| 1. |
- Bergman, Daniel, et al.
(författare)
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Pre-existing canine anti-IgG antibodies: implications for immunotherapy, immunogenicity testing and immunoassay analysis
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- One of the most enigmatic features of humoral immunity is the prevalent presence of circulating autoantibodies against IgG. These autoantibodies consist of several subsets, including rheumatoid factors, anti-Fab/anti-F(ab′)2-autoantibodies, and anti-idiotypic antibodies. Anti-IgG autoantibodies can impair the safety and efficacy of therapeutic antibodies and interfere with immunogenicity tests in clinical trials. They can also cross-react with allospecific IgG, presenting as heterophilic antibodies that interfere with diagnostic immunoassays. Owing to these factors, recent years have seen a resurgent interest in anti-IgG autoantibodies, but their underlying clinical significance, as well as biological roles and origins, remain opaque. Increased knowledge about canine anti-IgG autoantibodies could facilitate the development of canine immunotherapies and help in understanding and counteracting immunoassay interference. This study investigated the clinical significance and interconnection of heterophilic antibodies, anti-Fab, and anti-F(ab′)2-autoantibodies in dogs. We performed a 2-year prospective follow-up of dogs with heterophilic antibodies and analyzed serum for anti-Fab and anti-F(ab′)2-autoantibodies. Canine heterophilic antibodies can persist for at least 2 years in serum. A widespread occurrence of anti-Fab and anti-F(ab′)2-autoantibodies was found, with reactivity to cryptic epitopes in the IgG hinge region and sporadic cross-reactivity with mouse IgG. Canine anti-Fab and anti-F(ab′)2-autoantibodies are thus potential sources of clinical immunogenicity and immunoassay interference.
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| 2. |
- Helmersson-Karlqvist, Johanna, et al.
(författare)
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Association of Test Results for 33 Frequently Used Laboratory Tests with Body Mass Index (BMI)
- 2020
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Ingår i: CLINICAL AND EXPERIMENTAL INVESTIGATIONS. - Lewes. ; 1:1, s. 2-4
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Tidskriftsartikel (refereegranskat)abstract
- Once considered a problem only for high-income countries, obesity rates are now rising worldwide. When evaluating test results from obese patients it is important to be aware of the effect of obesity on individual laboratory test results. The aim of the present study was to study the association between body mass index (BMI) and a group of frequently requested laboratory tests to evaluate which of these analytes that are affected by BMI. We analyzed the association between body mass index (BMI) and Alanine aminotransaminase (ALT), Albumin, Alkaline phosphatase, Pancreatic amylase, Apolipoprotein A1, Apolipoprotein B, Apolipoprotein B/Apolipoprotein A1 ratio, Aspartate aminotransferase (AST), AST/ALT ratio, Bilirubin, Calcium, Calprotectin, Cholesterol, HDL-cholesterol, Creatinine kinase (CK), Creatinine, C-reactive protein, Cystatin C, Gamma-glutamyl transferase (GGT), Iron, Iron saturation, Lactate dehydrogenase (LDH), Magnesium, Phosphate, Transferrin, Triglycerides, Urate, Urea, Zink, Hemoglobin, Platelet count and White blood cell count in an 80-year old population (n=531, 266 females and 265 males). There were significant Spearman rank associations between BMI and laboratory test results for several of the studied markers in both females and males. The strongest associations with BMI were noted for ALT, Apolipoprotein A1, HDL-cholesterol, Hemoglobin, CRP, Cystatin C, Triglycerides and Urate. In conclusion, several of the most frequently used laboratory markers are significantly associated with BMI. To be able to correctly interpret a test result it is important to be aware of the effects of BMI on the test results.
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| 3. |
- Larsson, Anders, et al.
(författare)
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Evaluation of Automated Determination of Bilirubin and Oxyhemoglobin in Cerebrospinal Fluid Using the DrugLog© Instrument
- 2020
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Ingår i: Clinical Laboratory. - : Clinical Laboratory Publications. - 1433-6510. ; 66:11, s. 2357-2364
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: In a heterogenous group of patients with acute headache it is important to diagnose subarachnoid hemorrhage (SAH), a potentially lethal but treatable condition, with short turnaround time and high precision. Spectrophotometry of cerebrospinal fluid (CSF) is an essential part in the investigation of patients with suspected SAH but the analysis is slow and operator dependent.METHODS: We have evaluated a new instrument for ultraviolet and visible light (UV-VIS) spectroscopy (DrugLog©, Pharmacolog, Uppsala, Sweden) for automatic determination of oxyhemoglobin and bilirubin in CSF samples. The instrument incorporates software for calculating the absorbance values thus eliminating operator bias. Bilirubin and oxyhemoglobin in CSF was analyzed both with DrugLog© and traditional spectrophotometry at 415 and 476 nanometers (A415 and A476) using patient samples containing varying amounts of bilirubin and oxyhemoglobin.RESULTS: The DrugLog© method showed a strong correlation both for bilirubin (Pearson's r = 0.996) and oxyhemo-globin (Pearson's r = 0.993). The DrugLog© method had good linearity and precision, offering an automated determination of bilirubin and oxyhemoglobin, eliminating operator bias.CONCLUSIONS: The DrugLog© instrument has a short assay time and showed good agreement with traditional spectrophotometry.
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| 4. |
- Serapio, Solveig, et al.
(författare)
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Second Trimester Maternal Leptin Levels Are Associated with Body Mass Index and Gestational Weight Gain but not Birth Weight of the Infant
- 2020
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Ingår i: Hormone Research in Paediatrics. - : S. Karger. - 1663-2818 .- 1663-2826. ; 92:2, s. 106-114
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Obesity is increasing among the pregnant population. Leptin has an important role in the regulation of energy balance and hunger. The aim of this study was to investigate the association between maternal leptin levels with maternal obesity, gestational weight gain (GWG), single nucleotide polymorphisms (SNPs) within the leptin gene, and the age-adjusted birth weight of the child.MATERIAL AND METHODS: Maternal leptin levels (n = 740) and SNPs (n = 504) were analyzed in blood samples taken within the Uppsala Biobank of Pregnant women at pregnancy weeks 16-19.RESULTS: Maternal leptin levels differed significantly between body mass index (BMI) groups. Normal weight women had the lowest median leptin levels and levels increased with each BMI group. Leptin SNP genotype was not associated with leptin levels or BMI. There was also no association between maternal leptin levels and age-adjusted birth weight of the child except for a negative association between leptin levels and birth weight in the morbid obese group.DISCUSSION/CONCLUSION: Maternal BMI was identified as the best positive explanatory factor for maternal leptin levels. Leptin was a strong positive explanatory factor for GWG. Birth weight of children of uncomplicated pregnancies was, however, dependent on maternal height, BMI, GWG, and parity but not leptin levels, except for in morbid obese women where a negative association between maternal leptin levels and birth weight was found. We speculate that this indicates altered placental function, not manifested in pregnancy complication. We conclude that maternal leptin levels do not affect the birth weight of the child more than BMI, GWG, and parity.
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