12 research outputs found
Hidden Patterns of Anti-HLA Class I Alloreactivity Revealed Through Machine Learning
Detection of alloreactive anti-HLA antibodies is a frequent and mandatory test before and
after organ transplantation to determine the antigenic targets of the antibodies.
Nowadays, this test involves the measurement of fluorescent signals generated through
antibody–antigen reactions on multi-beads flow cytometers. In this study, in a cohort of
1,066 patients from one country, anti-HLA class I responses were analyzed on a panel of
98 different antigens. Knowing that the immune system responds typically to “shared”
antigenic targets, we studied the clustering patterns of antibody responses against HLA
class I antigens without any a priori hypothesis, applying two unsupervised machine
learning approaches. At first, the principal component analysis (PCA) projections of intralocus
specific responses showed that anti-HLA-A and anti-HLA-C were the most distantly
projected responses in the population with the anti-HLA-B responses to be projected
between them. When PCA was applied on the responses against antigens belonging to a
single locus, some already known groupings were confirmed while several new crossreactive
patterns of alloreactivity were detected. Anti-HLA-A responses projected through
PCA suggested that three cross-reactive groups accounted for about 70% of the variance
observed in the population, while anti-HLA-B responses were mainly characterized by a
distinction between previously described Bw4 and Bw6 cross-reactive groups followed
by several yet undocumented or poorly described ones. Furthermore, anti-HLA-C
responses could be explained by two major cross-reactive groups completely
overlapping with previously described C1 and C2 allelic groups. A second featurebased
analysis of all antigenic specificities, projected as a dendrogram, generated a
robust measure of allelic antigenic distances depicting bead-array defined cross reactive
groups. Finally, amino acid combinations explaining major population specific crossreactive
groups were described. The interpretation of the results was based on the current
knowledge of the antigenic targets of the antibodies as they have been characterized
either experimentally or computationally and appear at the HLA epitope registry
Patterns of 1,748 Unique Human Alloimmune Responses Seen by Simple Machine Learning Algorithms
Allele specific antibody response against the polymorphic system of HLA is the
allogeneic response marker determining the immunological risk for graft acceptance
before and after organ transplantation and therefore routinely studied during the patient’s
workup. Experimentally, bead bound antigen- antibody reactions are detected using
a special multicolor flow cytometer (Luminex). Routinely for each sample, antibody
responses against 96 different HLA antigen groups are measured simultaneously and
a 96-dimensional immune response vector is created. Under a common experimental
protocol, using unsupervised clustering algorithms, we analyzed these immune intensity
vectors of anti HLA class II responses from a dataset of 1,748 patients before or after
renal transplantation residing in a single country. Each patient contributes only one
serum sample in the analysis. A population view of linear correlations of hierarchically
ordered fluorescence intensities reveals patterns in human immune responses with
striking similarities with the previously described CREGs but also brings new information
on the antigenic properties of class II HLA molecules. The same analysis affirms that
“public” anti-DP antigenic responses are not correlated to anti DR and anti DQ responses
which tend to cluster together. Principal Component Analysis (PCA) projections also
demonstrate ordering patterns clearly differentiating anti DP responses from anti DR
and DQ on several orthogonal planes. We conclude that a computer vision of human
alloresponse by use of several dimensionality reduction algorithms rediscovers proven
patterns of immune reactivity without any a priori assumption and might prove helpful for
a more accurate definition of public immunogenic antigenic structures of HLA molecules.
Furthermore, the use of Eigen decomposition on the Immune Response generates new
hypotheses that may guide the design of more effective patient monitoring tests
Hidden Patterns of Anti-HLA Class I Alloreactivity Revealed Through Machine Learning
Detection of alloreactive anti-HLA antibodies is a frequent and mandatory test before and
after organ transplantation to determine the antigenic targets of the antibodies.
Nowadays, this test involves the measurement of fluorescent signals generated through
antibody–antigen reactions on multi-beads flow cytometers. In this study, in a cohort of
1,066 patients from one country, anti-HLA class I responses were analyzed on a panel of
98 different antigens. Knowing that the immune system responds typically to “shared”
antigenic targets, we studied the clustering patterns of antibody responses against HLA
class I antigens without any a priori hypothesis, applying two unsupervised machine
learning approaches. At first, the principal component analysis (PCA) projections of intralocus
specific responses showed that anti-HLA-A and anti-HLA-C were the most distantly
projected responses in the population with the anti-HLA-B responses to be projected
between them. When PCA was applied on the responses against antigens belonging to a
single locus, some already known groupings were confirmed while several new crossreactive
patterns of alloreactivity were detected. Anti-HLA-A responses projected through
PCA suggested that three cross-reactive groups accounted for about 70% of the variance
observed in the population, while anti-HLA-B responses were mainly characterized by a
distinction between previously described Bw4 and Bw6 cross-reactive groups followed
by several yet undocumented or poorly described ones. Furthermore, anti-HLA-C
responses could be explained by two major cross-reactive groups completely
overlapping with previously described C1 and C2 allelic groups. A second featurebased
analysis of all antigenic specificities, projected as a dendrogram, generated a
robust measure of allelic antigenic distances depicting bead-array defined cross reactive
groups. Finally, amino acid combinations explaining major population specific crossreactive
groups were described. The interpretation of the results was based on the current
knowledge of the antigenic targets of the antibodies as they have been characterized
either experimentally or computationally and appear at the HLA epitope registry
Hidden Patterns of Anti-HLA Class I Alloreactivity Revealed Through Machine Learning
Detection of alloreactive anti-HLA antibodies is a frequent and mandatory test before and
after organ transplantation to determine the antigenic targets of the antibodies.
Nowadays, this test involves the measurement of fluorescent signals generated through
antibody–antigen reactions on multi-beads flow cytometers. In this study, in a cohort of
1,066 patients from one country, anti-HLA class I responses were analyzed on a panel of
98 different antigens. Knowing that the immune system responds typically to “shared”
antigenic targets, we studied the clustering patterns of antibody responses against HLA
class I antigens without any a priori hypothesis, applying two unsupervised machine
learning approaches. At first, the principal component analysis (PCA) projections of intralocus
specific responses showed that anti-HLA-A and anti-HLA-C were the most distantly
projected responses in the population with the anti-HLA-B responses to be projected
between them. When PCA was applied on the responses against antigens belonging to a
single locus, some already known groupings were confirmed while several new crossreactive
patterns of alloreactivity were detected. Anti-HLA-A responses projected through
PCA suggested that three cross-reactive groups accounted for about 70% of the variance
observed in the population, while anti-HLA-B responses were mainly characterized by a
distinction between previously described Bw4 and Bw6 cross-reactive groups followed
by several yet undocumented or poorly described ones. Furthermore, anti-HLA-C
responses could be explained by two major cross-reactive groups completely
overlapping with previously described C1 and C2 allelic groups. A second featurebased
analysis of all antigenic specificities, projected as a dendrogram, generated a
robust measure of allelic antigenic distances depicting bead-array defined cross reactive
groups. Finally, amino acid combinations explaining major population specific crossreactive
groups were described. The interpretation of the results was based on the current
knowledge of the antigenic targets of the antibodies as they have been characterized
either experimentally or computationally and appear at the HLA epitope registry
Potable Water Quality on Non-Passenger Ships Calling Belgian Ports
Waterborne disease due to the microbial contamination of potable water onboard ships is a potential threat for seafarers. The results from the samples collected at Belgian ports from 2010 to 2018 during inspections of non-passenger ships are used to evaluate the microbiological and chemical quality of potable water. A small proportion of the samples was found positive for indicator organisms (7.5%), indicating the lack of proper disinfection and possible contamination. Further analyses and risk assessments are recommended for examining possible contributing factors. Inspections for the issuance of SSC should focus on water safety and the prevention of waterborne diseases
Legionella spp. Colonization on Non-Passenger Ships Calling at Belgian Ports
The association of cases of Legionnaires’ disease and ships has been well documented. Results from potable water samples collected for microbiological analysis during SSC inspections conducted from 2010 to 2018 at Belgian ports were analyzed in order to evaluate the level of colonization on non-passenger ships. Results indicate a high degree of colonization (77.2% of the ships were found to be colonized with Legionella spp. at least once) and further analysis is recommended to examine possible factors associated with colonization. Inspections for issuance of SSC should focus on water safety and prevention of Legionnaires’ disease
Patterns of 1,748 Unique Human Alloimmune Responses Seen by Simple Machine Learning Algorithms
Allele specific antibody response against the polymorphic system of HLA is the
allogeneic response marker determining the immunological risk for graft acceptance
before and after organ transplantation and therefore routinely studied during the patient’s
workup. Experimentally, bead bound antigen- antibody reactions are detected using
a special multicolor flow cytometer (Luminex). Routinely for each sample, antibody
responses against 96 different HLA antigen groups are measured simultaneously and
a 96-dimensional immune response vector is created. Under a common experimental
protocol, using unsupervised clustering algorithms, we analyzed these immune intensity
vectors of anti HLA class II responses from a dataset of 1,748 patients before or after
renal transplantation residing in a single country. Each patient contributes only one
serum sample in the analysis. A population view of linear correlations of hierarchically
ordered fluorescence intensities reveals patterns in human immune responses with
striking similarities with the previously described CREGs but also brings new information
on the antigenic properties of class II HLA molecules. The same analysis affirms that
“public” anti-DP antigenic responses are not correlated to anti DR and anti DQ responses
which tend to cluster together. Principal Component Analysis (PCA) projections also
demonstrate ordering patterns clearly differentiating anti DP responses from anti DR
and DQ on several orthogonal planes. We conclude that a computer vision of human
alloresponse by use of several dimensionality reduction algorithms rediscovers proven
patterns of immune reactivity without any a priori assumption and might prove helpful for
a more accurate definition of public immunogenic antigenic structures of HLA molecules.
Furthermore, the use of Eigen decomposition on the Immune Response generates new
hypotheses that may guide the design of more effective patient monitoring tests
Patterns of 1,748 Unique Human Alloimmune Responses Seen by Simple Machine Learning Algorithms
Allele specific antibody response against the polymorphic system of HLA is the
allogeneic response marker determining the immunological risk for graft acceptance
before and after organ transplantation and therefore routinely studied during the patient’s
workup. Experimentally, bead bound antigen- antibody reactions are detected using
a special multicolor flow cytometer (Luminex). Routinely for each sample, antibody
responses against 96 different HLA antigen groups are measured simultaneously and
a 96-dimensional immune response vector is created. Under a common experimental
protocol, using unsupervised clustering algorithms, we analyzed these immune intensity
vectors of anti HLA class II responses from a dataset of 1,748 patients before or after
renal transplantation residing in a single country. Each patient contributes only one
serum sample in the analysis. A population view of linear correlations of hierarchically
ordered fluorescence intensities reveals patterns in human immune responses with
striking similarities with the previously described CREGs but also brings new information
on the antigenic properties of class II HLA molecules. The same analysis affirms that
“public” anti-DP antigenic responses are not correlated to anti DR and anti DQ responses
which tend to cluster together. Principal Component Analysis (PCA) projections also
demonstrate ordering patterns clearly differentiating anti DP responses from anti DR
and DQ on several orthogonal planes. We conclude that a computer vision of human
alloresponse by use of several dimensionality reduction algorithms rediscovers proven
patterns of immune reactivity without any a priori assumption and might prove helpful for
a more accurate definition of public immunogenic antigenic structures of HLA molecules.
Furthermore, the use of Eigen decomposition on the Immune Response generates new
hypotheses that may guide the design of more effective patient monitoring tests
Potable Water Quality on Non-Passenger Ships Calling Belgian Ports
Waterborne disease due to the microbial contamination of potable water onboard ships is a potential threat for seafarers. The results from the samples collected at Belgian ports from 2010 to 2018 during inspections of non-passenger ships are used to evaluate the microbiological and chemical quality of potable water. A small proportion of the samples was found positive for indicator organisms (7.5%), indicating the lack of proper disinfection and possible contamination. Further analyses and risk assessments are recommended for examining possible contributing factors. Inspections for the issuance of SSC should focus on water safety and the prevention of waterborne diseases
<i>Legionella</i> spp. Colonization on Non-Passenger Ships Calling at Belgian Ports
The association of cases of Legionnaires’ disease and ships has been well documented. Results from potable water samples collected for microbiological analysis during SSC inspections conducted from 2010 to 2018 at Belgian ports were analyzed in order to evaluate the level of colonization on non-passenger ships. Results indicate a high degree of colonization (77.2% of the ships were found to be colonized with Legionella spp. at least once) and further analysis is recommended to examine possible factors associated with colonization. Inspections for issuance of SSC should focus on water safety and prevention of Legionnaires’ disease