Efficacy of adoptively transferred allogeneic CIK cells on colorectal cancer: Augmentative antitumoral effects of GvHD.

OBJECTIVE: A preclinical study was designed to evaluate the effects of adoptively transferred cytokine-induced killer (CIK) cells on colorectal adenocarcinoma. METHODS: Forty NOG mice bearing HT-29 xenograft tumors were developed and equally divided into 2 groups of treatment and control. The mice in the treatment group received cumulatively 40-60 × 106 CIK cells in four divided doses. RESULTS: Median tumor doubling times for HT-29 xenograft tumors in the treatment and control groups were found to be 8.98 and 4.32 days; respectively. The treatment resulted in tumor growth delay (TGD) of 52.5 %. CIK cell-induced log cell kill (LCK) was found to be 0.67, which implies reduction of 78.6 % of neoplastic colorectal cells. Median length of survival in the treated mice was significantly longer than controls (57 (41-63) vs 41 (31-57) days, P < 0.001). Mice in the treatment group experienced graft-versus-host disease (GvHD) from median of day 13th after the cell therapy. LCK and TGD significantly increased after emergence of GvHD. After necropsy, tumors of the treatment group contained high levels of human-originated CD3+, CD4+ and CD8+ cells and showed significantly lower mitotic counts (P < 0.001) and residual tumor scores (P = 0.005) than the controls (entirely negative for the mentioned CD markers). Ninety percent of the treated mice were found to be responding. CONCLUSIONS: Adoptive transfer of allogeneic CIK cells may be an efficient antitumoral therapy for colorectal cancer. Allogeneic CIK cell-mediated GvHD may contribute to amplification of graft-versus-tumor effects of the cellular therapy.

Specific egg yolk antibody raised to biofilm associated protein (Bap) is protective against murine pneumonia caused by Acinetobacter baumannii.

Acinetobacter baumannii easily turns into pan drug-resistant (PDR) with a high mortality rate. No effective commercial antibiotic or approved vaccine is available against drug-resistant strains of this pathogen. Egg yolk immunoglobulin (IgY) could be used as a simple and low-cost biotherapeutic against its infections. This study evaluates the prophylactic potential of IgY against A. baumannii in a murine pneumonia model. White Leghorn hens were immunized with intramuscular injection of the recombinant biofilm-associated protein (Bap) from A. baumannii on days 0, 21, 42, and 63. The reactivity and antibiofilm activity of specific IgYs raised against the Bap was evaluated by indirect ELISA and a microtiter plate assay for biofilm formation. The IgYs against Bap were able to decrease the biofilm formation ability of A. baumannii and protect the mice against the challenge of A. baumannii. IgYs antibody raised here shows a good antigen-specificity and protectivity which can be used in passive immunotherapy against A. baumannii. In conclusion, the IgY against biofilm-associated protein proves prophylactic in a murine pneumonia model.

In vivo study of the angiogenesis potential of bone marrow-derived mesenchymal stem cell aggregates in their niche like environment.

BACKGROUND: Sufficient blood vessel formation in bioengineered tissues is essential in order to keep the viability of the organs. Impaired development of blood vasculatures results in failure of the implanted tissue. The cellular source which is seeded in the scaffold is one of the crucial factors involved in tissue engineering methods. MATERIALS AND METHODS: Considering the notable competence of Bone Marrow derived Mesenchymal Stem Cell aggregates for tissue engineering purposes, in this study BM-aggregates and expanded BM-MSCs were applied without any inductive agent or co-cultured cells, in order to investigate their own angiogenesis potency in vivo. BM-aggregates and BM-MSC were seeded in Poly-L Lactic acid (PLLA) scaffold and implanted in the peritoneal cavity of mice. RESULT: Immunohistochemistry results indicated that there was a significant difference (p < 0.050) in CD31+ cells between PLLA scaffolds contained cultured BM-MSC; PLLA scaffolds contained BM-aggregates and empty PLLA. According to morphological evidence, obvious connections with recipient vasculature and acceptable integration with surroundings were established in MSC and aggregate-seeded scaffolds. CONCLUSION: Our findings revealed cultured BM-MSC and BM-aggregates, capacity in order to develop numerous connections between PLLA scaffold and recipient's vasculature which is crucial to the survival of tissues, and considerable tendency to develop constructs containing CD31+ endothelial cells which can contribute in vessel's tube formation.

Generation of CD19-Targeted Chimeric Antigen Receptor T Cells.

BACKGROUND: Current advancements in the field of chimeric antigen receptor (CAR) therapy, particularly U.S. FDA approval of Kymriah and Yescarta, heralds a new era of cancer treatment. This rapid progress in technology has urged more countries and institutions to keep pace with the fast-growing and developing technology of producing CAR T cell-based therapies in the race to develop new cancer-targeting drugs. Hence, for stepping in line with global advances and to pave the way for subsequent preclinical and clinical studies, we have established a development protocol for a cancer-targeting CAR T cell; we have chosen CD19 CAR T cell as a well-defined model to set-up T cell expansion, activation, and viral transduction as the prerequisites for diverse CAR T cell therapies. METHODS: T cells from peripheral blood mononuclear cells (PBMCs) were activated and expanded. CD19 CAR lentiviral particles were produced in the Lenti-X™ 293T Cell Line using PolyFect Transfection Reagent. RESULTS: Activation protocol resulted in (65 ± 4%; P = 0.046) increase in the rate of activated T cells 24 hours after the initiation of the procedure. The expansion methodology resulted in a high purity of the T cell population (96 ± 3%) in the pool of PBMCs within 14 days of the procedure. Finally, 35 ± 6% of T cells were transduced with CD19 lentivirus with MOI of 3. CONCLUSION: Collectively, the results of this study prove that we have successfully overcome the first hurdle on the road to reach CAR T cell technology which is the prerequisite for developing preclinical and clinical phases of CAR therapy in settings with basic resources.

Directly injected native bone-marrow stem cells cannot incorporate into acetaminophen-induced liver injury.

The paucity of liver donation highlights the use of cell-based strategies for end-stage liver failure. We recently showed that bone marrow-derived aggregates (BMDAs) can completely restore the hematopoietic system in gamma-irradiated mice. These aggregates are stem and progenitor cells in the bone marrow (BM), composed of both hematopoietic and non-hematopoietic lineages. Furthermore, reports showed that resident BM cells migrate to the liver and integrate themselves into the tissue in small numbers. Hence, we hypothesized that direct delivery of BMDAs to the damaged liver might enhance the integration of BM cells in the liver because of its stemness property, intact BM architecture, the physical proximity of these niche-like structures to the damaged sites and the existence of liver paracrine factors. To this aim, we made an acute liver model by intraperitoneal injection of acetaminophen. Then, GFP-expressing BMDAs were intrahepatically injected. Despite the detection of GFP-expressing cells five days after intrahepatic injection, these cells were not detectable at days 15 and 60, indicating that the puzzle of BM cell integration in the liver still has more missing pieces other than stemness, physical proximity, and paracrine factors. Actually, it seems that even intact BM structures need further signals to be qualified for integration.