Repurposing a transplant drug for bone growth

The transplant immunosuppressant drug FK506, also known as tacrolimus or Prograf, can stimulate bone formation in both cell culture and animal Read more

Beyond the amyloid hypothesis: proteins that indicate cognitive stability

If you’re wondering where Alzheimer’s research might be headed after the latest large-scale failure of a clinical trial based on the “amyloid hypothesis,” check this Read more

Mother's milk is OK, even for the in-between babies

“Stop feeding him milk right away – just to be safe” was not what a new mother wanted to hear. The call came several days after Tamara Caspary gave birth to fraternal twins, a boy and a girl. She and husband David Katz were in the period of wonder and panic, both recovering and figuring out how to care for them. “A nurse called to ask how my son was doing,” says Caspary, a developmental Read more

Beth Israel Deaconess Medical Center

General-heavy army disastrous in immune battle

Immunologists have identified two big groups of T cells: “helper” CD4+ cells and “killer” CD8+ cells.* The helper cells can produce immune regulatory molecules and promote antibody responses, while the killer cells recognize and destroy virally-infected cells.

A vaccine against a virus that stimulates only helper CD4+ cells leads to uncontrolled lethal inflammation in mice once the animals are challenged with the virus, a recent paper in Science shows. Emory Vaccine Center director Rafi Ahmed is a co-author.

Senior author Dan Barouch, from Harvard/Beth Israel Deaconess Medical Center, tells The Scientist that CD4+ cells are like generals directing the battle of the immune system and “if you just have strategic generals and no soldiers, it turns out to be worse than having no army at all.” Rebalancing the system with antiviral CD8+ T cells or antibodies helps limit the problems.

The findings mesh with work by Yerkes investigators [Guido Silvestri and colleagues] suggesting that HIV vaccines that boost CD4+ cells in gateway mucosal tissues lead to higher rates of infection. In both cases, the lesson is: having more helper CD4+ T cells around actually does not help. Read more

Posted on by Quinn Eastman in Immunology Leave a comment