scholarly journals Age dependent changes in circulating Tfh cells influence the development of functional antibodies to malaria in children.

2021 ◽  
Author(s):  
Jo-Anne Chan ◽  
Jessica Loughland ◽  
Lauren de la Parte ◽  
Satomi Okano ◽  
Isaac Ssewanyana ◽  
...  
Keyword(s):  
Cell Activation ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Malaria Exposure ◽  
Age Dependent ◽  
Functional Antibodies ◽  
Antibody Levels ◽  
Parasite Factors

T-follicular helper (Tfh) cells are key drivers of antibodies that protect from malaria. However, little is known regarding the host and parasite factors that influence Tfh and functional antibody development. Here, we use samples from a large cross-sectional study of children residing in an area of high malaria transmission in Uganda to characterize Tfh cells and functional antibodies to multiple parasites stages. We identify a dramatic re-distribution of the Tfh cell compartment with age that is independent of malaria exposure, with Th2-Tfh cells predominating in early childhood, while Th1-Tfh cell gradually increase to adult levels over the first decade of life. Functional antibody acquisition is age-dependent and hierarchical acquired based on parasite stage, with merozoite responses followed by sporozoite and gametocyte antibodies. Antibodies were boosted in children with current infection, and were higher in females. The children with the very highest antibody levels had increased Tfh cell activation and proliferation, consistent with a key role of Tfh cells in antibody development. Together, these data reveal a complex relationship between the circulating Tfh compartment, antibody development and protection from malaria.

scholarly journals Age dependent changes in circulating Tfh cells influence the development of functional antibodies to malaria in children.

2021 ◽  
Author(s):  
Jo-Anne Chan ◽  
Jessica Loughland ◽  
Lauren de la Parte ◽  
Satomi Okano ◽  
Isaac Ssewanyana ◽  
...  
Keyword(s):  
Cell Activation ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Tfh Cells ◽  
Follicular Helper ◽  
Malaria Exposure ◽  
Age Dependent ◽  
Functional Antibodies ◽  
Antibody Levels ◽  
Parasite Factors

Abstract T-follicular helper (Tfh) cells are key drivers of antibodies that protect from malaria. However, little is known regarding the host and parasite factors that influence Tfh and functional antibody development. Here, we use samples from a large cross-sectional study of children residing in an area of high malaria transmission in Uganda to characterize Tfh cells and functional antibodies to multiple parasites stages. We identify a dramatic re-distribution of the Tfh cell compartment with age that is independent of malaria exposure, with Th2-Tfh cells predominating in early childhood, while Th1-Tfh cell gradually increase to adult levels over the first decade of life. Functional antibody acquisition is age-dependent and hierarchical acquired based on parasite stage, with merozoite responses followed by sporozoite and gametocyte antibodies. Antibodies were boosted in children with current infection, and were higher in females. The children with the very highest antibody levels had increased Tfh cell activation and proliferation, consistent with a key role of Tfh cells in antibody development. Together, these data reveal a complex relationship between the circulating Tfh compartment, antibody development and protection from malaria.

scholarly journals Testosterone substitution of hypogonadal men prevents the age-dependent increases in body mass index, body fat and leptin seen in healthy ageing men: results of a cross-sectional study

2002 ◽  
pp. 505-511 ◽  
Author(s):  
C Rolf ◽  
S von Eckardstein ◽  
U Koken ◽  
E Nieschlag
Keyword(s):  
Fat Mass ◽  
Serum Testosterone ◽  
Cross Sectional Study ◽  
Fat Content ◽  
Sectional Study ◽  
Cross Sectional ◽  
Serum Leptin ◽  
Testosterone Substitution ◽  
Age Dependent ◽  
Total Fat

INTRODUCTION: In healthy men, body weight and total fat content increase with advancing age, while serum testosterone levels decrease. In order to elucidate whether a causal relationship between these phenomena exists, we investigated the influence of testosterone or human chorionic gonadotrophin substitution on body mass index (BMI), total fat mass and serum leptin in testosterone-treated and untreated hypogonadal patients in comparison with ageing eugonadal men. METHODS: In a cross-sectional study, the inter-relationships of body weight, total fat mass, serum sex hormones and leptin were analysed in untreated hypogonadal men (n=24; age 19-65 years), treated hypogonadal men (n=61; age 20-67 years) and healthy eugonadal men (n=60; age 24-78 years). Total fat mass was assessed by bioimpedance measurement. Univariate and multiple linear regression analysis was used to detect possible differences. RESULTS: In eugonadal men, serum testosterone levels decreased with advancing age (correlation coefficients: r=-0.71; P<0.0001), while BMI (r=0.39; P=0.002), total fat content (r=0.51; P<0.0001) and leptin (r=0.48; P<0.0001) increased significantly. In untreated hypogonadal patients, an increase in BMI (r=0.50; P=0.013) and total fat mass (r=0.41; P=0.044) was also observed with advancing age. However, in substituted hypogonadal patients, no age-dependent change in BMI (r=0.067; P=0.606), body fat content (r=-0.083; P=0.522), serum testosterone (r=-0,071; P=0.59) or serum leptin (r=-0.23; P=0.176) was found. CONCLUSION: Since testosterone-substituted older hypogonadal men show BMI and fat mass similar to those of younger eugonadal men and since non-treated hypogonadal men are similar to normal ageing men, testosterone appears to be an important factor contributing to these changes. Thus ageing men should benefit from testosterone substitution as far as body composition is concerned.

scholarly journals Production of SARS-CoV-2 Antibodies and Emergence of the Clinical Symptoms of COVID-19

2021 ◽  
Author(s):  
Ahmad Hormati ◽  
Hossein Poustchi ◽  
Mohammad Reza Ghadir ◽  
Saeede Jafari ◽  
Narges Jafari ◽  
...  
Keyword(s):  
Clinical Symptoms ◽  
Clinical Care ◽  
Public Health Problem ◽  
Cross Sectional Study ◽  
Clinical Findings ◽  
Time Duration ◽  
Cross Sectional ◽  
Igm Antibodies ◽  
Gi Symptoms ◽  
Antibody Levels

Coronavirus disease 2019 (COVID-19) is a worldwide public health problem that has attracted much attention due to its clinical findings. Measurement of IgG and IgM antibodies is of great importance for researchers and it will help to develop a new diagnostic and therapeutic method in clinical care. In this cross-sectional study, we aim to measure the IgG and IgM antibody levels in 401 suspected COVID-19 volunteers. We also measure the time duration for the appearance of IgG and IgM antibodies from the onset of symptoms to sampling time. Of 401 participants enrolled in the study, 255 (63.59%) were healthy, 79 (19.70%) were a carrier, 59 (14.71%) were cured and 8 (1.99%) were borderline. Of 142 subjects diagnosed with COVID-19, 41 (28.87%) presented with gastrointestinal (GI) symptoms, 83 (58.45%) had no GI symptoms, and 18 (12.68%) were asymptomatic. According to our findings, the measurement of IgG and IgM antibodies will provide the tool for the diagnosis of COVID-19 and significantly boost research into novel diagnostic and therapeutic approaches.

scholarly journals Telomere length and age-dependent telomere attrition: the blood-and-muscle model

2019 ◽  
Vol 97 (4) ◽  
pp. 328-334 ◽  
Author(s):  
Mirna N. Chahine ◽  
Simon Toupance ◽  
Sandy El-Hakim ◽  
Carlos Labat ◽  
Sylvie Gautier ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Telomere Length ◽  
Cross Sectional Study ◽  
Muscle Model ◽  
Atherosclerotic Cardiovascular Disease ◽  
Cross Sectional ◽  
Telomere Attrition ◽  
Age Related ◽  
Age Dependent ◽  
Muscle Biopsies

Short telomere length (TL) is associated with atherosclerotic cardiovascular disease (ACVD) and other age-related diseases. It is unclear whether these associations originate from having inherently short TL or a faster TL attrition before or during disease development. We proposed the blood-and-muscle model to assess TL dynamics throughout life course. Our objective was to measure TL in leukocytes (LTL) and in skeletal muscle (MTL), which served as a proxy of TL at birth. The delta (MTL–LTL) represented life-long telomere attrition. Blood draws and skeletal muscle biopsies were performed on 35 Lebanese individuals undergoing surgery. Following DNA extraction, LTL and MTL were measured by Southern blot. In every individual aged between 30 and 85 years, MTL was longer than LTL. With age, MTL and LTL decreased, but the delta (MTL–LTL) increased by 14 bp/year. We validated the blood-and-muscle model that allowed us to identify TL, TL at birth, and lifelong TL attrition in a cross-sectional study. This model can be used in larger cross-sectional studies to evaluate the association of telomere dynamics with age-related diseases onset and progression.

scholarly journals LegionellaAntibodies in a Danish Hospital Staff with Known Occupational Exposure

2009 ◽  
Vol 2009 ◽  
pp. 1-6 ◽  
Author(s):  
M. Rudbeck ◽  
S. Viskum ◽  
K. Mølbak ◽  
S. A. Uldum
Keyword(s):  
Health Care ◽  
Blood Donors ◽  
Reference Group ◽  
Hospital Staff ◽  
Cross Sectional Study ◽  
Hospital Workers ◽  
Cross Sectional ◽  
Staff Members ◽  
Antibody Titres ◽  
Antibody Levels

Although legionnaires' disease frequently is acquired in health care institutions, little is known about the occupational risk ofLegionellainfection among health care workers. The aim of the present cross-sectional study was to analyse antibody levels among exposed hospital workers and to determine the correlation between antibodies toLegionellaand self-reported symptoms. The study included 258 hospital employees and a reference group of 708 healthy blood donors. Hospital workers had a higher prevalence ofLegionellaantibody titres (1 : 128) than blood donors (odds ratio 3.4; 95% CI 2.4–4.8). Antibody levels were not higher among staff members at risk of frequent aerosol exposure than among less exposed employees. There was no consistent association between a history of influenza-like symptom complex and the presence of antibodies. The results indicate that hospital workers have a higher risk ofLegionellainfections than the general population. However, since no excess morbidity was associated with seropositivity, mostLegionellainfections may be asymptomatic.

Antibody Profile of Colostrum and the Effect of Processing in Human Milk Banks: Implications in Immunoregulatory Properties

2017 ◽  
Vol 34 (1) ◽  
pp. 137-147 ◽  
Author(s):  
Claudio Rodríguez-Camejo ◽  
Arturo Puyol ◽  
Laura Fazio ◽  
Analía Rodríguez ◽  
Emilia Villamil ◽  
...  
Keyword(s):  
Cross Sectional Study ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cross Sectional ◽  
Convenience Sample ◽  
Specific Antibodies ◽  
Specific Reactivity ◽  
Antibody Profile ◽  
Milk Banks ◽  
Antibody Levels ◽  
Mother’S Own Milk

Background: When feeding preterm infants, donor milk is preferred if the mother’s own milk is unavailable. Pasteurization may have detrimental effects on bioactivity, but more information is needed about its effects on the immunological compounds. Research aim: This work has two main aims: evaluate the antibody profile of colostrum and study the quantitative variations in the antibodies’ level and specific reactivity after undergoing Holder pasteurization. The authors focused on immunoregulatory components of colostrum (antidietary antibodies and TGF-β2) in the neonatal gut. Methods: This is a descriptive cross-sectional study of a convenience sample of 67 donated colostrum samples at different days after delivery, both raw and pasteurized. Antibody profiles were analyzed at different times during breastfeeding, and total and specific antibodies (IgM, IgA, and IgG subclasses) were compared with tetanus toxoid and ovalbumin using enzyme-linked immunosorbent assay. The processing effect on total and specific antibodies, as well as TGF-β2, was evaluated by paired analyses. Results: No variations in immunological compounds were observed throughout the colostrum stage. The TGF-β2, antibodies’ concentrations, and antibodies’ specific reactivity after pasteurization did not vary significantly as days of lactation varied. Changes in antibody levels were dependent on isotype and IgG subclass, and IgG4 showed remarkable resistance to heating. Moreover, the effect of the pasteurization on specific reactivity was antigen dependent. Conclusion: The supply of relevant immunological components is stable throughout the colostrum stage. The effects of pasteurization on antibodies depend on isotype, subclass, and specificity. This information is relevant to improving the immunological quality of colostrum, especially for preterm newborns.

scholarly journals Estimating SARS-CoV-2 Spike Antibody Levels Among Sputnik V First Dose Vaccinated People in Pakistan: Formulation of Anti-COVID-19 National Mass Vaccination Strategy.

2021 ◽  
Author(s):  
Umar Saeed ◽  
Sara Rizwan Uppal ◽  
Zahra Zahid Piracha ◽  
Aftab Ahmad Khan ◽  
Azhar Rasheed ◽  
...  
Keyword(s):  
Antibody Titer ◽  
Previous History ◽  
Vaccination Strategy ◽  
Cross Sectional Study ◽  
Mass Vaccination ◽  
Spike Protein ◽  
Cross Sectional ◽  
Diagnostic Center ◽  
Antibody Titers ◽  
Antibody Levels

Abstract Rapid ramp up of immune responses against SARS-CoV-2 during pandemic enables adequate prevention and treatment for COVID-19. Estimating levels of SARS-CoV-2 spike protein antibodies post vaccination is crucial for designing mass-vaccination strategies. The aim of this study was to evaluate effectiveness of Sputnik V first dose in Pakistan. A cross-sectional study of 2000 participants was conducted for examining Gam-COVID-Vac or Sputnik V first dose effects at 21st days post administration at Islamabad Diagnostic Center, Islamabad, Pakistan. From 100 real-time PCR negative (SARS-CoV-2 RNA) individuals, samples were collected and analyzed for antibodies to the SARS-CoV-2 spike protein using Electro-chemiluminescence immunoassay (ECLIA) (Elecsys # 09289267190 Roche, USA). 85% of the participants showed strong positive results with SARS-CoV-2 spike protein antibodies >1.5 AU/ml. The individuals with antibody titer >250 AU/ml were 34.9%. Among those with antibody levels >250 AU/ml 52% had previous history of COVID-19 infection. While participants with >100 AU/ml of antibodies were 12.7%. However 9.5% showed antibody titer of >25 AU/ml. 27% of participants had antibody titers of >1.5-2.5 AU/ml. While antibody titers of <1.5 AU/ml were observed among 15.9% of participants. Majority of the individuals represented significantly high antibody titers against SARS-CoV-2 even before second booster dose of Ad5 based Sputnik V vaccine. Continuous monitoring of antibody levels among COVID-19 vaccinated populations are deemed to assess humoral immunity status against SARS-CoV-2 infections.

scholarly journals IgM Anti PGL-1 Antibody Level in Patients with Leprosy: A Comparative Study between Ear Lobes Capillary and Median Cubital Vein Blood Samples

2018 ◽  
Vol 6 (8) ◽  
pp. 1346-1348
Author(s):  
Khairina Nasution ◽  
Kristina Nadeak ◽  
Syahril Rahmat Lubis
Keyword(s):  
Blood Sample ◽  
Filter Paper ◽  
Cross Sectional Study ◽  
Mean Value ◽  
Cross Sectional ◽  
Blood Samples ◽  
Significant Difference ◽  
Median Cubital Vein ◽  
The Mean ◽  
Antibody Levels

BACKGROUND: To establish the diagnosis of leprosy accurately, additional examination such as serologic examination with ELISA is required. There are considerations about taking a blood sample from the earlobe region.AIM: To determine the differences in IgM anti-PGL-1 antibody levels from earlobe capillary and median cubital vein blood sample in leprosy patients.METHODS: An observational analytic study using a cross-sectional study involving 30 patients with leprosy. ELISA examination of earlobe blood samples with filter paper, and the median cubital vein blood samples with filter paper and conventional methods were performed to determine IgM anti-PGL-1 antibody levels.RESULTS: The mean value of IgM anti PGL-1 antibody levels from earlobe blood samples with filter paper (1476.62 μ/ml) was relatively similar with median cubital vein blood samples with conventional method (1476.77 μ/ml), but the mean value of IgM anti PGL-1 antibody levels from median cubital vein blood samples with filter paper (1210.37 μ/ml) was lower from other methods. However, there was no statistically significant difference between them.CONCLUSION: There are no significant differences between the mean levels of IgM anti-PGL-1 antibody from earlobe and the median cubital vein blood samples.

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