Simple assay systems for infectivity titrations of avian infectious bronchitis virus (IBV) in chicken embryo trachea organ cultures (OC) were developed using plastic multiplate wells with one tracheal ring per well; these assays appeared to be much more satisfactory than the conventional rolled-tube method. The medium, 0.05 M HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid)-buffered ...

Nipah virus (NiV) and Hendra virus (HeV) are zoonotic paramyxoviruses capable of causing severe disease in humans and animals. These viruses require biosafety level 4 (BSL-4) containment. Like other paramyxoviruses, the plaque reduction neutralization test (PRNT) can be used to detect antibodies to the surface glycoproteins, fusion (F) and attachment (G), and PRNT titers give an indication of p...

Ebola virus is currently causing an unprecedented outbreak in West Af-rica. The pathogen is classified as a biosafety level 4 (BSL-4) 1 pathogen and should be handled only in high-level biosafety settings (1). Virus neutralization is considered to be the gold standard serological assay for infections, but in the case of Ebola, this test requires culturing of live virus in a BSL-4 facility. Beca...

The available virus-like particle (VLP)-based prophylactic vaccines against specific human papillomavirus (HPV) types afford close to 100% protection against the type-associated lesions and disease. Based on papillomavirus animal models, it is likely that protection against genital lesions in humans is mediated by HPV type-restricted neutralizing antibodies that transudate or exudate at the sit...

BACKGROUND Cross-immunity between seasonal and pandemic A/H1N1 influenza viruses remains uncertain. In particular, the extent that previous infection or vaccination by seasonal A/H1N1 viruses can elicit protective immunity against pandemic A/H1N1 is unclear. METHODOLOGY/PRINCIPAL FINDINGS Neutralizing titers against seasonal A/H1N1 (A/Brisbane/59/2007) and against pandemic A/H1N1 (A/Californi...

Porcine transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PDEV) can cause severe diarrhea in pigs. Development of effective vaccines against TGEV and PEDV is one of important prevention measures. The spike (S) protein is the surface glycoprotein of TGEV and PEDV, which can induce specific neutralization antibodies and is a candidate antigen for vaccination attempts...

In the USA, the potency of commercially prepared equine tetanus antitoxin is determined by the method outlined in the Code of Federal Regulations, Title 9, Part 113.451. In the current test, commercial equine tetanus antitoxin is tested by a toxin neutralization test in guinea pigs. The in vivo test measures antitoxin content through effectiveness of protection of guinea pigs injected with dilu...

Antigenic variation among 13 Quebec isolates of bovine viral diarrhea virus (BVDV), 4 reference strains and 2 American isolates were studied by peroxidase-linked antibody assay (PLA assay) and neutralization test (NT). The Quebec strains consisted of 3 isolates before 1993 and 10 isolates from 1993. In the PLA assay, we compared 2 different fixatives, acetone and formalin. Acetone-fixation allo...

BACKGROUND: Infectious Bovine Rhinotrachitis (IBR) caus-ed by Bovine Herpes Virus-1 (BoHV-1) was first, observed in one of the Tehran Industrial cattle breeders, with importation of cattle in 1965. Later, the isolation of bovine herpes virus approved the existence of the disease in the most of the provinces of the Iran. OBJECTIVES: Presence of antibodies against BoHV-1 was evaluated in young bo...

background: induced abortion is not only a serious threat for women’s health, but also a controversial topic for its ethical and moral problems. we aimed to evaluate the relationship between neutralization techniques and attempting to commit abortion in married women with unintended pregnancy. methods: after in-depth interviews with some women who had attempted abortion, neutralization themes w...