Full spectrum flow cytometry and mass cytometry: A 32-marker panel comparison.

High-dimensional single-cell data has become an important tool in unraveling the complexity of the immune system and its involvement in homeostasis and a large array of pathologies. As technological tools are developed, researchers are adopting them to answer increasingly complex biological questions. Up until recently, mass cytometry (MC) has been the main technology employed in cytometric assays requiring more than 29 markers.

cyCombine allows for robust integration of single-cell cytometry datasets within and across technologies.

Combining single-cell cytometry datasets increases the analytical flexibility and the statistical power of data analyses. However, in many cases the full potential of co-analyses is not reached due to technical variance between data from different experimental batches. Here, we present cyCombine, a method to robustly integrate cytometry data from different batches, experiments, or even different experimental techniques, such as CITE-seq, flow cytometry, and mass cytometry.

Vi-Vaccinations Induce Heterogeneous Plasma Cell Responses That Associate With Protection From Typhoid Fever.

Vi-polysaccharide conjugate vaccines are efficacious against cases of typhoid fever; however, an absolute correlate of protection is not established. In this study, we investigated the leukocyte response to a Vi-tetanus toxoid conjugate vaccine (Vi-TT) in comparison with a plain polysaccharide vaccine (Vi-PS) in healthy adults subsequently challenged with Typhi. Immunological responses and their association with challenge outcome was assessed by mass cytometry and Vi-ELISpot assay.

Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition).

These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells.

Reversal of epigenetic aging and immunosenescent trends in humans.

Epigenetic "clocks" can now surpass chronological age in accuracy for estimating biological age. Here, we use four such age estimators to show that epigenetic aging can be reversed in humans. Using a protocol intended to regenerate the thymus, we observed protective immunological changes, improved risk indices for many age-related diseases, and a mean epigenetic age approximately 1.

A clinically meaningful metric of immune age derived from high-dimensional longitudinal monitoring.

Immune responses generally decline with age. However, the dynamics of this process at the individual level have not been characterized, hindering quantification of an individual's immune age. Here, we use multiple 'omics' technologies to capture population- and individual-level changes in the human immune system of 135 healthy adult individuals of different ages sampled longitudinally over a nine-year period.

The anatomy of single cell mass cytometry data.

Mass cytometry enables the measurement of up to 50 features on single cell. This has catalyzed a shift toward multidimensional data analysis methods, rather than the manual gating strategies as traditionally for in flow cytometry data. This shift means that data scientists are involved in the analysis process to an increasing degree.

Comparison of CyTOF assays across sites: Results of a six-center pilot study.

For more than five years, high-dimensional mass cytometry has been employed to study immunology. However, these studies have typically been performed in one laboratory on one or few instruments. We present the results of a six-center study using healthy control human peripheral blood mononuclear cells (PBMCs) and commercially available reagents to test the intra-site and inter-site variation of mass cytometers and operators.

Multiparameter Phenotyping of Human PBMCs Using Mass Cytometry.

The standard for single-cell analysis of phenotype and function in recent decades has been fluorescence flow cytometry. Mass cytometry is a newer technology that uses heavy metal ions, rather than fluorochromes, as labels for probes such as antibodies. The binding of these ion-labeled probes to cells is quantitated by mass spectrometry.

Platinum-conjugated antibodies for application in mass cytometry.

Mass cytometry has overcome limitations of fluorescent single cell cytometry by allowing for the measurement of up to currently ∼40 different parameters on a single cell level. However, the cellular proteome comprises many more potential analytes, and current mass cytometry instrumentation allows for theoretically up to 121 different mass detection channels. The labeling of specific probes with appropriate metal ions is a significant hurdle for exploiting more of mass cytometry's analytical capacity.

Computationally efficient multidimensional analysis of complex flow cytometry data using second order polynomial histograms.

Many methods have been described for automated clustering analysis of complex flow cytometry data, but so far the goal to efficiently estimate multivariate densities and their modes for a moderate number of dimensions and potentially millions of data points has not been attained. We have devised a novel approach to describing modes using second order polynomial histogram estimators (SOPHE). The method divides the data into multivariate bins and determines the shape of the data in each bin based on second order polynomials, which is an efficient computation.

Barcoding of live human peripheral blood mononuclear cells for multiplexed mass cytometry.

Mass cytometry is developing as a means of multiparametric single-cell analysis. In this study, we present an approach to barcoding separate live human PBMC samples for combined preparation and acquisition on a cytometry by time of flight instrument. Using six different anti-CD45 Ab conjugates labeled with Pd104, Pd106, Pd108, Pd110, In113, and In115, respectively, we barcoded up to 20 samples with unique combinations of exactly three different CD45 Ab tags.

Phenotyping of Live Human PBMC using CyTOF™ Mass Cytometry.

Single-cell analysis has become an method of importance in immunology. Fluorescence flow cytometry has been a major player. However, due to issues such as autofluorescence and emission spillover between different fluorophores, alternative techniques are being developed.

The Split Virus Influenza Vaccine rapidly activates immune cells through Fcγ receptors.

Seasonal influenza vaccination is one of the most common medical procedures and yet the extent to which it activates the immune system beyond inducing antibody production is not well understood. In the United States, the most prevalent formulations of the vaccine consist of degraded or "split" viral particles distributed without any adjuvants. Based on previous reports we sought to determine whether the split influenza vaccine activates innate immune receptors-specifically Toll-like receptors.

Genetic and environmental determinants of human NK cell diversity revealed by mass cytometry.

Natural killer (NK) cells play critical roles in immune defense and reproduction, yet remain the most poorly understood major lymphocyte population. Because their activation is controlled by a variety of combinatorially expressed activating and inhibitory receptors, NK cell diversity and function are closely linked. To provide an unprecedented understanding of NK cell repertoire diversity, we used mass cytometry to simultaneously analyze 37 parameters, including 28 NK cell receptors, on peripheral blood NK cells from 5 sets of monozygotic twins and 12 unrelated donors of defined human leukocyte antigen (HLA) and killer cell immunoglobulin-like receptor (KIR) genotype.

Mass cytometry: protocol for daily tuning and running cell samples on a CyTOF mass cytometer.

In recent years, the rapid analysis of single cells has commonly been performed using flow cytometry and fluorescently-labeled antibodies. However, the issue of spectral overlap of fluorophore emissions has limited the number of simultaneous probes. In contrast, the new CyTOF mass cytometer by DVS Sciences couples a liquid single-cell introduction system to an ICP-MS.

Development of mass cytometry methods for bacterial discrimination.

Fluorescent flow cytometry has become the method of choice for interrogation of bacterial populations at the single-cell level. However, limitations of this technique include issues of dynamic range, spectral overlap, photobleaching, and overall low signal intensity due to the small size of bacteria. The recent development of mass cytometry allows single-cell analysis with the resolution of inductively coupled plasma mass spectrometry, facilitating multiparametric analysis.

ICP-MS-based multiplex profiling of glycoproteins using lectins conjugated to lanthanide-chelating polymers.

Lectins have been increasingly important in the study of glycoproteins. Here, we report a glycoprofiling method based on the covalent attachment of metal-chelating polymers to lectins for use in an ICP-MS-based assay. The labeled lectins are able to distinguish between glycoproteins covalently attached to a microtiter plate and their binding can be directly quantified by ICP-MS.

Glycosyltransferases involved in biosynthesis of the outer core region of Escherichia coli lipopolysaccharides exhibit broader substrate specificities than is predicted from lipopolysaccharide structures.

The waaJ, waaT, and waaR genes encode alpha-1,2-glycosyltransferases involved in synthesis of the outer core region of the lipopolysaccharide of Escherichia coli. They belong to the glycosyltransferase CAZy family 8, characterized by the GT-A fold, DXD motifs, and by retention of configuration at the anomeric carbon of the donor sugar. Each enzyme adds a hexose residue at the same stage of core oligosaccharide backbone extension.

The C-terminal Domain of the Escherichia coli WaaJ glycosyltransferase is important for catalytic activity and membrane association.

The waaJ gene encodes an alpha-1,2-glucosyltransferase involved in the synthesis of the outer core region of the lipopolysaccha-ride of some Escherichia coli and Salmonella isolates. WaaJ belongs to glycosyltransferase CAZy family 8, characterized by the GT-A fold, a DXD motif, and by retention of configuration at the anomeric carbon of the donor sugar. Detailed kinetic and structural information for bacterial family 8 glycosyltransferases has resulted from studies of Neisseria meningitidis LgtC.