Yearbook 06-07


Johannes Scheid
Home Institution Charité - Universitätsmedizin Berlin Host Institution Rockefeller University, New York, NY Mentor: Michael Nussenzweig, M.D. E-Mail: johannes.scheid@gmx.de
Research Topic see Abstract
Personal Reactions to the U.S. Experience One key experience I had during the months in New York is what great support you can count on if you are interested in what you are doing. Rockefeller University maintains a superb environment for people dedicated to science. This includes not only a broad variety of lecture series and big laboratories but also a superb location with a campus “park” in the midst of Manhattan. The second experience I definitely will take home is how much this environment trains you in listening. This place is full of people coming from all parts of the world, anxious to learn something about different ways of thinking. One outstanding example is my “bay-neighbor”, an Indian post doc who knows more about classical music literature than most of the music students I met in Germany.
Greatest Difficulties Encountered Oddly enough my greatest difficulty had to do with my apartment back home in Berlin. I had rented a piano in Berlin and the owner needed it back while I still was in New York; so from New York I had to manage a piano transport that had to go via another apartment because the staircase was too small….
Most humorous incident Here I will have to tell the story of a colleague from Japan who arrived in New York and started in a laboratory involved in bird studies. He was supposed to watch a certain species of birds, a task that led him, equipped with binoculars and a big microphone, near some private residences…. After he got into a lot of trouble, he probably had learned how to explain clearly what bird-watching means.
Helpful Hints for Future Students I think it is absolutely worthwhile to invest a lot of time looking for the right laboratory and university before you go to the US. Maybe you even want to go there earlier and take a look at a few institutions. Both the university you choose and the laboratory in which you work can have a great impact on your perception of your stay. Additionally, I think it does not always have to be the biggest university. Smaller Institutions have great advantages, and, in case of the Rockefeller University, even have a bigger output scientifically than most of the big universities.
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Abstract on Research Topic
A Further Checkpoint in B Cell Development

Author: Johannes Scheid

Institution:
Rockefeller University, New York, NY

Background:
In order to establish immune responses towards a vast number of antigens, B cell development includes a processes that constantly leads to the creation of self- and poly-reactivity. It remains elusive in which developmental stages self-reactivity of B cells is regulated in healthy humans and may be deregulated in patients suffering of autoimmune diseases such as SLE.
Over the last years our laboratory has established a method to reproduce antibodies and B cell receptors made by distinct B cell populations. Applying this method to the main stages of B cell development gave us the opportunity to test the antibodies and B cell receptors produced during different stages of B cell development for their self- and poly-reactivity.
This work resulted in the definition of three checkpoints for self-reactivity in the B cell development up to the stage of memory B cells.
Does the transition from the B cell memory to the plasma cell compartment in the bone marrow include a further checkpoint in which production of self-reactive antibodies is prevented, is the question we are momentarily addressing.

Materials and Methods:
Single plasma cells from four healthy donors were sorted (CD138+, CD38+, CD27+).
Ig genes were amplified, first with RT PCR then two rounds of nested single cell PCR, specific for the V and J genes. The second round introduced the restriction sites for cloning. After cloning heavy and light chains separately they were co-transfected in 293T cells and supernatants were collected after 4 days.
The supernatants are being tested for poly- and self-reactivity in ELISAs (against dsDNA, ssDNA, LPS, insulin and antinuclear antigens) and on HEP-2 slides.