Cytokine-Induced Killer (CIK) Cells, In Vitro Expanded under Good Manufacturing Process (GMP) Conditions, Remain Stable over Time after Cryopreservation.

Cytokine-induced killer (CIK) cells are advanced therapy medicinal products, so their production and freezing process has to be validated before their clinical use, to verify their stability as a drug formulation according to the good manufacturing practice (GMP) guidelines. We designed a stability program for our GMP-manufactured CIK cells, evaluating the viability, identity and potency of cryopreserved CIK cells at varying time periods from freezing, and compared them with fresh CIK cells. We evaluated the effects of the cryopreservation method, transportation, and the length of time of different process phases (pre-freezing, freezing and post-thawing) on the stability of CIK cells. This included a worst case for each stage. The expanded CIK cells were viable for up to 30 min from the addition of the freezing solution, when transported on dry ice within 48 h once frozen, within 60 min from thawing and from 12 months of freezing while preserving their cytotoxic effects. The reference samples, cryopreserved simultaneously in tubes and following the same method, were considered representative of the batch and useful in the case of further analysis. Data obtained from this drug stability program can inform the accurate use of CIK cells in clinical settings.

In Vitro Mesenchymal Progenitor Cell Expansion is a Predictor of Transplant-related Mortality and acute GvHD III-IV After Bone Marrow Transplantation in Univariate Analysis: A Large Single-Center Experience.

Mesenchymal stromal cells (MSCs) are multipotent stem cells able to differentiate into mesenchymal origin tissue and support the growth of hematopoietic stem cells. In order to understand the role of MSCs infused in bone marrow grafts, 53 consecutive patients were analyzed for engraftment, acute and chronic graft-versus-host disease (GvHD), transplant-related mortality (TRM), relapse incidence, and overall survival. The MSC content was measured as MSC expansion at the second passage. When in vitro-expanded MSC (cumulative population doubling at second passage, cPDp2) values were stratified according to the median value (2.2-fold increase), the univariate analysis showed a significant difference in TRM (23% vs. 3.8%, P=0.05.) and in acute GvHD III-IV incidence (12% vs. 4%, P=0.04), while the multivariate analysis did not confirm its independent role. No clinical parameters in donors and recipients were identified as predictors of cPDp2 expansion. Our study suggests a role for short-term ex vivo-expanded MSCs in reduced aGVHD III-IV incidence and TRM in univariate analysis. A multicenter, larger study is warranted to confirm these data.

Correction to: Cytokines induced killer cells produced in good manufacturing practices conditions: identification of the most advantageous and safest expansion method in terms of viability, cellular growth and identity.

Following publication of the original article [1], the authors reported that all of the authors' names were processed incorrectly so that their given and family names were interchanged. In this Correction the correct author names are shown. The original publication of this article has been corrected.

Cytokines induced killer cells produced in good manufacturing practices conditions: identification of the most advantageous and safest expansion method in terms of viability, cellular growth and identity.

BACKGROUND: Cytokine-induced killer (CIK) cells are a very promising cell population raising growing interest in the field of cellular antitumor therapy. The aim of our study was to validate the most advantageous expansion method for this advanced therapy medicinal product (ATMP) and to translate it from preclinical field to good manufacturing practices (GMP). GMP ensures that ATMP are consistently produced and controlled to the quality standards required to their intended use. For this reason, the use of the xenogenic sera tended to be minimized by GMP for their high variability and the associated risk of transmitting infectious agents. RESULTS: We decided to replace Fetal Bovine Serum (FBS), largely used as medium supplement for CIKs expansion, with other culture media. Firstly, Human Serum (HS) and Human Pool Plasma (HPP) were tested as medium supplements giving not compliant results to acceptance criteria, established for CIKs, probably for the great batch to batch variability. Consequently, we decided to test three different serum free expansion media: X-VIVO 15, (largely used by other groups) and Tex Macs and Cell Genix GMP SCGM: two GMP manufactured media. We performed a validation consisting in three run-sand even if the small number of experiments didn't permit us to obtained statistical results we demonstrated that both X-VIVO 15 and Tex Macs fulfilled the quality standards in terms of cellular growth, viability and identity while Cell Genix GMP SCGM resulted not compliant as it caused some technical problems such as high mortality. CONCLUSION: In conclusion, these preclinical validation data lay the bases for a GMP-compliant process to improve the CIKs expansion method.