Treating a Rare Immune Disorder with Mesenchymal Stem Cells

In the journal Stem Cells and Development, there is a case report from the University Hospital at Karolinska Institutet in Stockholm, Sweden of a 21-year-old man who suffered from a rare immune disorder and was treated with an infusion of mesenchymal stem cells (MSCs) from a donor.

This patient was seen in October, 2010 and had been suffering from a fever for 2 months. He had had a previous gastrointestinal infection that had resolved, but the inflammation that resulted from the infection refused to go away. He was diagnosed with hemophagic lymphohistiocytosis (HLH). This is a mouthful, but it is a relatively rare immune disorder that results in pronounced systemic hyperinflammation. This hyperinflammation essentially results from some sort of infection that causes inflammation, but the inflammation does not turn off when the infection resolves. The condition causes the spleen to enlarge and the number of blood cells to decrease to abnormally low levels and the patient has a constant, burning fever.

The medical team that treated this poor soul used steroids, and that worked from about a week. Then they tried the HLH-94 treatment protocol, which involves treating the patient with a combination of powerful immunosuppressive drugs; etoposide, (VP-16), corticosteroids, CyclosporinA, and, in some patients, intrathecal methotrexate, before the patient is given a bone marrow transplant. The HLH-94 protocol returned the patient to normal – for about 2 months, and then the patient was back to square one.

At this point, the medical team needed a Hail Mary, if you will. Therefore, they decided to use MSCs from a healthy donor. The patient was given a total of 124 million bone marrow-derived MSCs, and within 24 hours, the patient’s fever was gone and his blood work normalized.

Unfortunately, the poor chap contracted a nasty fungal infection that, in his weakened state, spread throughout his whole body and killed him. However, postmortem examinations showed that the MSCs had mobilized a whole gaggle of special white blood cells called macrophages, and these MSC-recruited macrophages suppressed the over-active immune response of this HLH patient. The fungal infection was contracted before the administration of the MSCs, therefore, the stem cell treatment had no causal relationship to the fungal infection.

However, this case study suggests that MSCs have a future in the treatment of immune disorders. Furthermore, the use of MSCs from donors can also provide therapeutic material for the treatment of immune disorders.