Antibody-coated NK cells – A new hope to treat blood cancer

Clinical trials incorporating synthetic biology have seen instances of interesting technological elevation in cancer cell therapies. Researchers have crafted a potential variety of immune cells named Natural Killer (NK) cells which have been equipped to incorporate a surface protein assisting them in attacking the tumorous cells. This has carved out a new therapeutic treatment for cancer cells which is much more effective and gentler than using CAR-T cell therapy and dealing with its extreme side effects.

The American Association for Cancer Research had reported at an annual meeting about the successful shrinkage of tumors in most people diagnosed with blood cancer. The reason is the use of the new version of therapy harnessing the immune cells of the patient itself, to treat tumor growths. These Natural Killer Cells are ideally harvested from the blood that is either donated or extracted from the umbilical cord. Thus, it does not produce any negative immune response in the body of the patient being subjected to cancer therapy.

Also, Chimeric Antigen Receptor (CAR)-T cell therapy is extremely convoluted and demands exorbitant monetary rates. With the motive to overcome such challenges, scientists have been successful at devising protein drugs (bispecific antibodies) having two arms. One of the arms binds to the tumor and the other sticks to the NK cells. The sole purpose of the involvement of these bispecific antibodies is to form a link between the tumor cells and the NK cells so as to assist the NK cells to attack the tumor.

 

 

Reports suggest trials conducted using a bispecific antibody, AFM13 which, however, worked not as the researchers expected it to. AFM13 could link NK cells to a CD30 marker on lymphoma cells and was trialed on a patient which did not give any positive results.

MD Katy Rezvani (Anderson Cancer Center) along with her colleagues investigated the matter and concluded that the patient’s NK cells must have been problematic and weaker to function. Thus, they strategized to blend the AFM13 with NK cells which were donated, in her laboratory. To it, cytokines were added to augment its vigor. 22 severely ill patients who had undergone various treatments for Hodgkin’s lymphoma were trialed with the first step being chemotherapy to dig out space for donated cells to be infused. After so, cells encoded with AFM13 were infused into the patients’ body which was extracted from blood from an umbilical cord. The observations were incredible and showcased the shrinkage of enormous tumors within days. Out of the 22, tumors vanished completely in 13 who were dosed with NK cells the highest and tumors shrank in about 17-19 of them without any serious side effects.

Although there have been observations suggesting a resumption of the growth of tumors in a few of the 13 patients, a lot of progress in their health has been measured, who would otherwise have died without the shrinkage. It is evident that this treatment strategy can pave the way to even if not cure the disease totally in some patients, but at least enable shrinkage of tumors for years.

 

References:

1. “Synthetic Antibody–Immune Cell Complex Dramatically Shrinks Blood Tumors | Science | AAAS.” Synthetic Antibody–Immune Cell Complex Dramatically Shrinks Blood Tumors | Science | AAAS, www.science.org, 11 Apr. 2022, https://www.science.org/content/article/synthetic-antibody-immune-cell-complex-dramatically-shrinks-blood-tumors.