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New window onto stem cells

Stem cells are perhaps the one biological entity that has given rise to the greatest number of dreams, hopes, frustration and disappointment over the last decade among scientists, doctors, people suffering from complicated health conditions and their family members. Now, at least in regard to Parkinson’s disease, a group of scientists from São Paulo appears to have found an important clue to partially explain the lack of success in therapy based on stem cell transplants and even older cell therapies that used the transplant of material extracted from the adrenal gland or brain of aborted fetuses.

This finding and the context in which the research for treatments for Parkinson’s, a disease, the spread of which is increasing in proportion to the ageing of the population, are developing, is well reported by our special editor, Marcos Pivetta, starting on page 16. He shows that if what the group of scientists is proposing in a study published in the April 19 on-line edition of Stem Cell Reviews and Reports is confirmed, fibroblasts may be just one of the other hitherto unidentified villains in this story. This is a type of skin cell that is very similar to some stem cells, but with totally different properties from the latter. Implanted into mice with Parkinson’s, along with mesenchymal stem cells (obtained from the umbilical cord of newborns), the fibroblasts eliminated the good results previously yielded by simply implanting stem cells during the experiment and also worsened the disease symptoms. What can one deduce from this? “Perhaps, many poor results in scientific work with cell therapies are due to this type of contamination,”  says geneticist Mayana Zatz. In other words, fibroblasts confused with stem cells and mixed together with them in implants might cause new problems for sick people who, in some parts of the world, are submitted to transplants without much control. These people should be warned of this. Furthermore, contamination may also be confusing real conclusions on the possible positive effects of cell therapies. The good side of this story is that once again an opportunity arises for experiments with pure and well-controlled mesenchymal stem cells in the treatment of Parkinson’s.

The second text I want to comment on in this issue is the excellent back-and-forth interview of our humanities editor, Carlos Haag, with historian Laura de Mello e Souza. To follow her words from page 10 on is to encounter the passionate way in which she deals with history, delving into archives that have rarely or never been dealt with to undertake each one of the journeys proposed “into the foreign country of the past.”  Indeed, she believes that this sentence by Hartley (British writer, Leslie Poles Hartley) in The Go-between is the great definition of what history is.

The interview also allows us to come into contact with Laura’s incisive critique of the excess of  “essayism”  of monographic studies and of angles in Brazilian historiographic production that are detrimental to more general approaches to our history. One must stress that she considers this production to be good, but since we jump stages, going into microhistory without seriously going into historicity, she sees a gap in production that obliges her to recommend, when someone asks her to indicate a general history of Brazil, the História geral da civilização brasileira [General history of Brazilian civilization] by Sérgio Buarque de Holanda, a work from the 1960s, but the most recent of its type. “I believe it’s preferable for us to get over this phase, that it’s possible to do monographic studies, but to provide general explanations as well,”  she says at a particular moment. Ever aware, Laura de Mello e Souza observes that there is an audience in Brazil that is hungry for history books and whose needs are met by professionals who work correctly, but who do not innovate, while there are innovative historians who do not reach the general public. She thinks that the next step needs to be taken by someone who is carrying out original research: writing for the general public.