A flow cytometry‐based assay to determine the phagocytic activity of both clinical and nonclinical antibody samples against Chlamydia trachomatis

Abstract

Globally, an estimated 131 million new cases of chlamydial infection occur annually. Chlamydia trachomatis infection can cause permanent damage to the fallopian tubes in woman, resulting in infertility and a risk of ectopic pregnancy. There is a great need for a vaccine against Chlamydia trachomatis and as a result there is a need for assays to evaluate functional immune responses for use in future clinical trials and epidemiological studies. Antibodies play a crucial role in the defense against infection and can be protective by several functions, including phagocytosis and neutralization. Vaccine development could greatly benefit from a method to measure functional C. trachomatis‐specific antibodies in a large number of samples. In the current in vitro antibody protection assays, which measure the capacity of antibodies to facilitate phagocytic uptake of C. trachomatis, the phagocytosed bacteria have to be counted manually. This is both labor demanding, time consuming, and it prevents high‐throughput usage of this method. In this study, we, therefore, developed a simple and rapid flow cytometry based assay to measure the capacity of antibodies to mediate Fc‐receptor dependent phagocytosis. This method is highly reproducible and suitable to analyze large numbers of clinical and nonclinical samples. © 2018 The Authors. Cytometry Part A Published by Wiley Periodicals, Inc. on behalf of ISAC.

A Chlamydia trachomatis VD1-MOMP vaccine elicits cross-neutralizing and protective antibodies against C/C-related complex serovars

“…is more than direct blocking of infection, i.e., by neutralization. A range of other indirect effector functions like opsonophagocytosis 54 , antibody-dependent complement deposition (ADCD) 55 , 56 , antibody-dependent cellular cytotoxicity (ADCC) 42 , or combinations thereof could potentially play a role. In this study, we demonstrated an in vivo protective effect of antibodies by preincubating C.t .…”

The Effects of Different Oil Sources on Performance, Digestive Enzymes, Carcass Traits, Biochemical, Immunological, Antioxidant, and Morphometric Responses of Broiler Chicks

“…The blood samples used for analyses were collected before the start of all vaccinations (day 0) and after the end of the last vaccination (day 29). Total antibody production specific for the NDV vaccine was determined in serum using commercial enzyme-linked immunosorbent assay (ELISA) kits (46). The antibody response was measured by the hemagglutination inhibition (HI) test (47).…”

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

“…The phagocytic index indicates the strength of the phagocytic cell, represented by the number of the ingested bacteria. Phagocytic activity is considered as the first line of defense against antigens and pathogenic agents (33,34). Total antibody production specific for NDV vaccine was determined in serum using commercial ELISA kits (35).…”