2B4: potential immune target for sepsis survival

Emory immunologists have identified a potential target for treatments aimed at reducing mortality in sepsis, an often deadly reaction to Read more

EHR data superior for studying sepsis

Analysis of EHR data says sepsis rates and mortality have been holding steady, contrary to what is suggested by after-the-fact Read more

New pediatric digestive/liver disease gene identified by international team

A multinational team of researchers describes a newly identified cause of congenital diarrhea and liver disease in Read more

multiple myeloma

Lampreys and the reverse spy problem

Call it the reverse spy problem. If you were a spy who wanted to gain access to a top secret weapons factory, your task would be to fit in. The details of your employee badge, for example, should look just right.

As described in this 2016 JCI Insight paper, Emory and University of Toronto investigators wanted to do the opposite. They were aiming to develop antibody tools for studying and manipulating plasma cells, which are the immune system’s weapons factories, where antibody production takes place. The situation is flipped when we’re talking about antibodies. Here, the goal is to stand out.

Do these guys look like good spies?

Monoclonal antibodies are classic biomedical tools (and important anticancer drugs). But it’s tricky to develop antibodies against the places where antibodies themselves are made, because of the way the immune system develops. To guard against autoimmune disease, antibodies that would react against substances in the body are often edited out.

To get around this obstacle, researchers used organisms that have very different immune systems from humans: lampreys. Emory’s Max Cooper and colleagues had already shown how lampreys have molecules — variable lymphocyte receptors or VLRs — that function like antibodies, but don’t look like them, in terms of their molecular structure.

From the paper:

We reasoned that the unique protein architecture of VLR Abs and the great evolutionary distance between lampreys and humans would allow the production of novel VLRB Abs against biomedically relevant antigens against which conventional Abs are not readily produced because of structural or tolerogenic constraints.

Senior author Goetz Ehrhardt, now at University of Toronto, used to be in Cooper’s lab, and their two labs worked together on the JCI Insight paper. Read more

Posted on by Quinn Eastman in Immunology Leave a comment

Landmark study in blood stem cell transplant

Before all the excitement about embryonic stem cells, doctors were using hematopoetic – that is, blood-forming — stem cells. Hematopoetic stem cells can replenish all the types of cells in the blood, and are the centerpiece of transplantation as treatment for diseases such as multiple myeloma or leukemia. They can come from two different places: directly from the marrow of a donor’s hip bone, or indirectly from the donor’s blood after a drug nudges the stem cells out of the bone marrow.

Most hematopoetic stem cell transplants in the United States now use the indirect method of obtaining the stem cells. Until this fall, gold-standard randomized clinical trial results were not available to say which method is best for patient outcomes. Winship Cancer Institute hematologist Ned Waller was a key co-author of a study that was published in October in the New England Journal of Medicine addressing this question.

The trial involved 48 centers enrolling 551 patients as part of the Bone Marrow and Clinical Trials Network (BMT CTN).  Waller helped design the study, and his lab at Winship analyzed the cells in each type of graft as the central core lab for the trial.

The study found no significant difference in the overall Ray Ban Italia survival rate at two years, and no difference in relapse rates or in acute graft-versus-host-disease (GVHD). However, there was a significantly higher rate of chronic GVHD with the use of blood stem cells.

GVHD, a difficult and sometimes life-threatening complication for this type of transplant, involves damage inflicted by the transplant recipient’s new immune system upon the liver, skin and digestive system.

This finding will generate serious discussion among leaders in the transplant field about whether bone marrow or peripheral blood stem cell transplantation is a better treatment option, Waller says. A text Q + A with him follows.

What was surprising about the results of this study?

The equivalent survival was expected, and the increased chronic GvHD in recipients of blood stem cell grafts was suspected. What is surprising is that the relapse rate was similar between the two arms, in spite of the PBSC arm having more chronic GvHD.

The accompanying editorial argues bone marrow should be the standard for unrelated-donor transplants. Do you agree?

Yes, with the exceptions that Fred mentioned: patients with life-threatening infections and patients at high risk for graft rejection.

What are the differences, procedurally, between bone marrow and peripheral blood as sources for hematopoetic stem cell transplant?

Donating bone marrow involves a two or three hour surgical procedure requiring general anesthesia, in which bone marrow is removed from the hip bone with a needle and syringe.  For peripheral blood stem cells, the donor undergoes five days of injections of granulocyte colony-stimulating factor and then a four-hour apheresis procedure to harvest stem cells from the blood. Blood stem cell donors have bone pain during the 5-day period of cytokine treatment, and bone marrow donors have more discomfort early after donation, but symptoms for both BM and PBSC donors have typically resolved by four weeks after donation.

What proportion of each is now in use here?

Marrow is the graft source in about 25% of recipients of grafts from unrelated donors, 10% in recipients of grafts from related donors.

What proportion of HSCT is unrelated donor?

For allogeneic transplants, about 60% receive grafts form unrelated donors (33% matched related donors and 7% mis-matched related donors).

What kind of information does this study provide oncologists/hematologists about which option to use in which situation?

Marrow should be preferred in recipients of grafts from unrelated donors when the conditioning regimen is myeloablative [substantially damages the patient’s existing bone marrow].

Does it depend on the type of leukemia/myeloma, the age or other conditions of the patient etc?

This study only enrolled patients with acute leukemia and MDS [myelodysplastic syndrome]. It excluded patients with myeloma or lymphoma. Ages included children, adults up to 60.

What other types of studies in this area are being conducted at Winship?

We are studying the role of different constituents in the graft (BM and PBSC) to determine which are most important in shaping transplant outcomes (relapse, GvHD). We have an active pre-clinical research program utilizing mouse models to address specific questions related to engraftment cell homing and specific pathways related to immune activation. In addition, we will participate in a clinical trial of a new way of mobilizing blood stems that avoids the need for five days of G-CSF and uses a CXCR4 antagonist called plerixafor to mobilize PBSC. The properties of the plerixafor-mobilized PBSC may be more similar to BM cells with respect to GvHD.

Posted on by Quinn Eastman in Cancer Leave a comment

When bone marrow goes bad

Plasma cells live in our bone marrow. Their job: to make antibodies that protect us from bacteria and viruses. But if those plasma cells grow unchecked, that unchecked growth leads to multiple myeloma.

Sagar Lonial, MD

Multiple myeloma is a type of cancer that results in lytic bone disease, or holes in the bones. What’s more, the cancerous cells crowd out normal bone marrow resulting in anemia or a low white count, leaving a person vulnerable to infections.

Sagar Lonial, MD, an oncologist at Winship Cancer Institute, Emory University, treats people with multiple myeloma. The prognosis for people with this type of cancer is poor; however, researchers are gaining on the disease. Twenty years ago, the survival rate was two to three years; now, it’s four to five.

Lonial says one of the keys to improving patients’ prognosis is increasing their enrollment in clinical trials and better access to life-extending drugs.

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Posted on by Robin Tricoles in Cancer Leave a comment

Emory University Hospital celebrates 3000th bone marrow transplant


An Emory University Hospital patient recently prepared to celebrate a “birthday” with family, friends and caregivers  – but this was no typical birthday according to any calendar or tradition.

Instead, cheerful songs and celebratory clapping echoed through the halls of the Bone Marrow Transplant Unit at Emory University Hospital, as always when a potentially life-saving bone marrow transplant is about to occur. And the tradition did not stop on May 20, as the unit physicians, nursing staff, patients and hospital administrators gathered to celebrate the 3000th transplant.

Encouraged by Emory’s success, Edmund Waller, MD, PhD, director of Emory’s Bone Marrow and Stem Cell Transplant Center says, “While 3,000 is a nice round number, it’s the middle of a growing and successful program. After 3,000 procedures, I know we all look forward to the future of this program.”

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Posted on by Lance Skelly in Uncategorized Leave a comment