Bone Marrow May Give Rise to Blood Cancers

(HealthDay News) -- Defects in bone marrow can lead to abnormal blood cells that cause precancerous blood diseases in mice, two new studies find.

Blood cells are produced in the bone marrow. It was previously thought that red blood cells themselves were the source of these precancerous diseases, which can sometimes progress to leukemia.

In humans, these precancerous conditions can be difficult to treat, because not much is known about what causes the blood cells to become abnormal, explained researcher Louise Purton, who is affiliated with the Peter MacCallum Cancer Center in Australia, as well as Massachusetts General Hospital and the Harvard Stem Cell Institute in Boston.

Purton said her team found "that the bone marrow microenvironment can make the blood cells become abnormal, like a type of pre-leukemic disease."

The second study was conducted by a team led by Stuart Orkin, a Howard Hughes Medical Institute investigator at Children's Hospital Boston and chairman of pediatric oncology at the Dana-Farber Cancer Institute.

"The defect we see isn't intrinsic to the blood cells themselves. It's a result of the interaction of the blood and support cells in bone marrow. We didn't predict that at all," Orkin said in a prepared statement.

The findings from the two studies, published in the June 15 issue of the journal Cell, could help in the development of new treatments for precancerous blood diseases.

"At the moment, most doctors focus on the blood cell as being the cause of the disease. Hopefully, the (bone marrow) microenvironment will now also be considered as a potential cause, which might lead to better treatments for these patients in the future," Purton said.

More information
The American Society of Hematology has more about blood diseases.

Flu Shot Kick-Starts Fetal Immune System

(HealthDay News) -- Giving flu vaccinations to a pregnant woman kick-starts the immune system of her fetus, a U.S. study says.

The researchers, led by Rachel Miller of the Columbia University Medical Center, used a newly developed technique called MHC tetramer staining to analyze B- and T-cell immune responses in umbilical cord blood after pregnant women were vaccinated with Fluzone.

Anti-Fluzone antibodies were detected in about 40 percent of the blood cord samples. MHC tetramer staining showed that some of the blood cord samples also made T-cells specifically against the vaccine.

These and other findings in the study establish that B- and T-cell responses to antigens occur in utero after pregnant women have received flu vaccinations, the study authors said. This supports the theory that the human neonatal system can respond to environmental exposures.

The findings have important implications for determining when immune responses to environmental exposures begin, the researchers said.

The study is published in the June 1 issue of the Journal of Clinical Investigation.

Influenza vaccinations for pregnant women are considered safe and are recommended by the U.S. Centers for Disease Control and Prevention.

More information
The March of Dimes Birth Defects Foundation has more about vaccinations during pregnancy

Poor Bond With Siblings May Boost Depression Risk

(HealthDay News) -- Men who don't get along with a sibling might be at higher risk for depression, new research shows.

"Among a group of men studied since their late teens, those who said they didn't have a close relationship with even one of their siblings were more likely to be depressed by the time they were 50," said study author Dr. Robert Waldinger, director of the Study of Adult Development at Brigham and Women's Hospital, in Boston.

"Having a close relationship with even one of your siblings made you less likely to be depressed," Waldinger added.

His team published the report in the June 1 issue of the American Journal of Psychiatry.
In the study, Waldinger and his colleagues collected data on 229 men from the time they were teens until they were in their 50s. The researchers looked at the men's quality of life and their relationships with their siblings, the quality of parenting they had, and any family history of depression.

The study has lasted for 68 years and is one of the longest studies of adult psychosocial development ever done, Waldinger noted.

His group found that the two things that predicted depression at 50 were poor relationships with brothers and sisters during childhood and a family history of depression.

The researchers aren't clear about what their finding means. "It could be that not being close to a sibling is an early harbinger of later depression," Waldinger said. "Or it could be that being close to a sibling helps you develop you skills dealing with peers."

"There is this connection," Waldinger said. "But we are not sure why."

One expert said the study provides valuable new insight into the origins of mental illness.

"This long-term study allows a unique opportunity to examine the relationship between early life development and long-term risk for common mental health and substance use problems," said Dr. Gregory Simon, a psychiatrist and mental health researcher at the Group Health Cooperative, in Seattle.

While this study suggests a strong relationship between childhood sibling relationships and adult depression, direction of that relationship can't be determined, Simon said.

"It is certainly possible that poor relationships with siblings during childhood have significant and enduring negative effects on mental health," Simon said. "It is also possible, however, that poor relationships with siblings are one of the early signs of depressive illness."

More information
For more information on depression, visit the U.S. National Institute on Mental Health.