Publications by authors named "Katherine M Kichula"

Article Synopsis
  • Genetic variation in immune responses, particularly related to HLA and KIR genes, influences how First Nations peoples are affected by infectious diseases.
  • HLA-A24:02 and the KIR3DL1 receptor have evolved in First Nations populations, showcasing a significant adaptation through natural selection.
  • The KIR3DL1114 allele, unique to Oceania, demonstrates a strong interaction with HLA-A24:02, which enhances immune response, thus highlighting the importance of immunogenetic studies in understanding disease susceptibility.
View Article and Find Full Text PDF
Article Synopsis
  • KIR interactions with HLA class I are important for NK cell responses to viruses, including SARS-CoV-2.
  • In a study comparing COVID-19 patients to a control group, a higher frequency of the KIR3DL3*00802 gene variant was found in those with COVID-19, suggesting a link to increased susceptibility.
  • Conversely, the HLA-Bw4 variant, which interacts with KIR3DL1, was less frequent in COVID-19 patients, indicating it might offer some protection against the virus.
View Article and Find Full Text PDF

Introduction: Genetic predisposition to autoimmune encephalitis with antibodies against N-methyl-D-aspartate receptor (NMDAR) is poorly understood. Given the diversity of associated environmental factors (tumors, infections), we hypothesized that human leukocyte antigen () and killer-cell immunoglobulin-like receptors (), two extremely polymorphic gene complexes key to the immune system, might be relevant for the genetic predisposition to anti-NMDAR encephalitis. Notably, KIR are chiefly expressed by Natural Killer (NK) cells, recognize distinct HLA class I allotypes and play a major role in anti-tumor and anti-infection responses.

View Article and Find Full Text PDF
Article Synopsis
  • Genetic and non-genetic factors like graft-versus-host disease and viral infections significantly impact immune reconstitution after hematopoietic stem cell transplantation (HSCT).
  • A study of 54 HSCT recipients revealed a noticeable decrease in T-cell receptor (TCR) diversity over time, linked to cytomegalovirus (CMV) reactivation, which altered TCR composition and clonality.
  • CMV reactivation led to changes in natural killer (NK) cell populations, increasing certain types while decreasing others, suggesting CMV may promote the growth of specific T and NK cells to help establish a new immune repertoire.
View Article and Find Full Text PDF
Article Synopsis
  • * Currently, about 20% of the combined haplotypes from Europe are represented, but many common and rare haplotypes, particularly those associated with certain diseases, are still lacking from the global sample.
  • * The workshop is now seeking DNA samples from diverse populations, especially non-Europeans, resulting in 537 individuals contributing 294 distinct haplotypes, but still highlighting the need for more representation, particularly from African populations.
View Article and Find Full Text PDF
Article Synopsis
  • * In a study of three Chinese ethnic minority populations (She, Yugur, Tajik) compared to the majority Zhejiang Han (Zhe), the Tajik were found to have the most diverse KIR gene profiles, resembling Iranian populations more closely.
  • * The research also highlighted unique KIR gene distributions among the populations, with specific interactions influenced by demographic and evolutionary factors, providing important insights for future medical applications.
View Article and Find Full Text PDF
Article Synopsis
  • Established KIR clinical assessment algorithms for selecting donors in hematopoietic progenitor cell transplantation (HPCT) focus mainly on the gene content of KIR, while the impact of KIR allelic polymorphism remains less understood.
  • This study analyzed the effects of specific KIR2DL1 alleles (particularly polymorphic residues at codons 114 and 245) on post-transplant outcomes in a cohort of 86 acute myelogenous leukemia patients undergoing T cell depleted reduced intensity conditioning HPCT.
  • The findings revealed that KIR2DL1*003 positive donors significantly worsened 5-year overall survival and disease-free survival rates, while also increasing relapse incidence compared to KIR2DL1*003 negative donors
View Article and Find Full Text PDF
Article Synopsis
  • The study explores how variations in HLA and KIR genes influence immune responses and COVID-19 severity, analyzing data from 403 non-hospitalized and 1575 hospitalized patients in Italy.
  • A specific KIR gene variant (KIR2DS4*001) is linked to an increased risk of severe COVID-19, particularly in individuals who have two copies of this variant, while the HLA variant HLA-DPB1*13:01 appears to offer protective effects against severe disease.
  • The research finds a connection between autoantibodies against interferon-alpha and COVID-19 severity, with certain genetic markers influencing the presence of these antibodies, indicating that genetic polymorphism plays a critical role
View Article and Find Full Text PDF

Genetically determined variation of killer cell immunoglobulin like receptors (KIR) and their HLA class I ligands affects multiple aspects of human health. Their extreme diversity is generated through complex interplay of natural selection for pathogen resistance and reproductive health, combined with demographic structure and dispersal. Despite significant importance to multiple health conditions of differential effect across populations, the nature and extent of immunogenetic diversity is under-studied for many geographic regions.

View Article and Find Full Text PDF

The functionality of natural killer (NK) cells is tuned during education and is associated with remodeling of the lysosomal compartment. We hypothesized that genetic variation in killer cell immunoglobulin-like receptor (KIR) and HLA, which is known to influence the functional strength of NK cells, fine-tunes the payload of effector molecules stored in secretory lysosomes. To address this possibility, we performed a high-resolution analysis of KIR and HLA class I genes in 365 blood donors and linked genotypes to granzyme B loading and functional phenotypes.

View Article and Find Full Text PDF

Accurate and comprehensive immunogenetic reference panels are key to the successful implementation of population-scale immunogenomics. The 5Mbp Major Histocompatibility Complex (MHC) is the most polymorphic region of the human genome and associated with multiple immune-mediated diseases, transplant matching and therapy responses. Analysis of MHC genetic variation is severely complicated by complex patterns of sequence variation, linkage disequilibrium and a lack of fully resolved MHC reference haplotypes, increasing the risk of spurious findings on analyzing this medically important region.

View Article and Find Full Text PDF

Highly polymorphic interaction of KIR3DL1 and KIR3DS1 with HLA class I ligands modulates the effector functions of natural killer (NK) cells and some T cells. This genetically determined diversity affects severity of infections, immune-mediated diseases, and some cancers, and impacts the course of immunotherapies, including transplantation. KIR3DL1 is an inhibitory receptor, and KIR3DS1 is an activating receptor encoded by the KIR3DL1/S1 gene that has more than 200 diverse and divergent alleles.

View Article and Find Full Text PDF
Article Synopsis
  • * Researchers found that Zhejiang Han individuals exhibit a high frequency of specific HLA ligands and inhibitory KIR haplotypes associated with protection against infections and certain cancers compared to other populations.
  • * The findings highlight greater diversity in inhibitory KIR as opposed to activating KIR, with notable gene copy number variations and unique haplotypes that may indicate evolutionary responses to infectious diseases.
View Article and Find Full Text PDF

Killer cell immunoglobulin-like receptors (KIRs) interact with polymorphic human leucocyte antigen (HLA) class I molecules, modulating natural killer (NK) cell functions and affecting both the susceptibility and outcome of immune-mediated diseases. The KIR locus is highly diverse in gene content, copy number and allelic polymorphism within individuals and across geographical populations. To analyse currently under-represented Asian and Pacific populations, we investigated the combinatorial diversity of KIR and HLA class I in 92 unrelated Malay and 75 Malaysian Chinese individuals from the Malay Peninsula.

View Article and Find Full Text PDF

Natural killer (NK) cell functions are modulated by polymorphic killer cell immunoglobulin-like receptors (KIR). Among 13 human genes, which vary by presence and copy number, is ubiquitously present in every individual across diverse populations. No ligand or function is known for KIR3DL3, but limited knowledge of expression suggests involvement in reproduction, likely during placentation.

View Article and Find Full Text PDF