Flow cytometry-based quantification of cytokine levels in AML patients plasma and cell culture supernatants.

AIM: Bone marrow stromal cells (BMSCs) have been found to support leukemic cell survival; however, the mechanisms responsible are far from being elucidated yet. The main aim of the current study is to identify particular cytokine/chemokine patterns of acute myeloid leukemia (AML) cells, and, on a longer term, to correlate them with the patient outcome and response to therapy. Therefore, the influence of BMSCs on in vitro modulation of cytokine secretion (IL-1beta, TNF-alpha, IL-10, IFN-gamma, IL-4, IL-5, and IL-2) by AML cells as well as the AML cells supportive capacity of BMSCs-derived soluble factors was investigated. MATERIAL AND METHODS: With this purpose, we used an in vitro experimental model consisting in the evaluation of the effect of BMSC confluent layers-conditioning medium (BMSC-CM) on M4/5 AML cell cultures. RESULTS: Our results show that BMSC-CM from both AML patients and healthy subjects conferred a substantial beneficial effect on AML cells throughout the culture (p=0.0002 and 0.0020 respectively at 24 hours and p=0,0013 and 0,0030 respectively at 72 hours), with a temporary increase in AML cell viability conferred by BM plasma from AML patients. Significant differences were observed with respect to IL1 b secretion which was upregulated in AML cell cultures both after 24 and 72 hours following the addition of AML-BMSC-CM, in contrast to control-BMSC-CM. CONCLUSION: Our results suggest the contribution of BMSCs from AML patients to the generation of particular factors which may be key players involved in the in vivo maintenance of the malignant clone.

HLA-B57 is significantly associated with psoriasis in Northeast Romania [corrected].

UNLABELLED: The aim of the study was to identify HLA class I types associated with susceptibility to psoriasis among population of Northeast region of Romania. PATIENTS AND METHODS: 27 psoriatic patients and 89 controls were typed serologically for HLA-A and HLA-B lymphocyte expression using CDC-NIH (complement dependent-cytotoxicity--National Institute of Health) method. The Terasaki plates used for HLA class I typing were prepared in our laboratory using antisera of known specificities. RESULTS AND CONCLUSIONS: psoriatic patients in the group of study frequently express HLA-B57 phenotype. The relative risk induced by this phenotype was highly statistically significant (p = 0.0016) while HLA-B13 was not associated with a significant risk for developing psoriasis in patients under study compared with controls (p = 0.48). Also, HLA-B27 (p = 0.96) and HLA-B44 (p = 0.99), reported by others to be associated with late psoriasis, do not meet (a particular) disease susceptibility between psoriatic patients under investigation.