CONTENTS:

• Autoimmune Diseases May Be Triggered by Cells from Your Mother
  
  
• Study Reveals Gender Affects Lung Cancer Development
  
  
• Differences in Smoking and Lung Transplant Outcomes Explored

Autoimmune Diseases May Be Triggered by Cells from Your Mother
(CW HENDERSON PUBLISHER www.newsfile.com) -- Autoimmune diseases, in which the body attacks its own tissues, may in some cases be triggered by cells from your mother that have been lurking within you since you were in the womb.

Researchers also have evidence that women may contract autoimmune diseases because of cells from their fetuses that persisted for decades after crossing the placenta.

Many autoimmune conditions appear similar to graft-versus-host disease, in which cells from a transplanted organ mount an immune response against the host. That has led some researchers to speculate that microchimerism - a condition in which small numbers of another person's cells persist in the body - could be involved in some cases of autoimmunity. The idea is bolstered by the fact that autoimmune diseases are more common in women, who may be repeatedly exposed to their fetuses' cells while pregnant, according to a report in the April 24, 1999, issue of the New Scientist.

Two years ago, researchers in Boston, Massachusetts, made the surprising discovery that fetal cells can survive in a woman for as long as 27 years after her last pregnancy. Since then, other studies have shown that women with autoimmune diseases such as scleroderma, which causes the skin to become thick and leathery and can damage internal organs, seem to have an unusually high incidence of microchimerism.

In one study, male cells were detected in 32 out of 69 women with scleroderma, but just one out of 25 women who did not have the disease. Women with scleroderma and microchimerism also seem to have 10 or more times as many foreign cells in their bodies as women with microchimerism who are not suffering from any autoimmune disease.

The problem with the theory has been that men get autoimmune diseases, too. But, at the Experimental Biology '99 meeting in Washington, DC, researchers announced that maternal cells can also cross over to fetuses and survive for decades.

J. Lee Nelson and her colleagues at the University of Washington in Seattle hunted for maternal cells in a 47-year-old man with scleroderma, using the polymerase chain reaction (PCR) to search for the gene for a molecule found on the surface of his mother's cells but not his own. Sure enough, they found maternal cells.

The researchers also looked at blood from a 15-year-old boy with lupus, another autoimmune disease that attacks the skin and internal organs, using a technique that stains X-chromosomes one color and Y chromosomes another. They were able to find a female cell, which has two X-chromosomes, and using PCR they confirmed that it came from the boy's mother.

Nelson admits that she is still some way from proving that maternal cells can trigger autoimmunity. "But I think they're likely to be a significant piece of the puzzle," she says.

Antony Rosen, an expert on autoimmunity at Johns Hopkins University in Baltimore, Maryland, says, "It's at that stage where the hypothesis is reasonable and the preliminary data are supportive. But you can't get unequivocal data in a minute."

Carol Artlett of Thomas Jefferson University in Philadelphia, Pennsylvania, who has found maternal cells in five out of eight men suffering from scleroderma, says that microchimerism cannot be the whole story, as it can occur in people without autoimmune disease. Artlett suggests that autoimmunity can arise when a trigger such as a viral infection spurs the foreign cells to begin attacking their host. This reaction disrupts the host's immune system so that it joins the attack against the body's own tissues, she believes.

Women's Health Weekly: May 3, 1999 issue (excerpted with permission)

Study Reveals Gender Affects Lung Cancer Development
(CW HENDERSON PUBLISHER www.newsfile.com) -- Once again evidence said that differences exist between the sexes.

Researchers have discovered that men and women may not in fact be equal - at least with respect to the pattern of precancerous lesions in the lungs of current and former smokers.

Dr. Adi Gazdar, University of Texas Southwestern professor of pathology, Dr. Stephen Lam and colleagues in Canada, and other investigators at the National Cancer Institute in Bethesda, Maryland, have published the first study that analyzes the gender differences in precancerous changes in smokers' lung tissue. This study, in the April 21, 1999, issue of the Journal of the National Cancer Institute, finds that women develop a different pattern of bronchial changes than men do; that airflow obstruction, a common means to assess those at risk of lung cancer, does not seem to be valid especially for women; and that lung damage due to smoking persists for many years and probably for life.

More men and women die from lung cancer than from any other type of cancer. In 1999, an estimated 171,600 new cases of lung cancer will be diagnosed, and 158,000 people will die from this disease. Approximately 50 percent of lung cancer occurs in former smokers. Women are more susceptible to the harmful effects of tobacco-related carcinogens - the odds ratios for major types of lung cancer are consistently higher in women than in men at every level of exposure to cigarette smoke. Furthermore, this gender difference cannot be explained by differences in baseline exposure, smoking history or body size; it is likely due to women's higher susceptibility to tobacco carcinogens.

"Cancer is the result of a complex multistep process," said Gazdar, associate director of the Nancy B. and Jake L. Hamon Center for Therapeutic Oncology Research. "We are actively trying to develop methods of early detection and chemoprevention - ways to chemically reverse precancerous lesions and block cancer development - for those at high risk."

The scientists found that men had a significantly higher incidence of precancerous lesions in the large central airways than women. They also found that fewer women than men had high-grade preinvasive lesions. Because women develop more cancers in the peripheral (outer) parts of the lung than men do, Gazdar and co-workers presume that women smokers are selectively damaging these parts of the lung, while smoking damage in men targets the larger, more centrally located airways.

The take-home lesson from this study is that methods of lung-cancer screening in high risk populations must take gender into consideration, and perhaps, different screening procedures and criteria will have to be used for men and for women.

The research is funded by the NCI, the U.S. National Institutes of Health, and a NIH-funded SPORE (Specialized Program of Research Excellence) in Lung Cancer.

Women's Health Weekly: May 3, 1999 issue (excerpted with permission)

Differences in Smoking and Lung Transplant Outcomes Explored
(CW HENDERSON PUBLISHER www.newsfile.com) -- New findings on the different reasons men and women smoke, lung transplant outcomes and gender, and the risk of heart attack from a common asthma medication in people with heart disease were discussed by an expert panel at the American Lung Association/American Thoracic Society International Conference, held in San Diego, California, during April 1999.

Men are more likely than women to grab a cigarette if they're angry, anxious, sad, or tired, a new study presented at the conference suggested. Smoking also is more likely to decrease anger and sadness in men, according to the study, conducted by Dr. Ralph Delfino and Dr. Larry Jamner at the University of California, Irvine.

The study included 25 women and 35 men ages 18 to 42, who made three diary entries an hour, for up to 48 hours, recording their mood and smoking behavior. The urge to smoke was more strongly associated with anger, anxiety, and alertness in men than in women; feelings of sadness or fatigue were linked with the urge to smoke in men only. Smoking seemed to decrease feelings of anger in those men who got angry more often, and to decrease feelings of sadness in men, but not in women. Smoking was associated with feelings of happiness in women, but not in men.

These findings suggest possible gender differences in the effect of nicotine on the central nervous system, possibly because of different interactions with hormones, according to the researchers. "The commonly held belief before this study was that women smoked more for emotional reasons, but this does not appear to be the case in the real-life settings measured in this study," Delfino said.

"The results are consistent with the hypothesis that women are smoking less for mood control than men, and that social interactions may play a more important role in why women smoke. Ongoing research using similar diary techniques in adolescents may reveal targets for early preventive interventions."

The findings suggest that smoking prevention and cessation programs might be more successful if they had different approaches for males and females, and if they targeted people according to their personality profile, Delfino noted. "For instance, hostile people who smoke for mood-altering effects might benefit from an anger-management program," he said.

There is a significant risk associated with transplanting lungs from male donors into female recipients, according to a study presented at the meeting. Researchers at the University of Wisconsin-Madison have studied 116 lung transplants, 19 of which were male donor organs transplanted into female recipients.

Graft outcome was assessed by either lung transplant failure/death or by poor function due to chronic rejection. They found that the rate of graft survival (a functioning transplanted lung) with good function was 29 percent at 24 months after transplantation for the male donor lung into female recipient combination. In contrast, the overall two-year rate for all other patients was 69 percent. Specifically, the two-year graft survival rate with good function was 87 percent in female-to-male transplants; 81 percent in female-to-female transplants; and 60 percent in male-to-male transplants.

The study findings appear somewhat unique to lung transplantation, because an increased incidence of graft failure (destruction of the transplanted lung, usually associated with death of the recipient due to respiratory failure) with this donor-recipient gender combination has not been identified for kidney or liver transplantation, said Dr. Keith C. Meyer. "The lungs are much more prone to injury than kidneys and livers," he noted. "Unlike kidneys and livers, with lungs there's no time to do tissue matching. We have to transplant the lung quickly."

He said that male-to-female lung transplants need to be studied at other transplant centers.

Approximately 1,000 to 1,200 lung transplants are performed in the United States each year, according to Meyer. About half of recipients of transplanted lungs are emphysema patients who developed the disease after years of smoking, he said.

Women's Health Weekly: May 10, 1999 issue (excerpted with permission)

CWH Journal Watch: June 1999