernstein, a former president of the Arizona chapter of the American Association of University Professors, said Kay enlisted her to help in 1996, when the problems began.) After her dismissal, Kay moved to Europe and then Texas to work in labs of her colleagues, Bernstein said.Kay was employed as a senior research scientist full time in the department of natural sciences and mathematics at the University of Texas at Dallas, from August 2004 until February of 2006, according to the university's human resources department. The department did not have information on her current whereabouts and was unable to release contact information. Bernstein said Kay now lives in Texas but declined to give updated contact information. Kay could did not respond to Email requests for comment."Jack had a great deal of loyalty to his faculty and he defended [Kay] right to the end. He believed that she was innocent," Schluter said. Kelly Rae Chi mail@the-scientist.comLinks within this article:John Marchalonis http://uanews.org/cgi-bin/WebObjects/UANews.woa/wa/MainStoryDetails?ArticleID=14008V. S. Hohman et al., "Complete sequence of a cDNA clone specifying sandbar shark immunoglobulin light chain: gene organization and implications for the evolution of light chains," Proc Natl Acad Sci, Jan 1, 1992. http://www.the-scientist.com/pubmed/172969J. J. Marchalonis et al., "Human autoantibodies reactive with synthetic autoantigens from T-cell receptor beta chain," Proc Natl Acad Sci, April 15, 1992. http://www.the-scientist.com/pubmed/1565623J. J. Marchalonis, "An enzymic method for the trace iodination of immunoglobulins and other proteins," Biochem J., June 1969. http://www.the-scientist.com/pubmed/4185494T. W. Durso, "New Alzheimer's drug signals a coming increase in research," The Scientist, Jan. 20, 1997. http://www.the-scientist.com/article/display/17353/R. Nelson, "Committing the truth," Phoenix New Times, July 13, 2000. http://www.phoenixnewtimes.com/2000-07-13/news/committing-the-truth
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