Increased Serum Antibody Titers Research Articles

The effect of metformin on influenza vaccine responses in nondiabetic older adults: a pilot trial

BackgroundAging is associated with progressive declines in immune responses leading to increased risk of severe infection and diminished vaccination responses. Influenza (flu) is a leading killer of older adults despite availability of seasonal vaccines. Geroscience-guided interventions targeting biological aging could offer transformational approaches to reverse broad declines in immune responses with aging. Here, we evaluated effects of metformin, an FDA approved diabetes drug and candidate anti-aging drug, on flu vaccination responses and markers of immunological resilience in a pilot and feasibility double-blinded placebo-controlled study.ResultsHealthy older adults (non-diabetic/non-prediabetic, age: 74.4 ± 1.7 years) were randomized to metformin (n = 8, 1500 mg extended release/daily) or placebo (n = 7) treatment for 20 weeks and were vaccinated with high-dose flu vaccine after 10 weeks of treatment. Peripheral blood mononuclear cells (PBMCs), serum, and plasma were collected prior to treatment, immediately prior to vaccination, and 1, 5, and 10 weeks post vaccination. Increased serum antibody titers were observed post vaccination with no significant differences between groups. Metformin treatment led to trending increases in circulating T follicular helper cells post-vaccination. Furthermore, 20 weeks of metformin treatment reduced expression of exhaustion marker CD57 in circulating CD4 T cells.ConclusionsPre-vaccination metformin treatment improved some components of flu vaccine responses and reduced some markers of T cell exhaustion without serious adverse events in nondiabetic older adults. Thus, our findings highlight the potential utility of metformin to improve flu vaccine responses and reduce age-related immune exhaustion in older adults, providing improved immunological resilience in nondiabetic older adults.

Mathematical modelling of the waning of anti-RBD IgG SARS-CoV-2 antibody titers after a two-dose BNT162b2 mRNA vaccination.

After exposure to SARS-CoV-2 and/or vaccination there is an increase in serum antibody titers followed by a non-linear waning. Our aim was to find out if this waning of antibody titers would fit to a mathematical model. We analyzed anti-RBD (receptor binding domain) IgG antibody titers and the breakthrough infections over a ten-month period following the second dose of the mRNA BNT162b2 (Pfizer-BioNtech.) vaccine, in a cohort of 54 health-care workers (HCWs) who were either never infected with SARS-CoV-2 (naïve, nHCW group, n=27) or previously infected with the virus (experienced, eHCW group, n=27). Two mathematical models, exponential and power law, were used to quantify antibody waning kinetics, and we compared the relative quality of the goodness of fit to the data between both models was compared using the Akaik Information Criterion. We found that the waning slopes were significantly more pronounced for the naïve when compared to the experienced HCWs in exponential (p-value: 1.801E-9) and power law (p-value: 9.399E-13) models. The waning of anti-RBD IgG antibody levels fitted significantly to both exponential (average-R2: 0.957 for nHCW and 0.954 for eHCW) and power law (average-R2: 0.991 for nHCW and 0.988 for eHCW) models, with a better fit to the power law model. In the nHCW group, titers would descend below an arbitrary 1000-units threshold at a median of 210.6 days (IQ range: 74.2). For the eHCW group, the same risk threshold would be reached at 440.0 days (IQ range: 135.2) post-vaccination. Two parsimonious models can explain the anti-RBD IgG antibody titer waning after vaccination. Regardless of the model used, eHCWs have lower waning slopes and longer persistence of antibody titers than nHCWs. Consequently, personalized vaccination booster schedules should be implemented according to the individual persistence of antibody levels.

Infectivity and transmissibility of an avian H3N1 influenza virus in pigs

In 2019 a low pathogenic H3N1 avian influenza virus (AIV) caused an outbreak in Belgian poultry farms, characterized by an unusually high mortality in chickens. Influenza A viruses of the H1 and H3 subtype can infect pigs and become established in swine populations. Therefore, the H3N1 epizootic raised concern about AIV transmission to pigs and from pigs to humans. Here, we assessed the replication efficiency of this virus in explants of the porcine respiratory tract and in pigs, using virus titration and/or RT-qPCR. We also examined transmission from directly, intranasally inoculated pigs to contact pigs. The H3N1 AIV replicated to moderate titers in explants of the bronchioles and lungs, but not in the nasal mucosa or trachea. In the pig infection study, infectious virus was only detected in a few lung samples collected between 1 and 3 days post-inoculation. Virus titers were between 1.7 and 4.8 log10 TCID50. In line with the ex vivo experiment, no virus was isolated from the upper respiratory tract of pigs. In the transmission experiment, we could not detect virus transmission from directly inoculated to contact pigs. An increase in serum antibody titers was observed only in the inoculated pigs. We conclude that the porcine respiratory tract tissue explants can be a useful tool to assess the replication efficiency of AIVs in pigs. The H3N1 AIV examined here is unlikely to pose a risk to swine populations. However, continuous risk assessment studies of emerging AIVs in pigs are necessary, since different virus strains will have different genotypic and phenotypic traits.

Recombinant suilysin of Streptococcus suis enhances the protective efficacy of an engineered Pasteurella multocida toxin protein

Suilysin (Sly) from Streptococcus suis has been shown to elicit strong immune responses and may act as a vaccine adjuvant. In the present study, we tested the adjuvant effect of Sly using an engineered Pasteurella multocida toxin, rPMT-NC, as the antigen. The antigen was also formulated with other conventional adjuvants (aluminum hydroxide, water-in-oil-in-water) for comparison. The efficacy of these vaccine formulations were evaluated in mice. The optimal dosage of purified rSly for enhancing immune responses in mice was first determined to be 40 μg/ml based on significantly (p < 0.05) increased serum antibody titers, expression of cytokines, including interleukin (IL)-4, IL-12, and interferon (IFN)-γ and the survival rate after challenge with P. multocida. Mice immunized with rPMT-NC + rSly had augmented antibody production and cellular immunity compare to those immunized with rPMT-NC plus other adjuvants. In addition, the survival rate of mice immunized with rPMT-NC + rSly was the highest (70% v.s. 30% of mice immunized with rPMT-NC alone) among all groups. In conclusion, rSly has the potential to be used as a biological adjuvant to enhance immune responses and protective efficacy of protein-based vaccines.

Hemagglutinin Functionalized Liposomal Vaccines Enhance Germinal Center and Follicular Helper T Cell Immunity.

Despite remarkable successes of immunization in protecting public health, safe and effective vaccines against a number of life‐threatening pathogens such as HIV, ebola, influenza, and SARS‐CoV‐2 remain urgently needed. Subunit vaccines can avoid potential toxicity associated with traditional whole virion‐inactivated and live‐attenuated vaccines; however, the immunogenicity of subunit vaccines is often poor. A facile method is here reported to produce lipid nanoparticle subunit vaccines that exhibit high immunogenicity and elicit protection against influenza virus. Influenza hemagglutinin (HA) immunogens are functionalized on the surface of liposomes via stable metal chelation chemistry, using a scalable advanced microfluidic mixing technology (NanoAssemblr). Immunization of mice with HA‐liposomes elicits increased serum antibody titers and superior protection against highly pathogenic virus challenge compared with free HA protein. HA‐liposomal vaccines display enhanced antigen deposition into germinal centers within the draining lymph nodes, driving increased HA‐specific B cell, and follicular helper T cell responses. This work provides mechanistic insights into highly protective HA‐liposome vaccines and informs the rational design and rapid production of next generation nanoparticle subunit vaccines.

Innate Immune Molecule NLRC5 Protects Mice From Helicobacter-induced Formation of Gastric Lymphoid Tissue

Helicobacter pylori induces strong inflammatory responses that are directed at clearing the infection, but if not controlled, these responses can be harmful to the host. We investigated the immune-regulatory effects of the innate immune molecule, nucleotide-binding oligomerization domain-like receptors (NLR) family CARD domain-containing 5 (NLRC5), in patients and mice with Helicobacter infection. We obtained gastric biopsies from 30 patients in Australia. We performed studies with mice that lack NLRC5 in the myeloid linage (Nlrc5møKO) and mice without Nlrc5 gene disruption (controls). Some mice were gavaged with H pylori SS1 or Helicobacter felis; 3 months later, stomachs, spleens, and sera were collected, along with macrophages derived from bone marrow. Human and mouse gastric tissues and mouse macrophages were analyzed by histology, immunohistochemistry, immunoblots, and quantitative polymerase chain reaction. THP-1 cells (human macrophages, controls) and NLRC5-/- THP-1 cells (generated by CRISPR-Cas9 gene editing) were incubated with Helicobacter and gene expression and production of cytokines were analyzed. Levels of NLRC5 messenger RNA were significantly increased in gastric tissues from patients with H pylori infection, compared with patients without infection (P < .01), and correlated with gastritis severity (P < .05). H pylori bacteria induced significantly higher levels of chemokine and cytokine production by NLRC5-/- THP-1 macrophages than by control THP-1 cells (P < .05). After 3 months of infection with H felis, Nlrc5mø-KO mice developed gastric hyperplasia (P < .0001), splenomegaly (P < .0001), and increased serum antibody titers (P < .01), whereas control mice did not. Nlrc5mø-KO mice with chronic H felis infection had increased numbers of gastric B-cell follicles expressing CD19 (P < .0001); these follicles had features of mucosa-associated lymphoid tissue lymphoma. We identified B-cell-activating factor as a protein that promoted B-cell hyperproliferation in Nlrc5mø-KO mice. NLRC5 is a negative regulator of gastric inflammation and mucosal lymphoid formation in response to Helicobacter infection. Aberrant NLRC5 signaling in macrophages can promote B-cell lymphomagenesis during chronic Helicobacter infection.

Adaptogenic and immunomodulatory activity of Virgozest Avaleha - An ayurvedic proprietary formulation.

Introduction:Rasayana (rejuvenator) or adaptogenic drugs have been proved to produce the complete potential to prevent diseases and degenerative changes that leads to diseases and promote longevity by providing strength and immunity. Virgozest Avaleha is a poly-herbal formulation claimed to serve as adaptogenic, and immunomodulatory, as a health tonic, enriched with dry fruits, and ingredients containing natural supplements of Vitamin E and proteins.Aim:To evaluate the adaptogenic activity and humoral immune activity of virgozest Avaleha in Wistar albino rats.Materials and methods:Virgozest Avaleha was evaluated for adaptogenic activity against swimming stress-induced changes and hypothermia in albino rats. The humoral immune activity of virgozest Avaleha was evaluated against sheep red blood cells (SRBCs)-induced response in albino rats with the inclusion of cyclophosphamide as immune suppressant agent.Results:In adaptogenic activity, virgozest Avaleha (450 and 900 mg/kg) exhibited an increase in physical activity, decrease in stress-induced hypothermia, and serum cortisol level when compared to the stress control group of albino rats. In humoral immune activity, virgozest Avaleha reversed the effects of cyclophosphamide-induced adverse changes on spleen and lymph node, and produced a significant increase in serum antibody titer in SRBCs-sensitized rats.Conclusion:The present study concluded that virgozest Avaleha has adaptogenic and humoral immune activity in Wistar albino rats, which may suggest the Rasayana like properties of Ayurvedic formulation.

A recombinant vaccine of Riemerella anatipestifer OmpA fused with duck IgY Fc and Schisandra chinensis polysaccharide adjuvant enhance protective immune response

Riemerella anatipestifer (R. anatipestifer) causes septicemia and infectious serositis in domestic ducks, leading to high mortality and great economic losses worldwide. Vaccination is currently considered the best strategy to prevent R. anatipestifer infection in ducklings. In this study, we fused the duck IgY Fc gene to the outer membrane protein A (ompA) of R. anatipestifer. The eukaryotic expression plasmid carrying the fusion gene was transformed into Pichia pastoris (P. pastoris) to express the recombinant ompA and ompA–Fc proteins. Then, the effects of fused Fc on the vitality and antigen processing efficiency of duck peritoneal macrophages (PMø) were evaluated in vitro, whereas their immunogenicity was evaluated in vivo. Furthermore, Schisandra chinensis polysaccharide (SCP) was used to evaluate its immune-conditioning effects on the activation of PMø. SCP was also used as adjuvant to investigate immunomodulation on immunoresponses induced by the fused ompA-Fc in ducklings. The conventional Freund's incomplete adjuvant served as the control of SCP. Notably, ompA-Fc promoted phagocytosis of PMø and significantly increased serum antibody titers, CD4+ and CD8+ T-lymphocyte counts, lymphocyte transformation rate, and serum levels of IL-2 and IL-4. In addition, ducklings injected with the ompA-Fc vaccine exhibited considerably greater resistance to the R. anatipestifer challenge than those that received vaccines based on standalone ompA. Of note, SCP was demonstrated to boost the secretion of nitric oxide (NO), IL-1β, IL-6, TNF-α, and IFN-β by duck macrophages. In addition, the supplementation of SCP adjuvant to the ompA-Fc vaccines led to the further enhancement of immune response and vaccine protection. The dose of 200 μg/mL showed the most pronounced effects. This study provided valuable insights into protective strategies against R. anatipestifer infection.

A review of global human infection with avian influenza and epidemiological characteristics

Avian influenza virus is an influenza A virus, which generally spreads among birds, without direct infection of human. According to the pathogenicity to chicken or turkey, it is divided into high, medium and low/non pathogenic. When the virus gene recombination or mutation, it will get the ability to infect human. Additionally, avian influenza virus can also infect human directly, such as H5N1, H7N9, H5N6, H10N8 subtype. The cases of human infection with avian influenza reported frequently after the outbreak of human infection with H7N7 avian influenza in 1959, the first death case due to avian influenza virus infection causing respiratory disease was the outbreak of human infection with H5N1 in Hongkong in 1997. To date, human infection with avian influenza is a global public health problem. As avian influenza viruses perpetuated in their natural hosts, with their high genetic divergence, it would be precursor viruses even for pandemic potential. In the 20th century, four influenza pandemics were closely related to avian influenza viruses, avian is the natural host of the avian influenza virus, poultry carrying virus and dead/sick poultry infected with avian influenza virus are easier to spread virus to human, the main transmission routes are birds-human transmission (exposure to sick/dead poultry) and environment-human transmission (such as visit live poultry market). Poultries exposure and chronic medical condition are the main risk factors of human infection with avian influenza. The symptoms varies including ordinary influenza-like illness (ILI), conjunctivitis, arthritis, severe pneumonia, respiratory failure , shock and death. At present, the treatment of human infection with avian influenza includes antiviral treatment, symptomatic treatment, Chinese medicine treatment, but the most important therapy of human infection with avian influenza is the treatment of antiviral drugs (neuraminidase inhibitors), using high dose antiviral drugs in the early stage can significantly improve the survival rate. PCR and real-time PCR are the best methods for preliminary diagnosis of human infection with avian influenza. At the same time, the increase of serum antibody titer in acute stage or recovery stage can alao be confirmed. In addition, effective preventive measures (such as publicity and education, behavioral intervention and vaccination development and application) are the important means to protect human from avian influenza.

Achyranthes aspera extract against Pseudomonas fluorescens enhance antibody production in Labeo rohita

Indian major carp, rohu, (Labeo rohita) (30±6g), were fed with two types of diets; an experimental diet, containing root extract (0.5%) of Achyranthes aspera as an ingredient and control diet without the root extract. Experimental rohu were injected intraperitoneally with Pseudomonas fluorescens (3.2×10-6 CFU ml-1) and bloods were sampled 14 and 28 days post immunization. Though hemagglutination antibody (HA) titers were always higher in the test group than the control group, antigen-specific antibody and total serum globulin levels peaked on day 14 after immunization and steadily reduced towards day 28. Beside this, the results showed that dietary supplementation of A. aspera in test group showed significantly increased serum antibody titer (3280) and growth factors (41.1%) of L. rohita (P

Immune response of gilts to single and double infection with porcine epidemic diarrhea virus.

Immune response of gilts following single and double infection with porcine epidemic diarrhea virus (PEDV) at gilt acclimatization and prepartum were investigated. One hundred PEDV-naïve gilts were divided into two groups: negative (Neg) and feedback (FB) groups. Antibody responses in serum, colostrum, and milk samples were measured by IgG/IgA ELISA and virus neutralization assay (VN). Fecal shedding was investigated using RT-PCR. In summary, a single infection at gilt acclimatization resulted in slightly increased serum antibody titers as determined by VN assay and IgG ELISA, but not by IgA ELISA. Viral RNA was detected in fecal samples up to 6days post-exposure. A double infection at prepartum resulted in significantly increased IgA and VN titers in milk samples compared to the single-infection group. No fecal shedding was detected following the double infection.

Increased Serum Antibody Titer against HPV-16 Antigen in Patients with Behçet's Disease.

Quadrivalent human papillomavirus (HPV) vaccine has been reported to be significantly associated with Behçet's disease (BD). However, no reports have described HPV infection as a possible cause for the development of BD. The objective of this study was to evaluate whether anti-HPV immunoglobulin G (IgG) antibody titer is increased in BD. Serum samples from 93 Korean BD patients, who fulfilled the diagnostic criteria of the International Study Group for BD, were used in an enzyme-linked immunosorbent assay (ELISA). The clinical activity of BD was evaluated at the time of blood sampling. HPV-16 L1 virus-like particle (VLP) antigen was used in this study for the ELISA. Patients with BD had significantly higher antibody titers against HPV-16 (optical density [OD], 0.210–3.675; mean 0.992) than that of healthy controls (OD, 0.248–0.762; mean 0.517; P < 0.001). Using a receiver operating characteristic (ROC) analysis, a cut-off value of 0.578 OD for the anti-HPV antibody titer was determined that differentiated BD patients from healthy controls. When we compared the clinical features of BD between the 2 groups, articular involvement of BD was more likely in patients with an anti-HPV-16 antibody titer < 0.578 OD (P = 0.035). In addition, patients with an anti-HPV-16 antibody titer < 0.578 were significantly younger than those with a titer ≥ 0.578 OD. HPV itself may be a possible extrinsic triggering infectious agent causing the development of BD.

Achyranthes aspera Extract as feed additives enhances immunological parameters and growth performance in Pangasius pangasius against Pseudomonas fluorescens

Pangus (Pangasius pangasius) has been increasing for its high potential and play vital role in aquaculture in Bangladesh. The effects of dietary A. aspera supplementation on innate immunity, growth and disease against P. fluorescens infection were evaluated in Pangus (P. pangasius). Fish were feeding for 28 days with control diet and three experimental diets containing A. aspera herbal diet which were prepared with at 0%, 0.5%, 1% and 1.5% of root extract respectively. Various innate immune parameters examined at 14 and 28 days post-feeding. All four Groups of pangus injected intraperitoneally with P. fluorescens (3.2×10-6 CFU ml-1) and after 14 and 28 days of post immunization, bloods sampled collected from live fish with a hypodermic syringe. The present results demonstrated that Dietary supplementation of A. aspera (1.5%) showed significantly increased serum antibody titer (3280), phagocytic activity (49%), immune response as both specific (44%) and non-specific (3%), activation of disease resistance and growth factors (41.1%) of P. pangasius (P

Newcastle disease virus vaccination enhanced severity of Escherichia coli infection in chicken

The present study emphasizes the effect of LaSota vaccination on the experimental E. coli infection in chickens. 160 chicks, 7 day old were divided into four groups of 45 birds each in groups A and group B and 35 birds each in groups C and D. The chicks of groups B and C were given LaSota vaccine by intranasal route @ 106 EID 50 per bird at the age of 7 days. At 15 days age, the chicks of groups A and B were injected with 107 CFU of E. coli O78/chick, intraperitoneally. The chicks of group D were kept as control. The clinical signs such as loss of body weight, anorexia and respiratory distress were more severe in group B. The percent mortality was more in group B (37.7%) as compared to group A (20%). The protective HI (> log24 with 4HA units) titre against New castle disease in both the vaccinated groups was noticed from 15th day post vaccination. The highest HI antibody titre (log2 6.80±0.37) was noticed in group B at 29 DPV. An overall increase in serum antibody titre against E. coli infection was observed in group B as compared to group A. The severity of gross and histopathological changes such as fibrinous pericarditis and perihepatitis was of higher magnitude in group B as compared to group A. It is concluded that administration of NDV LaSota vaccines enhanced the severity of colibacillosis in chickens as evidenced by clinical signs, mortality, immunological response and pathological changes.

Epidemiologic, Virologic, and Host Genetic Factors of Norovirus Outbreaks in Long-term Care Facilities.

In the Unites States, long-term care facilities (LTCFs) are the most common setting for norovirus outbreaks. These outbreaks provide a unique opportunity to better characterize the viral and host characteristics of norovirus disease. We enrolled 43 LTCFs prospectively to study the epidemiology, virology, and genetic host factors of naturally occurring norovirus outbreaks. Acute and convalescent stool, serum, and saliva samples from cases, exposed and nonexposed controls were collected. Norovirus infection was confirmed using quantitative polymerase chain reaction testing of stool samples or 4-fold increase in serum antibody titers. The presence of histo-blood group antigens (secretor, ABO, and Lewis type) was determined in saliva. Sixty-two cases, 34 exposed controls, and 18 nonexposed controls from 10 norovirus outbreaks were enrolled. Forty-six percent of acute, 27% of convalescent case, and 11% of control stool samples tested norovirus positive. Outbreak genotypes were GII.4 (Den Haag, n = 3; New Orleans, n = 4; and Sydney, n = 2) and GI.1 (n = 1). Viral load in GII.4 Sydney outbreaks was significantly higher than in outbreaks caused by other genotypes; cases and controls shed similar amounts of virus. Forty-seven percent of cases shed virus for ≥ 21 days. Symptomatic infections with GII.4 Den Haag and GII.4 New Orleans were detected among nonsecretor individuals. Almost half of all symptomatic individuals shed virus for at least 21 days. Viral load was highest in GII.4 viruses that most recently emerged; these viruses also infect the nonsecretor population. These findings will help to guide development of targeted prevention and control measures in the elderly.

Adjuvant-specific regulation of long-term antibody responses by ZBTB20

The duration of antibody production by long-lived plasma cells varies with the type of immunization, but the basis for these differences is unknown. We demonstrate that plasma cells formed in response to the same immunogen engage distinct survival programs depending on the adjuvant. After alum-adjuvanted immunization, antigen-specific bone marrow plasma cells deficient in the transcription factor ZBTB20 failed to accumulate over time, leading to a progressive loss of antibody production relative to wild-type controls. Fetal liver reconstitution experiments demonstrated that the requirement for ZBTB20 was B cell intrinsic. No defects were observed in germinal center numbers, affinity maturation, or plasma cell formation or proliferation in ZBTB20-deficient chimeras. However, ZBTB20-deficient plasma cells expressed reduced levels of MCL1 relative to wild-type controls, and transgenic expression of BCL2 increased serum antibody titers. These data indicate a role for ZBTB20 in promoting survival in plasma cells. Strikingly, adjuvants that activate TLR2 and TLR4 restored long-term antibody production in ZBTB20-deficient chimeras through the induction of compensatory survival programs in plasma cells. Thus, distinct lifespans are imprinted in plasma cells as they are formed, depending on the primary activation conditions. The durability of vaccines may accordingly be improved through the selection of appropriate adjuvants.

A case of pneumonia caused by Legionella pneumophila serogroup 12 and treated successfully with imipenem

The patient was an 83-year-old man hospitalized for Haemophilus influenzae pneumonia, who developed recurrent pneumonia after improvement of the initial episode. Legionella pneumophila serogroup 12 was isolated from the sputum, accompanied by increased serum antibody titers to L. pneumophila serogroup 12. Therefore, the patient was diagnosed as having Legionella pneumonia caused by L. pneumophila serogroup 12. Case reports of pneumonia caused by L. pneumophila serogroup 12 are rare, and the case described herein is the first report of clinical isolation of this organism in Japan. When the genotype was determined by the protocol of The European Working Group for Legionella Infections (Sequence-Based Typing [SBT] for epidemiological typing of L. pneumophila, Version 3.1), the sequence type was ST68. Imipenem/cilastatin therapy was found to be effective for the treatment of Legionella pneumonia in this patient.

Selective Antibody Response to Streptococcus gallolyticus Pilus Proteins in Colorectal Cancer Patients

Streptococcus gallolyticus subsp. gallolyticus (previously called Streptococcus bovis biotype I) infections have long been associated with colorectal cancer (CRC). This work aimed to investigate the CRC-associated humoral immune response to four pilus proteins of this bacterium by newly developed ELISAs. Pilus proteins are interesting diagnostic targets as they are the building blocks of pilin-like structures that mediate bacterial virulence and are readily exposed to the host immune system upon infection. The presence of serum antibodies against these pilus proteins was evaluated in Dutch and American populations. These analyses showed that an immune response to these antigens was specific for clinical S. gallolyticus subsp. gallolyticus infections, but that increased serum antibody titers to multiple pilus proteins in single individuals were rarely observed. However, a multiplex approach based on antibody titers against any of these four antigens resulted in assay sensitivities between 16% and 43% for the detection of early-stage CRC. Together these findings underscore the potential of a multi-antigen approach to complement diagnosis of S. gallolyticus subsp. gallolyticus-associated CRC.

Vaccination of Llamas, Llama glama, with an Experimental Killed Encephalomyocarditis Virus Vaccine

Encephalomyocarditis virus (EMCV) is a pandemic virus that has caused mortality in numerous captive wildlife species worldwide. An experimental killed vaccine was created from two EMCV isolates associated with zoo animal mortality in the southern United States. The vaccine was tested for safety and efficacy in eleven llamas (Llama glama). All animals received an initial vaccination and a second booster vaccination 4 wk later. Serum antibody responses were monitored at initial vaccination and at 4 wks, 8 wk, 6 mo, and 12 mo postvaccination. Eight of the 11 llamas vaccinated experienced at least a 4-fold increase in serum antibody titers to EMCV. Antibody titers of those eight animals remained elevated above prevaccination levels when measured at 12 mo. The experimental killed EMCV vaccine tested may be a useful tool to prevent EMCV infection in llamas when given in 2 doses 4 wk apart, and then revaccinated or with antibody levels monitored annually thereafter.

Intractable genital ulcers from herpes simplex virus reactivation in drug‐induced hypersensitivity syndrome caused by allopurinol

Drug-induced hypersensitivity syndrome (DIHS/DRESS) is a severe adverse systemic reaction. Reactivation of human herpesvirus (HHV) family members other than HHV-6 has been reported in patients with DIHS. Reactivation of HHV family members is generally characterized by increased serum antibody titers against the virus. By contrast, clinical symptoms caused by viral reactivation are relatively rare. We report a case of DIHS with intractable genital ulcers from reactivation of herpes simplex virus (HSV) in accordance with reactivation of HHV-6 and cytomegalovirus (CMV). Twenty-two days after the onset of the rash, the patient developed intractable genital ulcers that were resistant to treatment. Histological examination of the ulcers revealed necrotic degeneration in the epidermal cells, with giant cells containing inclusion bodies and marked lymphocytic infiltration in the upper dermis. Immunohistochemical staining with antibodies reactive to HSV or CMV showed that these giant cells were positive for HSV but negative for CMV. Genital herpes is a common skin disease. However, our case was considered to be a DIHS-associated symptom, not an accidental complication, as the symptoms were severe and resistant to treatment.