Automated serum protein electrophoresis by Capillarys

PLASMA PROTEIN ELECTROPHORESIS IN THE WHITE STORK (CICONIA CICONIA): AGREEMENT BETWEEN AGAROSE GEL VERSUS CAPILLARY ZONE METHODS AND DEVELOPMENT OF REFERENCE INTERVALS

The white stork (Ciconia ciconia) is a ciconiiform species widely represented in zoological institutions. Plasma protein electrophoresis is widely used in avian patients for assessment of inflammatory conditions, but reference intervals for this testing modality are lacking for the white stork. The two main electrophoretic methods are agarose gel electrophoresis (AGE) and capillary zone electrophoresis (CZE). This study assessed fresh plasma samples of healthy adult white storks (n = 30). Statistical analyses were performed to evaluate agreement between AGE and CZE. Typical electrophoretic fractions were obtained from both methods (prealbumin, albumin, α1, α2, β, γ1, and γ2). The AGE and CZE methods were not equivalent for determining major electrophoretic fractions (except β-globulins) and albumin:globulin ratio on plasma samples. An additional prealbumin fraction was seen with CZE. Reference intervals were established for each method as the smallest n group was 27 individuals for a given value; most values had normal distribution, and robust or parametric methods were used on the data.

Development of an Online Isotope Dilution CE/ICP-MS Method for the Quantification of Sulfur in Biological Compounds

We report an analytical methodology for the quantification of sulfur in biological molecules via a species-unspecific postcolumn isotope dilution (online ID) approach using capillary electrophoresis (CE) coupled online with inductively coupled plasma-mass spectrometry (online ID CE/ICP-MS). The method was optimized using a mixture of standard compounds including sulfate, methionine, cysteine, cystine, and albumin, yielding compound recoveries between 98 and 105%. The quantity of sulfur is further converted to the quantity of the compounds owing to the prior knowledge of the sulfur content in the molecules. The limit of detection and limit of quantification of sulfur in the compounds were 1.3-2.6 and 4.1-8.4 mg L-1, respectively, with a correlation coefficient of 0.99 within the concentration range of sulfur of 5-100 mg L-1. The capability of the method was extended to quantify albumin in its native matrix (i.e., in serum) using experimentally prepared serum spiked with a pure albumin standard for validation. The relative expanded uncertainty of the method for the quantification of albumin was 6.7% (k = 2). Finally, we tested the applicability of the method on real samples by the analysis of albumin in bovine and human sera. For automated data assessment, a software application (IsoCor)─which was developed by us in a previous work─was developed further for handling of online ID data. The method has several improvements compared to previously published setups: (i) reduced adsorption of proteins onto the capillary wall owing to a special capillary-coating procedure, (ii) baseline separation of the compounds in less than 30 min via CE, (iii) quantification of several sulfur species within one run by means of the online setup, (iv) SI traceability of the quantification results through online ID, and (v) facilitated data processing of the transient signals using the IsoCor application. Our method can be used as an accurate approach for quantification of proteins and other biological molecules via sulfur analysis in complex matrices for various fields, such as environmental, biological, and pharmaceutical studies as well as clinical diagnosis.

Effects of lipemia on capillary serum protein electrophoresis in native ultra-lipemic material and intravenous lipid emulsion added sera

OBJECTIVES

This study aims to investigate the effect of natural ultralipemic material (NULM) and intravenous lipid emulsion (IVLE) on capillary serum protein electrophoresis (SPEP).

METHODS

NULM material was prepared from leftover patients' lipemic serum sample (triglyceride concentration >2,000 mg/dL) pool by a refrigerated high-speed centrifuge, and IVLE Omegaven lipid emulsion (30%) was used. Serum pools for interference study were prepared from patient samples for which serum protein electrophoresis was studied as Normal SPEP and M Peak SPEP. For both types of lipemia (DULM and IVLE), five pools with triglyceride concentrations of ∼4.52 mmol/L, ∼7.91 mmol/L, ∼14.69 mmol/L, ∼21.47 mmol/L, and ∼28.25 mmol/L were prepared. SPEP was studied in each pool with Sebia Capillarys Minicap. A repeated measure ANOVA test was used to determine the difference between the pools, and interferograms were used to evaluate the interference effect.

RESULTS

Interference was not detected in IVLE added Normal SPEP and M Peak SPEP pools, either % or concentrations of fractions. In NULM-added Normal SPEP and M Peak SPEP pools, significant positive interference in albumin % (p=0.002 and p<0.001 respectively) and significant negative interference in gamma% (p<0.001 and p=0.005 respectively) and M protein peak (p=0.002) fractions were detected. However, significant positive interference was seen only for albumin concentration fractions (p<0.001 for both pools).

CONCLUSIONS

It is vital to use NULM instead of IVLE solutions in lipemia interference studies for all laboratory tests, including CZE SPEP. The fractions concentration values calculated with the total protein concentration should be used for evaluating SPEP results.

Establishment of Reference Intervals for Serum Protein Electrophoresis of Apparently Healthy Adults in Addis Ababa, Ethiopia

Background

Even though several factors affect reference intervals (RIs), company-derived values are currently in use in many laboratories worldwide. However, few or no data are available regarding serum proteins RIs, especially in resource-limited countries such as Ethiopia.

Objective

To establish RIs for serum protein electrophoresis of apparently healthy adults in Addis Ababa, Ethiopia.

Methods

A cross-sectional study was conducted on a total of 297 apparently healthy adults from April to October 2019 in four selected sub-cities (Akaki, Kirkos, Arada, and Yeka) of Addis Ababa, Ethiopia. Laboratory analysis of collected samples was performed using the Capillarys 2 Flex Piercing analyzer, while statistical analysis was conducted using SPSS version 23 and Med-Calc software. The Mann-Whitney test was used to check partitions. A non-parametric method of reference range establishment was performed as per CLSI guideline EP28A3C.

Results

The established RIs were: albumin 53.83-64.59%, 52.24-63.55%; alpha-1 globulin 3.04-5.40%, 3.44-5.60%; alpha-2 globulin 8.0-12.67%, 8.44-12.87%; and beta-1 globulin 5.01-7.38%, 5.14-7.86%. Moreover, the albumin to globulin ratios were 1.16-1.8 and 1.09-1.74 for males and females, respectively. The combined RIs for beta-2 globulin and gamma globulin were 2.54-4.90% and 12.40-21.66%, respectively.

Conclusion

The established reference interval for serum protein fractions revealed gender-specific differences, except for beta-2 globulin and gamma globulin.

Effect of Different Levels of Multienzymes on Immune Response, Blood Hematology and Biochemistry, Antioxidants Status and Organs Histology of Broiler Chicks Fed Standard and Low-Density Diets

This study was executed to investigate the effect of supplementing three multienzyme levels (0, 0. 1, and 0.2%) with two types of diet [standard diet (SD) vs. low-density diet (LDD)] on immune response, blood hematology and biochemistry, antioxidant status, and organ histology of broilers during 1–38 days of age. A total of 216 unsexed 1-day-old Arbor Acres broiler chicks were randomly distributed, on a factorial design (2 × 3), to six treatments each with six replicates. There were six chicks per replicate. Results showed that LDD significantly decreased body weight gain (BWG) of broilers, but did not affect the European Production Efficiency Index (EPEI). Addition of multienzymes at both levels (0.1 and 0.2%) significantly increased BWG and improved EPEI, compared to the control diet. Alanine aminotransferase (ALT), aspirate aminotransferase (AST), malondialdehyde (MDA), lymphocyte, lymphocyte transformation test (LTT), and phagocyte activity (PA) were significantly higher for LDD than the SD, but eosinophil was lower. Supplementation of multienzymes significantly decreased ALT, AST, and MDA, compared to the control group, but increased packed cell volume (PCV), hemoglobin (Hgb), lymphocytes, and monocytes. Immune organs, such as spleen, thymus, and the bursa of Fabricius were significantly increased with multienzyme supplementation. It could be concluded that multienzyme supplementation at either 0.1 or 0.2% to SD or LDD improved EPEI and immune status of broiler chicks.

Plasma protein fractions in free-living white-tailed eagle (Haliaeetus albicilla) nestlings from Norway

BACKGROUND

Capillary electrophoresis of plasma proteins has shown great potential as a complementary diagnostic tool for avian species. However, reference intervals for plasma proteins are sparse or lacking for several free-living avian species. The current study reports electrophoretic patterns and concentrations of plasma proteins determined for 70 free-living white-tailed eagle (Haliaeetus albicilla) nestlings from two locations in Norway (Steigen and Smøla) in order to establish reference values for this subpopulation using capillary electrophoresis. The nestlings were between 44 and 87 days of age, and the plasma protein concentrations were investigated for age, sex, year (2015 and 2016) and location differences. To our knowledge, this is the first report of reference intervals of plasma proteins analysed by capillary electrophoresis in free-living white-tailed eagle nestlings.

RESULTS

The plasma protein concentrations (% of total protein, mean ± SE) were determined for prealbumin (13.7%, 4.34 ± 0.15 g/L), albumin (46.7%, 14.81 ± 0.24 g/L), α₁-globulin (2.4%, 0.74 ± 0.03 g/L), α₂-globulin (11.7%, 3.72 ± 0.06 g/L), β-globulin (15.9%, 5.06 ± 0.08 g/L) and γ-globulin (9.6%, 3.05 ± 0.09 g/L). Significant differences were found between the two locations for prealbumin, α₂- and γ-globulins. No significant differences were found between the two sampling years or sexes, and no effect of age was found for any of the plasma proteins. However, prealbumin levels were several folds higher than previously reported from adults of closely related birds of prey species. There were no other studies on capillary electrophoresis of nestling plasma available for comparison.

CONCLUSION

Significant differences were found between sampling locations for prealbumin, α₂- and γ-globulins, which may indicate differences in inflammatory or infectious status between nestlings at the two locations. Sampling year, sex or age had no significant effect on the plasma protein concentrations. These results provide novel data on plasma protein concentrations by capillary electrophoresis and may be useful for evaluation of health status in free-living white-tailed eagle nestlings.

Protein characterization using electrophoresis and immunofixation; a case-based review of dogs and cats

Protein electrophoresis and immunotyping can be a useful adjunct to the standard biochemical techniques for characterizing serum and urine proteins. This paper reviews currently available and commonly used methods for diagnostic protein electrophoresis, including both agarose gel and capillary zone electrophoretic techniques and total protein assessments. Immunofixation and immunosubtraction methods for identification of immunoglobulin location and class are also presented. Practical application of quality assurance and quality control strategies in compliance with American Society of Veterinary Clinical Pathology (ASVCP) best practices are discussed. Commonly encountered serum and urine electrophoretic diagnostic patterns, including electrophoretically normal, acute-phase protein responses, polyclonal gammopathies, restricted polyclonal/oligoclonal gammopathies, paraproteinemias (monoclonal or biclonal gammopathies), and Bence-Jones proteinurias are also reviewed using relevant case material. Cases in which immunofixation electrophoresis are particularly useful are highlighted, and methodologies to more accurately quantify serum monoclonal proteins (M-proteins), monitoring tests commonly used in human medicine, are discussed.

Prognostic value of cryoglobulins, protein electrophoresis, and serum immunoglobulins for lymphoma development in patients with Sjögren's syndrome. A retrospective cohort study

BACKGROUND

Patients with Sjögren's syndrome (SS) have a considerable higher risk of lymphoma development.

OBJECTIVES

To determine the incidence of lymphoma and the value of biomarkers to predict lymphoma development in patients with SS.

METHODS

Clinical files of all patients with a presumed diagnosis of SS between 1991 and 2016 were retrospectively reviewed for the development of lymphoma. Biochemical data were plotted as a function of the relative time before and after the lymphoma diagnosis (for patients who developed lymphoma) or before the last available blood test (for patients who did not develop lymphoma). Correlations between several biochemical parameters and development of lymphoma were analyzed by logistic regression. In order to evaluate the evolution of cryoglobulins, a random effect model with random intercepts was used.

RESULTS

Sixteen patients developed a lymphoma (prevalence 8.9%; median follow-up 6 years). Cryoglobulins were significantly higher in these patients (n = 16), when compared to the rest of patients (n = 164) without lymphoma (121 ± 250 versus 8 ± 24.9 mg/L for IgG; 231 ± 422 versus 13 ± 30 mg/L for IgM; 10 ± 20 versus 1 ± 4 mg/L for IgA in the cryoprecipitate). Cryoglobulin-levels were significantly more increasing (p-values for IgG = 0.0007; for IgM = 0.0123; and for IgA in the cryoprecipitate <0.0001) in the time period before the lymphoma diagnosis (patients with lymphoma) compared to the time period before the last available blood test (patients without lymphoma). Also low (i.e. under the detection limit) C3 (OR 13.9) or C4 (OR 7.1) levels, a progressively decreasing total complement activity (OR 6.6), progressively decreasing gammaglobulins (OR 13.4), a persistent detection of monoclonal bands (OR 14.6) on protein electrophoresis, a persistent low or decreasing serum IgG (OR 18), and decreasing IgM-serum levels (OR 17.7) were significantly associated with lymphoma.

CONCLUSION

Periodically follow-up of laboratory markers, such as cryogloblins, over time proved to be an accurate way to predict lymphoma.

Detection of hereditary bisalbuminemia in bottlenose dolphins (Tursiops truncatus, Montagu 1821): comparison between capillary zone and agarose gel electrophoresis

Background

Hereditary bisalbuminemia is a relatively rare anomaly characterized by the occurrence of two albumin fractions on serum protein separation by electrophoresis. In human medicine, it is usually revealed by chance, is not been clearly associated with a specific disease and the causative genetic alteration is a point mutation of human serum albumin gene inherited in an autosomal codominant pattern. This type of alteration is well recognizable by capillary zone electrophoresis (CZE), whilst agarose gel electrophoresis (AGE) not always produces a clear separation of albumin fractions. The aims of this study is to report the presence of this abnormality in two separate groups of related bottlenose dolphins and to compare the results obtained with capillary zone and agarose gel electrophoresis.

Results

Serum samples from 40 bottlenose dolphins kept under human care were analyzed. In 9 samples a double albumin peak was evident in CZE electrophoresis while no double peak was noted in AGE profile. Since only an apparently wider albumin peaks were noted in some AGE electrophoretic profiles, the ratio between base and height (b/h) of the albumin peak was calculated and each point-value recorded in the whole set of data was used to calculate a receiver operating characteristic curve: when the b/h ratio of albumin peak was equal or higher than 0.25, the sensitivity and specificity of AGE to detect bisalbuminemic samples were 87 and 63 %, respectively. The bisalbuminemic dolphins belong to two distinct families: in the first family, all the siblings derived from the same normal sire were bisalbuminemic, whereas in the second family bisalbuminemia was present in a sire and in two out of three siblings.

Conclusions

We report for the first time the presence of hereditary bisalbuminemia in two groups of related bottlenose dolphins identified by means of CZE and we confirm that AGE could fail in the identification of this alteration.

Inability to Measure M-Protein With Capillary Zone Electrophoresis (CAPPILLARYS 2) in Tracings With NonDiscernable Peaks

BACKGROUND

We performed a retrospective study to illustrate the challenges with quantifying monoclonal (M)-protein in the cases of serum protein capillary zone electrophoresis (SPCZE) where no discernable peak is apparent.

MATERIALS AND METHODS

We retrospectively reviewed 160 serum immunofixation electrophoresis (SIFE) that were performed at Memorial Hermann Hospital-Texas Medical Center between October 2013 and November 2013 and we identified the positive SIFE results. The corresponding SPCZE of the positive SIFE were retrieved and evaluated for the ability to quantify M-proteins in them. We define the ability to quantify M-protein as the ability for the operator of the SPCZE to identify a discernable peak and to be able to manually gate the area under the peak.

RESULTS

Twenty-two cases of SIFE detected a monoclonal immunoglobulin. Of the corresponding 22 SPCZE, we could not quantify the M-protein in 6 (27.3%) of the cases.

CONCLUSION

We have shown several cases where we were not able to quantify the M-protein with SPCZE. This poses a challenge in the diagnosis and management of these patients.

High false-positive rate for monoclonal gammopathy using capillary electrophoresis (CAPILLARYS 2) alone

BACKGROUND

Capillary zone electrophoresis (CZE) is a newer method of performing serum protein electrophoresis and is considered to be faster and more efficient than agarose gel method. We decided to evaluate CZE as an efficient screening tool for monoclonal gammopathies, and we began recommending immunofixation studies in cases with such minor/subtle distortions to avoid missing monoclonal gammopathies.

METHODS

We evaluated 163 serum protein agarose gel electrophoresis (SPAGE) samples between October and November 2011, and 447 serum protein CZE (SPCZE) samples between January 2012 to February 2012 and August 2012 to September 2012.

RESULTS

Immunofixation studies were recommended in 51 of 163 cases (31.3%) performed by SPAGE, and in 274 of 447 cases (61.3%) performed by SPCZE. While using SPAGE, of the 51 cases recommended for immunofixation (24 were performed to date), six cases (25.0%) were positive for monoclonal gammopathy. In contrast, while using SPCZE, of the 274 cases recommended for immunofixation (118 were performed to date), 18 cases (15.2%) were positive for monoclonal gammopathy. Using the SPCZE method, of these 18 cases, five (27.8%) had minor/subtle distortions without obvious peaks. Our recommendation rate for immunofixation studies has thus almost doubled (61.3% vs. 31.3%) with the adoption of SPCZE. Yet, using SPCZE has not translated to detecting more cases of true monoclonal gammopathies.

CONCLUSION

Therefore, we conclude that there is a high false-positive rate for monoclonal gammopathy using CE alone.

Plasma protein electrophoresis in birds: comparison of a semiautomated agarose gel system with an automated capillary system

Plasma agarose gel electrophoresis (AGE) is recognized as a very reliable diagnostic tool in avian medicine. Within the last 10 years, new electrophoresis techniques such as capillary zone electrophoresis (CZE) have emerged in human laboratory medicine but have never been investigated in birds. To investigate the use of CZE in birds and to compare it with AGE, plasma samples from 30 roosters (Gallus gallus), 20 black kites (Milvus migrans), and 10 racing pigeons (Columba livia) were analyzed by both AGE and CZE. For the 3 species studied, values determined by AGE and CZE were well correlated for albumin and beta and gamma fractions whereas other values differed significantly. Values for alpha-3 fraction in the rooster, alpha-1 fraction in the black kite, and alpha fractions in the pigeon obtained by AGE were very well correlated with the prealbumin fraction values obtained by CZE. Repeatability and reproducibility appeared higher with CZE than with AGE. Although the interpretation of CZE electrophoresis patterns seems to produce results similar to those obtained with AGE, some proteins present in the alpha fraction measured with AGE migrated to the prealbumin fraction found with CZE. Although CZE requires the use of specific reference intervals and a much higher sample volume, this method has many advantages when compared with AGE, including better repeatability and reproducibility and higher analysis output.

Transferrin polymorphism and opportunistic infections in HIV-infected women in Rwanda

OBJECTIVE

We investigated the prevalence of opportunistic infections in HIV-infected women according to transferrin (TF) phenotype.

METHODS

We conducted a cross-sectional study among 200 HIV-positive women in the Butare University Teaching Hospital in Rwanda. TF phenotypes were determined using starch gel electrophoresis.

RESULTS

Phenotype frequencies of TF CD, CB and CC were 14.5, 3 and 82.5%, respectively. The homozygous TF DD phenotype was not found. Subjects with TF CD phenotype had a significantly higher prevalence of opportunistic infections than subjects with TF CC phenotype, 76 and 52%, respectively (p = 0.026). In logistic regression, there was a significant correlation between TF phenotypes and opportunistic infections (p = 0.012). Subjects with TF CD phenotype had significantly lower values for TF (p = 0.006) than TF CC subjects. Hematological parameters (RBC, RBC indices, hemoglobin, hematocrit, WBC, neutrophils, lymphocytes, platelets and erythrocyte sedimentation rate), iron, ferritin, TF saturation, C-reactive protein and CD4 count did not differ according to TF phenotype.

CONCLUSION

Subjects with TF CC phenotype have a lower prevalence of opportunistic infections. Iron status may play a role in this association.

Human complement factor 3 polymorphism determination by capillary electrophoresis of serum

Variability of complement factor 3 (C3) mobility in serum protein electrophoresis was investigated. We found that the migration time of C3 can be reproducibly determined (beween-run CV=0.76%) using clinical capillary electrophoresis (CE) equipment (the Capillarys™ 2 system, Sebia). Moreover, we found a significant difference (p<0.001) in migration times of the major C3 phenotypes FF (fast-fast), FS (fast-slow) and SS (slow-slow). Glycosylation did not significantly affect test results. This is the first report on the migration time of C3 phenotypes on a clinical CE instrument. The presented method allows faster data than agarose-electrophoresis or genotyping. Moreover, reference ranges for serum C3 concentration depend on C3 phenotype, which allows a better tailored clinical interpretation of C3 concentrations.

Performance of the Sebia CAPILLARYS 2 for detection and immunotyping of serum monoclonal paraproteins

We evaluated the performance of the CAPILLARYS 2 (Sebia, Norcross, GA) capillary electrophoresis system for detection and identification of monoclonal proteins in serum samples. We analyzed 104 serum specimens by Sebia Hydragel serum protein electrophoresis (agarose gel electrophoresis [AGE]/immunofixation electrophoresis [IFE]) and CAPILLARYS 2 capillary zone electrophoresis (CZE)/immunosubtraction. AGE and CZE had sensitivities of 90% and 81%, respectively, based on IFE as the "gold standard," and all bands detected were confirmed by IFE (100% specificity). AGE and CZE had an overall agreement of 91% on serum protein electrophoresis. In the population tested, IgG was detected in 29% of samples by IFE and 30% using immunosubtraction. Similarly IgA was detected in 9% of cases by IFE and 8% by immunosubtraction. IgM and light chains were detected in 6% and 3% of cases, respectively, by IFE, whereas CZE/immunosubtraction did not detect any IgM or light chains. In our hands, AGE and CZE had the same specificity for detection of monoclonal proteins; however, CZE/immunosubtraction seems to be less sensitive than IFE for the detection of IgM and, possibly, serum light chains.

Separation of serum proteins by automated capillary zone electrophoresis

Capillary zone electrophoresis (CZE) of serum proteins is increasingly gaining impact in clinical laboratories. Two automated multichannel instruments dedicated to the separation of serum proteins have become available over the last 6 years, the Paragon CZE 2000 (Beckman Coulter, CA, USA) and, more recently, the Capillarys (Sebia, France). This review focuses on the performance of these commercial instruments to separate serum proteins in a clinical laboratory setting. The utility of CZE to recognize various dysproteinemias and to detect and identify monoclonal proteins will be described and systematically reviewed. The reader will be provided with a summation and an understanding of CZE-specific interference.