He pioneered immunotherapy mediated by allogeneic donor lymphocytes and innovative methods for stem cell transplantation to cure hematological malignancies and solid tumors.

[8] These observations confirmed the therapeutic benefits of cell therapy and led to the development of new concepts for treating hematologic malignancies and solid tumors.

As a rule, treatment of cancer focuses on a two-step approach: tumor debulking using conventional and innovative modalities, followed by immunotherapy of minimal residual disease.

[11][12] Baxter International recognized the potential of cell therapy and signed an agreement that resulted in significant investment with Slavin at Hadassah Medical Center.

Slavin, along with his team, used a vector provided by the San Raffaele Hospital in Milan to pioneer the first successful use of gene therapy for the treatment of bubble baby born with adenosine deaminase deficiency in 2002.

[16][17] More recently, Slavin introduced personalized anti-cancer immunotherapy, focusing on the use of activated donor lymphocytes targeted against cancer with monoclonal and bispecific antibodies.

Initially, Slavin pioneered the use of monoclonal antibodies anti-CD52 (Alemtuzumab, now approved by FDA as Lemtrada) for prevention of graft-vs-host disease (GVHD), the most serious complication of allogeneic stem cell transplantation, and later on for treatment of CLL[22] and multiple sclerosis.

[30] Based on the cumulative experience using cell therapy, in recent years, Slavin and his team also focused on using multi-potential bone marrow, adipose tissue, or placenta & cord tissue-derived MSCs for regenerative medicine, pioneering the use of MSCs for the treatment of orthopedic indications including cartilage repair and new bone formation[31][32] as well as for repair of renal function[33] in addition to continuous treatment of neuroinflammatory, neurodegenerative disorders and traumatic neurological disorders.

Slavin's primary research and clinically applied discoveries were represented in over 600 published articles and more than 900 national and international scientific presentations, resulting in global impact in several disciplines mostly related to cellular therapy for treating malignant and nonmalignant disorders.

The unique efficacy of intentionally mismatched donor lymphocytes using killer cells activated before and following cell infusion was translated into a new paradigm for cellular therapy of cancer based on the use of the transient circulation of non-engrafting donor lymphocytes targeted against minimal residual disease as a new approach for the potential cure of cancer at an early stage of the disease.

[39] Later on, introducing the concept of post-transplant deletion of alloreactive lymphocytes by cyclophosphamide by Slavin's team[40] made it possible to provide a relatively safe and non-expensive transplant procedure for patients with no matched donor available using a haploidentical family member.