Plasma Donors in the Southwestern United States Positively Contribute to the Diverse Therapeutic Antibody Profile of Immune Globulin Products.

Human-plasma-derived immune globulin (IG) is used in augmentation therapy to provide protective levels of antibodies to patients with primary immune deficiency diseases (PIDD) and for prophylaxis against infectious diseases. To maintain the breadth of antibodies necessary for clinical protection, it is important to understand regional patterns of antibody seroprevalence in source plasma from which IG products are manufactured. In this study, source plasma from donation centers in various locations of the Southwestern quarter of the United States was surveyed for antibody titers to hepatitis A virus (HAV), measles virus (MeV), and cytomegalovirus (CMV). A broad range of anti-HAV Ig plasma titers was observed among these centers, with some centers exhibiting 3-5 times the titers of the others. Minor to no differences were observed for levels of anti-MeV and anti-CMV, respectively. Importantly, elevated anti-HAV Ig titers were broadly observed across plasma units obtained from the centers exhibiting high titers, indicative of a potential regional phenomenon among donors as opposed to few donors with singularly high titers. Plasma from these high-titer centers conferred significantly greater neutralization against HAV in vitro. The outcomes of this study give a glimpse of the antibody diversity inherent in human plasma used to manufacture IG products..

Discovery and analysis of a novel parvovirus B19 Genotype 3 isolate in the United States.

BACKGROUND: Parvovirus B19 (B19V) is a pathogen frequently identified in human plasma donations through the detection of nucleic acids. Three B19V genotypes have been defined based on isolates having greater than 10% divergence in overall DNA sequence. B19V Genotype 3 is a rarely occurring genotype that has been detected primarily in Ghana with sporadic reports in Brazil and France but has not been previously reported in North America. STUDY DESIGN AND METHODS: A polymerase chain reaction assay was developed with broad specificity for B19V detection. The performance of this assay was assessed by testing approximately 440,000 clinical samples representing more than 81,000 individual donors. Determinations of B19V titer, DNA sequence, and antibody concentrations were performed on samples of interest. RESULTS: This assessment identified a series of eight plasma donations spanning 28 days from a single donor in the United States infected with B19V Genotype 3 as confirmed by DNA sequence analysis. The B19V titer of this series of donations showed virus titers that peaked at greater than 10(11) IU/mL. The virus titer decreased significantly over the next several donations coinciding with an increase in immunoglobulin M (IgM) levels. The immunoglobulin G levels also increased but lagged approximately 7 days behind the IgM levels. CONCLUSION: This is the first report of a B19V Genotype 3 detected from a plasma donor located in the United States. Although our data are consistent with recent reports suggesting low incidence for this genotype, they indicate its increasing relevance among blood and plasma donors.

Ensuring the biologic safety of plasma-derived therapeutic proteins: detection, inactivation, and removal of pathogens.

Human plasma-derived proteins, such as immunoglobulins, coagulation factors, alpha1-antitrypsin, fibrin sealants, and albumin, are widely used as therapeutics for many serious and life-threatening medical conditions. The human origin of these proteins ensures excellent efficacy and compatibility but may also introduce the risk of unintentional disease transmission. Historically, only viruses, particularly hepatitis and HIV, have posed serious threats to the safety of these therapeutics. Fortunately, between 1970 and 1990, the molecular biology of each of the major viruses was elucidated. These advances led to the development and implementation of effective donor screening tests, mainly based on immunoassays and nucleic acid testing, which resulted in a significant reduction of disease transmission risk. In addition, viral inactivation and removal steps were implemented and validated by manufacturers, further reducing the risk associated with known, as well as unidentified, viruses. Since the late 1990s, a different class of transmissible agent, referred to as prions, has been identified as a new risk for disease transmission. However, prion diseases are very rare, and prion transmission through plasma-derived proteins has not been reported to date. The prion-related risk is minimized by deferring donors with certain key risk factors, and by the manufacturing processes that are capable of removing prions. Advances in science and pathogen safety-related technology, compliance with good manufacturing practices by manufacturers, and increasingly stringent regulatory oversight, has meant that plasma-derived proteins have been developed into today's highly effective therapeutics with very low risk of disease transmission.