Relapsed acute myeloid leukemia (AML) is a significant post-transplant complication lacking standard treatment and associated with a poor prognosis. Cellular therapy, which is already widely used as a treatment for several hematological malignancies, could be a potential treatment alternative. Natural killer (NK) cells play an important role in relapse control but can be inhibited by the leukemia cells highly positive for HLA class I. In order to restore NK cell activity after their ex vivo activation, NK cells can be combined with conditioning target cells. In this study, we tested NK cell activity against KG1a (AML cell line) with and without two types of pretreatment-Ara-C treatment that induced NKG2D ligands (increased activating signal) and/or blocking of HLA-KIR (killer-immunoglobulin-like receptors) interaction (decreased inhibitory signal). Both treatments improved NK cell killing activity. Compared with target cell killing of NK cells alone (38%), co-culture with Ara-C treated KG1a target cells increased the killing to 80%. Anti-HLA blocking antibody treatment increased the proportion of dead KG1a cells to 53%. Interestingly, the use of the combination treatment improved the killing potential to led to the death of 85% of KG1a cells. The combination of Ara-C and ex vivo activation of NK cells has the potential to be a feasible approach to treat relapsed AML after hematopoietic stem cell transplantation.

• MeSH
• akutní myeloidní leukemie imunologie   terapie   MeSH
• buňky NK účinky léků   imunologie   transplantace   MeSH
• cytarabin farmakologie   MeSH
• imunosupresiva farmakologie   MeSH
• imunoterapie metody   MeSH
• klinické zkoušky jako téma MeSH
• kultivované buňky MeSH
• lektinové receptory NK-buněk - podrodina K imunologie   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• receptory KIR imunologie   MeSH
• signální transdukce MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

To elucidate the immunological mechanisms critical for tumor progression, we bred novel mouse strains, different in the NKC and H-2D domains. We used inbreeding to generate hybrids of Balb/c and C57BL/6 of stable H-2Db+d-NK1.1neg and H-2Db-d+NK1.1high phenotypes. We analyzed the growth of three established MHC class I-deficient tumor cell lines: TC-1/A9 tumor (HPV-associated) and B16F10 melanoma, both syngeneic to C57BL/6, and the MCB8 (3-methycholanthrene-induced tumor) syngeneic to Balb/c. Furthermore, we induced colorectal carcinoma by azoxymethane-DSS treatment to test the susceptibility to chemically-induced primary cancer. We found that the novel strains spontaneously regressed the tumor transplants syngeneic to both Balb/c (MCB8) and C57BL/6 (B16F10 and TC-1/A9) mice. The H2-Db+d-NK1.1neg, but not the H2-Db-d+NK1.1high strain was also highly resistant to chemically-induced colorectal cancer in comparison to the parental mice. The immune changes during TC-1/A9 cancer development involved an increase of the NK cell distribution in the peripheral blood and spleen along with higher expression of NKG2D activation antigen; this was in correlation with the time-dependent rise of cytotoxic activity in comparison to C57BL/6 mice. The TC-1/A9 cancer regression was accompanied by higher proportion of B cells in the spleen and B220+/CD86+ activated antigen-presenting B cells distributed in the lymphoid organs, as well as in the periphery. The changes in the T-cell population were represented mainly by the prevalence of T helper cells reflected by grown CD4/CD8 ratio, most prominent in the b+d-NK1.1neg strain. The results of the present study imply usefulness of the two novel mouse strains as an experimental model for further studies of tumor resistance mechanisms.

• MeSH
• buňky NK imunologie   patologie   MeSH
• experimentální nádory genetika   imunologie   patologie   MeSH
• histokompatibilita - antigeny třídy I genetika   imunologie   MeSH
• lektinové receptory NK-buněk - podrodina K biosyntéza   imunologie   MeSH
• lidé MeSH
• myši inbrední BALB C MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• regulace genové exprese u nádorů genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Mucosal-associated invariant T (MAIT) cells contain two main subpopulations, CD8(+) and double-negative (DN) cells. The first reports suggested that subpopulations of MAIT cells have similar phenotype and function. Recent works, however, demonstrate that the subpopulations have different ontogenesis and are differentially affected by xenobiotic treatment. In this work, we re-examined the possible differences between subpopulations of MAIT cells. We demonstrate that the main subpopulations of MAIT cells (CD8 and DN) are relatively uniform in terms of both phenotype and function. Both populations are memory/activated, tissue-homing and pro-inflammatory. CD8(+) MAIT cells are better equipped for pro-inflammatory functions as they express higher levels of CD16 and NKG2D, produce more pro-inflammatory cytokines (TNF-α and IFN-γ) and have higher cytotoxic potential (contain more granzyme B and express higher levels of CD107A upon stimulation). Our study contributes to the understanding of the heterogeneity of MAIT cell population.

• MeSH
• biologické markery metabolismus   MeSH
• buněčný rodokmen imunologie   MeSH
• CD8-pozitivní T-lymfocyty cytologie   imunologie   MeSH
• dospělí MeSH
• exprese genu MeSH
• GPI-vázané proteiny genetika   imunologie   MeSH
• granzymy genetika   imunologie   MeSH
• imunofenotypizace MeSH
• imunologická paměť * MeSH
• interferon gama genetika   imunologie   MeSH
• lektinové receptory NK-buněk - podrodina K genetika   imunologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• MAIT buňky cytologie   imunologie   MeSH
• membránový protein 1 asociovaný s lyzozomy genetika   imunologie   MeSH
• receptory IgG genetika   imunologie   MeSH
• TNF-alfa genetika   imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Invariant natural killer T (iNKT) cells, CD1d restricted T cells, are involved in the immune responses against various infection agents. Here we describe their behavior during reactivation of human herpes simplex virus (HSV). iNKT cells exhibit only discrete changes, which however, reached statistically significant level due to the relatively large patient group. Higher percentage of iNKT cells express NKG2D. iNKT cells down-regulate NKG2A in a subset of patients. Finally, iNKT cells enhance their capacity to produce TNF-α. Our data suggests that iNKT cells are involved in the immune response against HSV and contribute mainly to its early, innate phase.

• MeSH
• aktivace lymfocytů MeSH
• aktivace viru MeSH
• antigeny CD1d genetika   imunologie   MeSH
• dospělí MeSH
• exprese genu MeSH
• herpes simplex imunologie   patologie   virologie   MeSH
• lektinové receptory NK-buněk - podrodina K genetika   imunologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• NKT buňky imunologie   patologie   MeSH
• přirozená imunita * MeSH
• senioři MeSH
• Simplexvirus fyziologie   MeSH
• TNF-alfa genetika   imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH