Assessment of disease specific immune responses in enteric diseases using dried blood spot (DBS)

• Published in: PloS one Vol. 14; no. 6; p. e0218353
• Main Authors: Bhuiyan, Md Saruar, Hossain, Motaher, Sharmin, Salma, Shirin, Afsana, Khanam, Farhana, Chowdhury, Fahima, Akter, Afroza, Khan, Ashraful Islam, Uddin, Muhammad Ikhtear, Bhuiyan, Taufiqur Rahman, Qadri, Firdausi
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17.06.2019; Public Library of Science (PLoS)
• Subjects: Analysis; Antibodies; Antibody Formation; Antibody response; Antigens; Biology and Life Sciences; Blood; Blood Specimen Collection - methods; Care and treatment; Cholera; Cholera - immunology; Cholera toxin; Cholera toxin B subunit; Cholera Vaccines - immunology; Clinical trials; Correlation analysis; Diagnosis; Diarrhea; Disease; Dried Blood Spot Testing - methods; Drug resistance; E coli; Enterotoxigenic Escherichia coli - immunology; Female; Fever; Health care; Heat; Hepatitis; Humanitarian aid; Humans; Immune response; Immunoglobulins; Infection; Infections; Infrastructure (Economics); Intestinal Diseases - immunology; Laboratories; Leprosy; Lipopolysaccharides; Male; Management; Manpower; Measurement methods; Medical research; Medicine and Health Sciences; Membrane proteins; Middle Aged; Mitogens; Outcome and process assessment (Medical care); Preservation; Research and Analysis Methods; Tropical diseases; Typhoid; Typhoid fever; Typhoid Fever - immunology; Vaccination; Vaccines; Waterborne diseases; Bangladesh; India
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0218353

Blood collection, transportation and storage remain a problem in countries where infrastructure, laboratory facilities and skilled manpower are scarce. This limits evaluation of immune responses in natural infections and vaccination in field studies. We developed methods to measure antigen specific antibody responses using dried blood spot (DBS) in cholera, ETEC and typhoid fever patients as well as recipients of oral cholera vaccine (OCV). We processed heparinized blood for preparing DBS and plasma specimens from patients with, cholera, ETEC and typhoid as well as OCV recipients. We optimized the conventional vibriocidal method to measure vibriocidal antibody response in DBS eluates. We measured responses in DBS samples and plasma (range of titer of 5 to 10240). Vibriocidal titer showed strong agreement between DBS eluates and plasma in cholera patients (ICC = 0.9) and in OCV recipients (ICC = 0.8) using the Bland-Altman analysis and a positive correlation was seen (r = 0.7, p = 0.02 and r = 0.6, p = 0.006, respectively). We observed a strong agreement of lipopolysaccharide (LPS) and cholera toxin B (CTB)-specific antibody responses between DBS eluates and plasma in cholera patients and OCV recipients. We also found agreement of heat labile toxin B (LTB) and membrane protein (MP)-specific antibody responses in DBS eluates and plasma specimen of ETEC and typhoid patients respectively. Our results demonstrate that dried blood specimens can be used as an alternate method for preservation of samples to measure antibody responses in enteric diseases and vaccine trials and can be applied to assessment of responses in humanitarian crisis and other adverse field settings.