Optimizing natural killer (NK) cell alloreactivity could further improve outcome after allogeneic hematopoietic cell transplantation (alloHCT). The donor's Killer-cell Immunoglobulin-like Receptor (KIR) genotype may provide important information in this regard. In the past decade, different models have been proposed aiming at maximizing NK cell activation by activating KIR-ligand interactions or minimizing inhibitory KIR-ligand interactions. Alternative classifications intended predicting outcome after alloHCT by donor KIR-haplotypes. In the present study, we aimed at validating proposed models and exploring more classification approaches. To this end, we analyzed samples stored at the Collaborative Biobank from HLA-compatible unrelated stem cell donors who had donated for patients with acute myeloid leukemia (AML) or myelodysplastic neoplasm (MDS) and whose outcome data had been reported to EBMT or CIBMTR. The donor KIR genotype was determined by high resolution amplicon-based next generation sequencing. We analyzed data from 5,017 transplants. The median patient age at alloHCT was 56 years. Patients were transplanted for AML between 2013 and 2018. Donor-recipient pairs were matched for HLA-A, -B, -C, -DRB1, and -DQB1 (79%) or had single HLA mismatches. Myeloablative conditioning was given to 56% of patients. Fifty-two percent of patients received anti-thymocyte-globulin-based graft-versus-host disease prophylaxis, 32% calcineurin-inhibitor-based prophylaxis, and 7% post-transplant cyclophosphamide-based prophylaxis. We tested several previously reported classifications in multivariable regression analyses but could not confirm outcome associations. Exploratory analyses in 1,939 patients (39%) who were transplanted from donors with homozygous centromeric (cen) or telomeric (tel) A or B motifs, showed that the donor cen B/B-tel A/A diplotype was associated with a trend to better event-free survival (HR 0.84, p=.08) and reduced risk of non-relapse mortality (NRM) (HR 0.65, p=.01). When we further dissected the contribution of B subtypes, we found that only the cen B01/B01-telA/A diplotype was associated with a reduced risk of relapse (HR 0.40, p=.04) while all subtype combinations contributed to a reduced risk of NRM. This exploratory finding has to be validated in an independent data set. In summary, the existing body of evidence is not (yet) consistent enough to recommend use of donor KIR genotype information for donor selection in routine clinical practice.

• Klíčová slova
• allogeneic hematopoietic cell transplantation (alloHCT), donor selection, killer-cell immunoglobulin-like receptor (KIR), prediction model, risk of relapse,
• MeSH
• akutní myeloidní leukemie * terapie   MeSH
• genotyp MeSH
• histokompatibilita * MeSH
• lidé středního věku MeSH
• lidé MeSH
• ligandy MeSH
• myelodysplastické syndromy * terapie   MeSH
• prognóza MeSH
• receptory KIR * genetika   MeSH
• transplantace hematopoetických kmenových buněk * normy   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ligandy MeSH
• receptory KIR * MeSH

BACKGROUND: Hepatitis B virus (HBV) infection is one of the most common infections worldwide, having negative impact on world health due to the tendency for chronification with late complications such as liver cirrhosis and hepatocellular carcinoma. Natural killer (NK) cells as part of innate antiviral defense influence the clinical course of HBV infection: elimination of the virus or chronic disease. AIM: Therefore, we investigated the polymorphisms of the main gene systems, regulating NK-cell function: killer cell immunoglobulin-like receptors (KIRs) and their appropriate HLA class I ligands in 144 HBV infected patients (124 chronic carriers and 20 spontaneously recoved) and 126 ethnically matched healthy controls from the Bulgarian population in a case-control study. METHODS: KIRs and HLA ligands were determined by PCR-SSP or PCR high-resolution typing methods. RESULTS: KIR2DL5B allele variant was significantly less frequent in spontaneously recovered (SR) patients compared to healthy controls (10.0% vs. 45.5%, Pcorr=0.006). The presence of KIR3DL1*004 allele was higher in chronic HBV carriers (CH) than in controls (33.1% vs. 17.6%, Pcorr=0.036). Additionally, SR patients differed from healthy individuals by the lower frequency of HLA-Bw4Ile80 group ligands (30.0% vs 63.7%, P=0.015). Three KIR genotypes were found more frequent in healthy in comparison with HBV infected individuals: ID2 (13.5% vs 5.6%, P=0.025), KIR genotype containing 6 activating KIRs (18.0% vs 7.6%, P=0.017), and KIR genotype composed of 4 activating and 5 inhibitory KIRs (23.8% vs 5.6%, P=0.001). CONCLUSION: These data suggest that inherited KIR and HLA class I ligand polymorphisms may influence the clinical course of HBV infection.

• Klíčová slova
• KIR HLA ligands, hepatitis B infection, killer immunoglobuline-like receptors,
• MeSH
• genotyp MeSH
• hepatitida B * genetika   MeSH
• imunogenetika MeSH
• lidé MeSH
• ligandy MeSH
• nádory jater * MeSH
• receptory KIR genetika   MeSH
• receptory KIR2DL5 MeSH
• studie případů a kontrol MeSH
• virus hepatitidy B genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• KIR2DL5B protein, human MeSH Prohlížeč
• ligandy MeSH
• receptory KIR MeSH
• receptory KIR2DL5 MeSH

Killer cells immunoglobulin-like receptors (KIRs) are a family of inhibitory and activating receptors expressed mainly by natural killer (NK) cells and few subsets of T lymphocytes. KIRs regulate NK cells' activity through interactions with specific HLA class I molecules and other yet unknown ligands presented on target cells. At present, 17 KIR genes and pseudogenes have been identified. As the number of KIR genes in different haplotypes varies, a wide range of genotypes in different ethnic populations may be observed. In our study, 125 healthy non-related Czech individuals were KIR typed both by sequence-specific primers and by sequence-specific oligonucleotide KIR genotyping methods. Thirty-eight different genotypes were observed in the Czech population and all 16 KIR genes known to date were found. Framework genes KIR 3DL3, KIR 2DL4, KIR 3DL2 and the pseudogene KIR 3DP1 were present in all individuals. The most frequent non-framework KIR genes detected in the Czech population were: KIR 2DL1 (95%), KIR 3DL1 (94%), KIR 2DS4 (92%) and the pseudogene 2DP1 (94%). Human leucocyte antigen (HLA)-C typing demonstrated prevalence of the C1/C2 heterozygosity (43%) and C1 homozygosity (41%) over the C2 heterozygosity. One hundred and twenty individuals from our panel carried at least one inhibitory KIR for the corresponding HLA-C group found in the genotype. Gene frequencies and found genotypes demonstrated similarity of the Czech population's KIR repertoire with the KIR repertoires of other Caucasian populations studied before.

• MeSH
• běloši genetika   MeSH
• frekvence genu * MeSH
• lidé MeSH
• pseudogeny MeSH
• receptory KIR genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• receptory KIR MeSH

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.

• Klíčová slova
• HLA-KIR, NK cells, NKG2D ligands, relapsed AML,
• 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
• Názvy látek
• cytarabin MeSH
• imunosupresiva MeSH
• KLRK1 protein, human MeSH Prohlížeč
• lektinové receptory NK-buněk - podrodina K MeSH
• receptory KIR MeSH

Despite the independent segregation of genes encoding killer immunoglobulin-like receptor (KIR) and human leukocyte antigen (HLA), there is some evidence of some kind of co-evolution. Therefore, one could expect reduced KIR diversity within the HLA restricted population. A total of 41 unrelated individuals homozygous for ancestral HLA haplotype AH8.1 (HLA-A*0101-Cw*0701-B*0801-DRB1*0301-DQB1*0201) were genotyped for KIRs. Over all, 14 different genotypes were identified. The KIR genes and genotypes repertoire generally mirror the published frequencies in Caucasians. Except for KIR2DS4, all activating genes presented frequencies below 50%. KIR2DS5 was the least frequent among activating genes (17%), whereas KIR2DL5 (37%) among inhibitory ones. The most frequent (39%) was AA genotype. Twenty-two individuals (54%) had a copy of KIR haplotypes A and B (AB genotype), whereas three (7%) were homozygous for B (BB genotype). Nine of fourteen reported genotypes occurred only in one individual. Five genotypes were reported in less than twenty individuals worldwide and one genotype was reported so far only once. Conversely, the three most frequent genotypes account for 68% of all detected genotypes. The results show the unrestricted KIR diversity in this HLA uniform group and support the fact that the driving force for KIR evolution is not exclusively a major histocompatibility complex.

• MeSH
• DNA analýza   genetika   MeSH
• frekvence genu MeSH
• genotyp MeSH
• haplotypy genetika   MeSH
• HLA antigeny genetika   MeSH
• homozygot MeSH
• lidé MeSH
• polymerázová řetězová reakce MeSH
• populační skupiny genetika   MeSH
• receptory KIR genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• HLA antigeny MeSH
• receptory KIR MeSH

BACKGROUND: The mammalian Leukocyte Receptor Complex (LRC) chromosomal region may contain gene families for the killer cell immunoglobulin-like receptor (KIR) and/or leukocyte immunoglobulin-like receptor (LILR) collections as well as various framing genes. This complex region is well described in humans, mice, and some domestic animals. Although single KIR genes are known in some Carnivora, their complements of LILR genes remain largely unknown due to obstacles in the assembly of regions of high homology in short-read based genomes. METHODS: As part of the analysis of felid immunogenomes, this study focuses on the search for LRC genes in reference genomes and the annotation of LILR genes in Felidae. Chromosome-level genomes based on single-molecule long-read sequencing were preferentially sought and compared to representatives of the Carnivora. RESULTS: Seven putatively functional LILR genes were found across the Felidae and in the Californian sea lion, four to five genes in Canidae, and four to nine genes in Mustelidae. They form two lineages, as seen in the Bovidae. The ratio of functional genes for activating LILRs to inhibitory LILRs is slightly in favor of inhibitory genes in the Felidae and the Canidae; the reverse is seen in the Californian sea lion. This ratio is even in all of the Mustelidae except the Eurasian otter, which has a predominance of activating LILRs. Various numbers of LILR pseudogenes were identified. CONCLUSIONS: The structure of the LRC is rather conservative in felids and the other Carnivora studied. The LILR sub-region is conserved within the Felidae and has slight differences in the Canidae, but it has taken various evolutionary paths in the Mustelidae. Overall, the process of pseudogenization of LILR genes seems to be more frequent for activating receptors. Phylogenetic analysis found no direct orthologues across the Carnivora which corroborate the rapid evolution of LILRs seen in mammals.

• Klíčová slova
• KIR, LILR, Leukocyte Receptor Complex, carnivora, felids, long-read sequencing,
• MeSH
• Canidae * MeSH
• Carnivora * genetika   MeSH
• Felidae * MeSH
• fylogeneze MeSH
• genomika MeSH
• lachtani * MeSH
• leukocyty MeSH
• lidé MeSH
• Mustelidae * MeSH
• myši MeSH
• receptory imunologické genetika   MeSH
• receptory KIR genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• receptory imunologické MeSH
• receptory KIR MeSH

Natural killer (NK) cells have important functions in immunity. NK recognition in mammals can be mediated through killer cell immunoglobulin-like receptors (KIR) and/or killer cell lectin-like Ly49 receptors. Genes encoding highly variable NK cell receptors (NKR) represent rapidly evolving genomic regions. No single conservative model of NKR genes was observed in mammals. Single-copy low polymorphic NKR genes present in one mammalian species may expand into highly polymorphic multigene families in other species. In contrast to other non-rodent mammals, multiple Ly49-like genes appear to exist in the horse, while no functional KIR genes were observed in this species. In this study, Ly49 and KIR were sought and their evolution was characterized in the entire family Equidae. Genomic sequences retrieved showed the presence of at least five highly conserved polymorphic Ly49 genes in horses, asses and zebras. These findings confirmed that the expansion of Ly49 occurred in the entire family. Several KIR-like sequences were also identified in the genome of Equids. Besides a previously identified non-functional KIR-Immunoglobulin-like transcript fusion gene (KIR-ILTA) and two putative pseudogenes, a KIR3DL-like sequence was analyzed. In contrast to previous observations made in the horse, the KIR3DL sequence, genomic organization and mRNA expression suggest that all Equids might produce a functional KIR receptor protein molecule with a single non-mutated immune tyrosine-based inhibition motif (ITIM) domain. No evidence for positive selection in the KIR3DL gene was found. Phylogenetic analysis including rhinoceros and tapir genomic DNA and deduced amino acid KIR-related sequences showed differences between families and even between species within the order Perissodactyla. The results suggest that the order Perissodactyla and its family Equidae with expanded Ly49 genes and with a potentially functional KIR gene may represent an interesting model for evolutionary biology of NKR genes.

• MeSH
• frekvence genu genetika   MeSH
• fúze genů MeSH
• fylogeneze MeSH
• genom genetika   MeSH
• jednonukleotidový polymorfismus genetika   MeSH
• koně genetika   MeSH
• lektinové receptory NK-buněk - podrodina A genetika   MeSH
• molekulární sekvence - údaje MeSH
• počítačová simulace MeSH
• receptory buněk NK chemie   genetika   metabolismus   MeSH
• savčí chromozomy genetika   MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční homologie aminokyselin MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• lektinové receptory NK-buněk - podrodina A MeSH
• receptory buněk NK MeSH

UNLABELLED: GABAB receptors are the G-protein coupled receptors for the main inhibitory neurotransmitter in the brain, GABA. GABAB receptors were shown to associate with homo-oligomers of auxiliary KCTD8, KCTD12, KCTD12b, and KCTD16 subunits (named after their T1 K+-channel tetramerization domain) that regulate G-protein signaling of the receptor. Here we provide evidence that GABAB receptors also associate with hetero-oligomers of KCTD subunits. Coimmunoprecipitation experiments indicate that two-thirds of the KCTD16 proteins in the hippocampus of adult mice associate with KCTD12. We show that the KCTD proteins hetero-oligomerize through self-interacting T1 and H1 homology domains. Bioluminescence resonance energy transfer measurements in live cells reveal that KCTD12/KCTD16 hetero-oligomers associate with both the receptor and the G-protein. Electrophysiological experiments demonstrate that KCTD12/KCTD16 hetero-oligomers impart unique kinetic properties on G-protein-activated Kir3 currents. During prolonged receptor activation (one min) KCTD12/KCTD16 hetero-oligomers produce moderately desensitizing fast deactivating K+ currents, whereas KCTD12 and KCTD16 homo-oligomers produce strongly desensitizing fast deactivating currents and nondesensitizing slowly deactivating currents, respectively. During short activation (2 s) KCTD12/KCTD16 hetero-oligomers produce nondesensitizing slowly deactivating currents. Electrophysiological recordings from hippocampal neurons of KCTD knock-out mice are consistent with these findings and indicate that KCTD12/KCTD16 hetero-oligomers increase the duration of slow IPSCs. In summary, our data demonstrate that simultaneous assembly of distinct KCTDs at the receptor increases the molecular and functional repertoire of native GABAB receptors and modulates physiologically induced K+ current responses in the hippocampus. SIGNIFICANCE STATEMENT: The KCTD proteins 8, 12, and 16 are auxiliary subunits of GABAB receptors that differentially regulate G-protein signaling of the receptor. The KCTD proteins are generally assumed to function as homo-oligomers. Here we show that the KCTD proteins also assemble hetero-oligomers in all possible dual combinations. Experiments in live cells demonstrate that KCTD hetero-oligomers form at least tetramers and that these tetramers directly interact with the receptor and the G-protein. KCTD12/KCTD16 hetero-oligomers impart unique kinetic properties to GABAB receptor-induced Kir3 currents in heterologous cells. KCTD12/KCTD16 hetero-oligomers are abundant in the hippocampus, where they prolong the duration of slow IPSCs in pyramidal cells. Our data therefore support that KCTD hetero-oligomers modulate physiologically induced K+ current responses in the brain.

• Klíčová slova
• G-protein coupled receptor, GABA-B, GPCR, KCTD12, KCTD16, Kir3,
• MeSH
• CHO buňky MeSH
• Cricetulus MeSH
• draslíkové kanály genetika   metabolismus   MeSH
• elektrofyziologické jevy genetika   MeSH
• excitační postsynaptické potenciály genetika   MeSH
• kinetika MeSH
• křečci praví MeSH
• metoda terčíkového zámku MeSH
• mozek - chemie genetika   MeSH
• myši knockoutované MeSH
• myši MeSH
• receptory GABA-B genetika   metabolismus   MeSH
• receptory KIR metabolismus   MeSH
• receptory spřažené s G-proteiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• křečci praví MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• draslíkové kanály MeSH
• receptory GABA-B MeSH
• receptory KIR MeSH
• receptory spřažené s G-proteiny MeSH

BACKGROUND: The selection of optimal donor is crucial for successful hematopoietic stem cell transplantation (HSCT). Thereby, it is appropriate to know, in addition to basic human leukocyte antigen (HLA) gene matches, other immunogenic or nonimmunogenic parameters predicting the outcome of transplant. OBJECTIVE: A unified approach is necessary to provide a comprehensive view of the patient-donor compatibility characterization outside of standard HLA genes. The approach should be applicable as a tool for optimizing procedures for extended donor typing and/or verification typing of a donor. METHODS: The study used the summary, unification, and innovation of existing practical knowledge and experience of the Czech National Marrow Donor Registry of various factors beyond HLA matching with impact on transplant outcome. RESULTS: An information technology system-implemented procedure (a verification algorithm) is presented as the decision support approach for prematurely discarding less suitable donors from the transplantation process. It is intended primarily for the transplant specialist to help establish optimal procedures for verifying and determining donor critical factors. CONCLUSIONS: A process defining HLAs, killer cell immunoglobulin-like receptors, and cytokine typing strategies was proposed to provide support to a transplant specialist in refining the choice of a suitable donor.

• MeSH
• algoritmy * MeSH
• HLA antigeny imunologie   MeSH
• lidé MeSH
• receptory KIR imunologie   MeSH
• registrace MeSH
• systémy pro podporu klinického rozhodování * MeSH
• testování histokompatibility metody   MeSH
• transplantace hematopoetických kmenových buněk metody   MeSH
• výběr dárců metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Československo MeSH
• Názvy látek
• HLA antigeny MeSH
• receptory KIR MeSH

Natural killer (NK) cells play a pivotal role in the immune response against viral infections, including SARS-CoV-2. However, our understanding of memory NK cell responses in the context of SARS-CoV-2 remains limited. To address this, we investigated the memory-like response of NK cells to SARS-CoV-2 peptides, presented by autologous cells. Blood samples from 45 donors underwent analysis for SARS-CoV-2 IgG antibodies, categorizing them into four groups based on the antibody kind and level. NK cells from SARS-CoV-2-experienced donors demonstrated enhanced degranulation and activation levels, IFNγ production and proliferative potential in response to SARS-CoV-2 peptides. Investigation of highly proliferating NK cells demonstrated the formation of distinct clusters depending on the SARS-CoV-2 peptide supplementation and the donor group. RNA sequencing revealed differential gene expression patterns, highlighting metabolism, protein transport, and immune response genes. Notably, KIR2DS4 expression correlated with enhanced IFNγ production, degranulation and proliferation levels, suggesting a role in SARS-CoV-2 recognition. Collectively, these findings provide detailed insights into antigen-specific NK cell responses to SARS-CoV-2 peptides, indicating potential mechanisms underlying NK cell activation in antiviral immunity.

• Klíčová slova
• KIR2DS4, NK cells, SARS‐CoV‐2, antigen‐specific NK cells,
• MeSH
• aktivace lymfocytů MeSH
• buňky NK * imunologie   MeSH
• COVID-19 * imunologie   MeSH
• degranulace buněk MeSH
• dospělí MeSH
• imunoglobulin G MeSH
• imunologická paměť MeSH
• interferon gama * imunologie   metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• protilátky virové krev   imunologie   MeSH
• receptory KIR genetika   metabolismus   MeSH
• SARS-CoV-2 * imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• imunoglobulin G MeSH
• interferon gama * MeSH
• protilátky virové MeSH
• receptory KIR MeSH