Oviduct Infection and Hydrosalpinx in DBA1/j Mice Is Induced by Intracervical but Not Intravaginal Inoculation with Chlamydia muridarum

Intravaginal infection with C. muridarum in mice often results in hydrosalpinx similar to that found in women urogenitally infected with C. trachomatis, making the C. muridarum lower genital tract infection murine model suitable for studying C. trachomatis pathogenesis. To our surprise, DBA1/j mice were highly resistant to hydrosalpinx following an intravaginal infection with C. muridarum although these mice were as susceptible to lower genital tract infection as other mouse strains. A significantly lower level of C. muridarum organisms was recovered from the oviduct of DBA1/j mice, correlating the resistance to hydrosalpinx with reduced ascension of C. muridarum to the oviduct. The DBA1/j resistance to hydrosalpinx was effectively overcome by intracervical inoculation with C. muridarum. The intracervically inoculated DBA1/j mice developed severe hydrosalpinx with the highest levels of live C. muridarum organisms recovered from uterine tissue on day 3 and oviduct tissue on day 7 post inoculation while in intravaginally inoculated DBA1/j mice, the peak of live organism recovery from uterine tissue was delayed to day 7 with no rise in the amount of live organisms recovered from the oviduct. These observations have not only validated the correlation between hydrosalpinx and live organism invasion in the oviduct but also demonstrated that the intracervical inoculation, by promoting rapid chlamydial replication in the uterine epithelial cells and ascension to the oviduct of DBA1/j mice, may be used for further understanding chlamydial pathogenic mechanisms. The above findings also suggest that strategies aimed at reducing tubal infection may be most effective in blocking tubal pathology.     

Growth Curve and Distribution of Rous Sarcoma Virus (Bryan) in Japanese Quail

On primary infection with the Bryan strain of Rous sarcoma virus (RSV), the growth curve of the virus in the brain of Japanese quail was similar to that observed in chicks and turkey poults. Infectious virus disappeared from the brain after inoculation. After an eclipse period during which no virus was detectable, infectious virus began to appear at 2 days and reached maximal titers in the brain samples at 7 days after inoculation. When Japanese quail were infected intracerebrally with RSV, relatively high titers of virus were recovered from brain tissue but not from liver, lung, kidney, or blood of moribund birds. Only tumors produced in the wing web of quail infected subcutaneously yielded high titers of virus. Other tissues yielded no virus, even though wing web tumors appeared as early as in chicks similarly infected. RSV could be propagated in the wing web of quail for at least 14 passages without any loss of infectivity. On the other hand, serial passage in quail brain resulted in a progressive loss of infectivity until virus was completely lost.     

Blastogenic responsiveness of spleen cells fromLegionella pneumophila-infected mice immunosuppressed with cyclophosphamide

Although guinea pigs are highly susceptible to experimental infection withLegionella pneumophila, mice are considered resistant. In the present study it was found that, although untreated mice resisted lethal infection with up to 10⁷ L. pneumophila, mice treated with three divided doses of cyclophosphamide became 10–100 times more susceptible. Injection of mice with 150 mg cyclophosphamide/kg body weight 96 and 48h prior to and on the same day as intraperitoneal challenge with graded dose ofL. pneumophila resulted in markedly increased lethality. Approximately half of the mice pretreated with cyclophosphamide succumbed to 10⁶ legionellae within 4–10 days after infection, and all treated animals given 10⁷ bacteria died. Legionellae were readily recovered from spleen, lymph nodes, and liver of surviving mice 4–10 days after infection, but not thereafter. Sensitization of mice with Legionella antigen was evident by the lymphocyte blastogenic test in vitro, by use of spleen cells at various times after infection. Mice given graded doses ofL. pneumophila evinced enhanced responsiveness to either formalin-killed whole cell vaccine, cell-free sonicate, or purified outer membrane antigen when tested in vitro on days 3 and 5. Peak responses generally occurred 20–35 days after infection. Mice given none or one dose of cyclophosphamide and injected with legionellae showed enhanced responses on day 5 of culture in vitro, a time when spleen cells from control nonsensitized animals showed much lower responses. Surviving mice given three doses of cyclophosphamide had lower blastogenic responses, generally as low as that occurring with spleen cells from nonsensitized animals. Thus suppression of immune responses of mice by cyclophosphamide substantially increased susceptibility toL. pneumophila and depressed blastogenic responsiveness.     

A Hematogenously Disseminated Orientia tsutsugamsushi-Infected Murine Model of Scrub Typhus

Orientia tsutsugamushi, the etiologic agent of scrub typhus, is a mite-borne rickettsia transmitted by the parasitic larval stage of trombiculid mites. Approximately one-third of the world''s population is at risk of infection with Orientia tsutsugamushi, emphasizing its importance in global health. In order to study scrub typhus, Orientia tsutsugamushi Karp strain has been used extensively in mouse studies with various inoculation strategies and little success in inducing disease progression similar to that of human scrub typhus. The objective of this project was to develop a disease model with pathology and target cells similar to those of severe human scrub typhus. This study reports an intravenous infection model of scrub typhus in C57BL/6 mice. This mouse strain was susceptible to intravenous challenge, and lethal infection occurred after intravenous inoculation of 1.25×10⁶ focus (FFU) forming units. Signs of illness in lethally infected mice appeared on day 6 with death occurring ∼6 days later. Immunohistochemical staining for Orientia antigens demonstrated extensive endothelial infection, most notably in the lungs and brain. Histopathological analysis revealed cerebral perivascular, lymphohistiocytic infiltrates, focal hemorrhages, meningoencephalitis, and interstitial pneumonia. Disseminated infection of endothelial cells with Orientia in C57BL/6 mice resulted in pathology resembling that of human scrub typhus. The use of this model will allow detailed characterization of the mechanisms of immunity to and pathogenesis of O. tsutsugamushi infection.     

Towards the Conservation of Endangered Avian Species: A Recombinant West Nile Virus Vaccine Results in Increased Humoral and Cellular Immune Responses in Japanese Quail (Coturnix japonica)

West Nile Virus (WNV) arrived in North America in 1999 and is now endemic. Many families of birds, especially corvids, are highly susceptible to WNV and infection often results in fatality. Avian species susceptible to WNV infection also include endangered species, such as the Greater Sage-Grouse (Centrocercus uropbasianuts) and the Eastern Loggerhead Shrike (Lanius ludovicianus migrans). The virus has been shown to contribute towards the likelihood of their extinction. Although a clear and present threat, there exists no avian WNV vaccine available to combat this lethal menace. As a first step in establishing an avian model for testing candidate WNV vaccines, avian antibody based reagents were assessed for cross-reactivity with Japanese quail (Coturnix japonica) T cell markers CD4 and CD8; the most reactive were found to be the anti-duck CD8 antibody, clone Du-CD8-1, and the anti-chicken/turkey CD4 antibody, clone CT4. These reagents were then used to assess vaccine performance as well as to establish T cell populations in quail, with a novel population of CD4/CD8 double positive T cells being identified in Japanese quail. Concurrently, non-replicating recombinant adenoviruses, expressing either the WNV envelope or NS3 ‘genes’ were constructed and assessed for effectiveness as avian vaccines. Japanese Quail were selected for testing the vaccines, as they provide an avian model that parallels the population diversity of bird species in the wild. Both the level of WNV specific antibodies and the number of T cells in vaccinated birds were increased compared to unvaccinated controls. The results indicate the vaccines to be effective in increasing both humoral and cellular immune responses. These recombinant vaccines therefore may find utility as tools to protect and maintain domestic and wild avian populations. Their implementation may also arrest the progression towards extinction of endangered avian species and reduce the viral reservoir that potentiates infection in humans.     

Cultivation of Eimeria tenella in Japanese quail embryos (Coturnix coturnix japonica).

Complete development of Eimeria tenella in Japanese quail embryos was observed. Sporozoites were inoculated into the allantoic cavity of 7-day-old Japanese quail embryos (Coturnix coturnix japonica), after which the infected embryos were incubated at 41 C. In the chorioallantoic membrane mature first generation schizonts, mature second generation schizonts, and gametes were detected at 48 hr postinoculation of sporozoites (PI), 84 hr PI, and 126 hr PI, respectively. Mature gametes and zygotes were found at 132 hr PI, and oocysts were detected at 138 hr PI. Mortality of embryos increased with increment of inoculum size of sporozoites. LD50 was 1.7 x 10(2) sporozoites. Oocyst production was also dependent on inoculum size. Oocysts harvested from embryos sporulated. The oocysts were inoculated into 13-day-old chickens, and oocysts, capable of sporulating normally, were recovered from ceca 7 days after inoculation.     

West Nile Virus Infection in American Robins: New Insights on Dose Response

West Nile virus (WNV) is a vector-borne pathogen that was first detected in the United States in 1999. The natural transmission cycle of WNV involves mosquito vectors and avian hosts, which vary in their competency to transmit the virus. American robins are an abundant backyard species in the United States and appear to have an important role in the amplification and dissemination of WNV. In this study we examine the response of American robins to infection with various WNV doses within the range of those administered by some natural mosquito vectors. Thirty American robins were assigned a WNV dosage treatment and needle inoculated with 10^0.95 PFU, 10^1.26 PFU, 10^2.15 PFU, or 10^3.15 PFU. Serum samples were tested for the presence of infectious WNV and/or antibodies, while oral swabs were tested for the presence of WNV RNA. Five of the 30 (17%) robins had neutralizing antibodies to WNV prior to the experiment and none developed viremia or shed WNV RNA. The proportion of WNV-seronegative birds that became viremic after WNV inoculation increased in a dose dependent manner. At the lowest dose, only 40% (2/5) of the inoculated birds developed productive infections while at the highest dose, 100% (7/7) of the birds became viremic. Oral shedding of WNV RNA followed a similar trend where robins inoculated with the lower two doses were less likely to shed viral RNA (25%) than robins inoculated with one of the higher doses (92%). Viremia titers and morbidity did not increase in a dose dependent manner; only two birds succumbed to infection and, interestingly, both were inoculated with the lowest dose of WNV. It is clear that the disease ecology of WNV is a complex interplay of hosts, vectors, and viral dose delivered.     

Day-night rhythms in opiate modulation of body temperature in male Japanese quail

Summary Male Japanese quail,Coturnix coturnix japonica, displayed day-night rhythms in their body temperature, with significantly higher temperatures during the day than at night. There were individual variations in both the temperatures attained and amplitude of the day-night rhythm of body temperature in the group-housed birds. Accompanying these diurnal patterns in body temperature there were day-night rhythms in the effects of intraperitoneal administrations of the opiate agonist, morphine (1.0 and 10 mg·kg^-1) and prototypic opiate antagonist, naloxone (10 mg·kg^-1) on colonic body temperature. In the daytime, the body temperature response profiles of quail treated with morphine were dependent on the initial body temperature of the bird. In those birds with the lower daytime body temperatures, morphine caused an initial hyperthermic response that was followed by a hypothermia and then a weak hyperthermia; whereas, in birds with the higher initial body temperatures there was a pronounced hypothermia followed by a marked hyperthermia. At night, morphine induced a hyperthermic response in all quail that was followed by a hypothermia. These effects of morphine were blocked by naloxone, with naloxone by itself significantly decreasing the daytime temperature of those quail with the higher initial body temperature. Naloxone had no significant effects on the nighttime body temperatures of any of the quail. These results show that there are day-night rhythms and individual differences in opiate sensitivity and modulation of body temperature in male quail. These findings also suggest that endogenous opioid systems are involved in either the generation and/or expression of the day-night rhythm of body temperature in quail.Abbreviations LD light-dark - T _L low initial body temperatures - T _H high initial body temperatures     

Effects of Leaf Age, Inoculum Dose and Freezing on Development of Chocolate Spot (Botrytis fabae) Lesions on Field Bean (Vicia faba) Leaves

Botrytis fabae spore suspensions containing c. 1, 10, 10², 10³, 10⁴, 10⁵, or 10⁶ spores/ml were used to inoculate 5, 17 or 30-day-old field bean leaves. The percentages of the leaf areas covered by, chocolate spot lesions and the percentages of the leaf areas bearing conidiophores were assessed 1, 6, 12, 14, and 19 days after inoculation. The percentage of the area covered by lesions and the percentage of the area bearing conidiophores (logit-transformed) increased linearly with increasing spore concentration (log₁₀-transformed). The proportions of leaf areas covered by lesions and bearing conidiophores were both greater on 17 and 30-day-old leaves than on 5-day-old leaves. The rate of lesion growth increased with both increasing inoculum dose and increasing leaf age. Generally there was no interaction between the effects of leaf age and the effects of inoculum dose on either lesion growth or sporulation. Two days after inoculation with suspensions of either 10⁴ or 10⁶ spores/ml, 7-day-old leaves grown at 15°C were transferred to –16°C or 2.5°C or kept at 15°C for 4 days. Two days later more spores had been produced on leaves which had been frozen (–16°C) than on, leaves kept at 2.5°C.     

Bioluminescence Imaging of Chlamydia muridarum Ascending Infection in Mice

Chlamydial pathogenicity in the upper genital tract relies on chlamydial ascending from the lower genital tract. To monitor chlamydial ascension, we engineered a luciferase-expressing C. muridarum. In cells infected with the luciferase-expressing C. muridarum, luciferase gene expression and enzymatic activity (measured as bioluminescence intensity) correlated well along the infection course, suggesting that bioluminescence can be used for monitoring chlamydial replication. Following an intravaginal inoculation with the luciferase-expressing C. muridarum, 8 of 10 mice displayed bioluminescence signal in the lower with 4 also in the upper genital tracts on day 3 after infection. By day 7, all 10 mice developed bioluminescence signal in the upper genital tracts. The bioluminescence signal was maintained in the upper genital tract in 6 and 2 mice by days 14 and 21, respectively. The bioluminescence signal was no longer detectable in any of the mice by day 28. The whole body imaging approach also revealed an unexpected airway infection following the intravaginal inoculation. Although the concomitant airway infection was transient and did not significantly alter the genital tract infection time courses, caution should be taken during data interpretation. The above observations have demonstrated that C. muridarum can not only achieve rapid ascending infection in the genital tract but also cause airway infection following a genital tract inoculation. These findings have laid a foundation for further optimizing the C. muridarum intravaginal infection murine model for understanding chlamydial pathogenic mechanisms.     

Studies on clinical signs and haematological alterations in pneumonic aspergillosis due to Aspergillus flavus in Japanese quail

Intratracheal inoculation of 2-week old quail chicks with Aspergillus flavus spores resulted in the development of clinical signs within 24 h of infection. These were characterized by dullness, depression, anorexia, accelerated breathing, gasping and prostration leading to death. These signs continued up to 7 days followed by considerable decrease in the intensity of the symptoms as well as number of birds showing clinical signs. Mortality occurred primarily in the first week with a majority of the birds dying from 2–4 days after infection. The overall mortality during a 6-week observation period was 25%. The average body weight of the infected chicks was slightly lower than that of controls; the difference being significant at 2, 3 and 42 days post-infection. There was no appreciable difference in the mean values of haemoglobin, packed cell volume and total erythrocyte count between the infected and control chicks at any stage of infection, but total leucocyte count revealed a significant increase (p<0.05) from 3–7 days post-infection. This was due to increase in the percentage of heterophils and decrease in lymphocytes.     

鹌鹑源鼠伤寒沙门氏菌的分离鉴定与耐药性分析

【背景】在鹌鹑养殖过程中,抗菌药物和消毒剂的不规范使用加剧了耐药菌株在动物、场所和食品之间的相互传播,因此,掌握致病菌株在养殖动物中的耐药状况至关重要。【目的】检测北京周边地区鹌鹑蛋源致病菌株的耐药特征和耐药基因的流行情况。【方法】在天津市武清区部分鹌鹑养殖场采集鹌鹑泄殖腔粪便、鹌鹑蛋表、养殖环境和鹌鹑饮水的样品,通过细菌分离培养、菌落形态观察、染色镜检、生化鉴定、血清分型、沙门氏菌inv A基因序列测定等方法对分离菌株进行鉴定。同时进行小鼠攻毒试验,测定小鼠半数致死量(median lethal dose, LD50)。再通过药敏试验和PCR方法对分离菌的耐药表型、耐药基因及毒力基因进行检测。【结果】分离菌株菌落颜色、镜检形态和生化试验结果符合沙门氏菌特性,沙门氏菌inv A基因序列测定与鼠伤寒沙门氏菌参考株相似度为99.44%,鉴定为鼠伤寒沙门氏菌,血清型为1,4,[5],[12]:i:l,2。该菌株对小鼠有致病作用,小鼠LD50为2.10×107 CFU/mL;药敏试验结果显示该菌株对氨苄西林、阿莫西林/克拉维酸、头孢噻呋、链霉素、磺胺甲啞唑、磺胺异啞唑、诺氟沙星、环丙沙星表现耐...     

Poxvirus Antigen Staining of Immune Cells as a Biomarker to Predict Disease Outcome in Monkeypox and Cowpox Virus Infection in Non-Human Primates

Infection of non-human primates (NHPs) such as rhesus and cynomolgus macaques with monkeypox virus (MPXV) or cowpox virus (CPXV) serve as models to study poxvirus pathogenesis and to evaluate vaccines and anti-orthopox therapeutics. Intravenous inoculation of macaques with high dose of MPXV (>1–2×10⁷ PFU) or CPXV (>10² PFU) results in 80% to 100% mortality and 66 to 100% mortality respectively. Here we report that NHPs with positive detection of poxvirus antigens in immune cells by flow cytometric staining, especially in monocytes and granulocytes succumbed to virus infection and that early positive pox staining is a strong predictor for lethality. Samples from four independent studies were analyzed. Eighteen NHPs from three different experiments were inoculated with two different MPXV strains at lethal doses. Ten NHPs displayed positive pox-staining and all 10 NHPs reached moribund endpoint. In contrast, none of the three NHPs that survived anticipated lethal virus dose showed apparent virus staining in the monocytes and granulocytes. In addition, three NHPs that were challenged with a lethal dose of MPXV and received cidofovir treatment were pox-antigen negative and all three NHPs survived. Furthermore, data from a CPXV study also demonstrated that 6/9 NHPs were pox-antigen staining positive and all 6 NHPs reached euthanasia endpoint, while the three survivors were pox-antigen staining negative. Thus, we conclude that monitoring pox-antigen staining in immune cells can be used as a biomarker to predict the prognosis of virus infection. Future studies should focus on the mechanisms and implications of the pox-infection of immune cells and the correlation between pox-antigen detection in immune cells and disease progression in human poxviral infection.     

Interference of anti-tumor and immunosuppressive effects of cyclophosphamide in tumor-bearing rats

Summary Adult rats were given 10⁵ or 10⁶ Yoshida ascites sarcoma (YAS) cells IP and were treated with cyclophosphamide (CY) given IP in single doses of 20 mg/kg or 100 mg/kg, 2 or 5 days after YAS inoculation. Both the curative effect of CY and subsequent resistance to tumor challenge in rats that survived depended on the dose of injected tumor cells and on the dose and time of administration of CY. These three factors determined whether the host's immune response to tumor antigens would develop and contribute to the overall anti-tumor effects of the chemotherapy. The curative effects of CY were significantly less pronounced in T-cell-deficient than in normal rats. Anti-tumor and immunosuppressive activities of CY exerted opposite influences on the ultimate result of the chemotherapy. Adverse immunosuppressive effects prevailed when the drug was administered early (2 days) after YAS inoculation. In this case the chemotherapy was less efficient and the surviving rats were susceptible to a subsequent tumor challenge. Further analysis showed that the injection of CY 2 days after inoculation of YAS antigens induced strong and specific immunologic tolerance to the tumor. In contrast, when a sufficient amount of tumor antigens (higher dose of tumor cells injected and CY injection delayed) elicited an anti-YAS immune response that was not suppressed by early injection of CY (CY administered 5 days after the tumor) effective eradication of tumor cells and anti-YAS resistance in cured animals were observed.Abbreviations YAS Yoshida ascites sarcoma - CY cyclophosphamide - MRBC mouse red blood cells     

Eimeria acervulina: The influence of inoculation dose on transmission between broiler chickens

The course and clinical appearance of an Eimeria species infection in chicken flocks depend on the response of an individual bird to infection and on population-dynamics of the infection in the flock. Differences in ingested numbers of oocysts may affect oocyst load in the flock and the subsequent infectious dose for not yet infected birds. To study the link between numbers of oocysts excreted by infected birds and transmission of Eimeria acervulina, experiments were carried out with 42 pairs of broiler chickens using inoculation doses with 5, 50, 500 or 50,000 sporulated oocysts. In each pair one bird was inoculated and the other bird was contact-exposed. All contact birds became infected, which occurred on average within 34 h after exposure to an inoculated bird. Although a higher inoculation dose resulted in higher oocyst excretion in inoculated and contact-infected birds, only small non-significant differences in transmission rates between groups were found.     

An experimental model for studying radiation-induced suppression of antitumor resistance

In experiments on mice (CBA × C57Bl)F₁ an experimental model is developed for studying the effect of radiation on antitumor resistance. Adequate ways are offered for statistical processing of the data on enhancement of tumor growth in the irradiated organism. The validated model is a solid tumor developing after inoculation of a mouse with 1000 cells of Ehrlich ascites tumor into a hind shin, combined with suppression of antitumor resistance upon a 6-Gy (¹³⁷Cs) whole-body exposure. The recommended parameters for assessing tumor growth are: share of animals with tumors by day 30 after inoculation, length of the latent period, probability of tumor development, and tumor volume by day 30. For data processing, besides the common Fisher, χ² and Mann-Whitney tests, we recommend the Kaplan-Meier method and Log-rank. The proposed model can be a reliable tool in solving problems at the junction of radiobiology, oncology, immunology, pharmacology, etc.     

Marrow-dependent cell function in early stages of infection with Listeria monocytogenes.

Mice were infected with either Listeria monocytogenes (LM) or Yersinia pestis EV 76 stain (YP), which are facultative intracellular and extracellular organisms, respectively. Bacterial growth in spleen was determined at various intervals following challenge, focusing particularly on the critical period prior to the emergence of specific immunity. Natural resistance to LM during the first 2 days was diminished by treatment of adult mice with ⁸⁰Sr or silica particles, but not by treatment with lethal total-body irradiation, cortisol, or cyclophosphamide (CY). Early stages of resistance to YP were unaffected by ⁸⁰Sr, but were reduced by lethal total-body irradiation, silica particles, cortisol, and (CY). Infant mice manifested no resistance comparable to that of adults against LM prior to 19 days of age, whereas resistance against YP was attained by 14 days of age. The data are consistent with the hypothesis that marrow-dependent (M) cells function in host defense against early stages of infection with LM but not with YP.     

Effect of trypsinization on susceptibility of primary human amniotic cells toChlamydia trachomatis TW-3 strain

The effect of trypsinization of human amnion membranes on the susceptibility of amnion cells toChlamydia trachomatis TW-3 infection was examined by infectivity titrations using standard procedures of chlamydial inoculation, and detection of chlamydial inclusions. Epithelial cells derived from freshly trypsinized membranes as well as primary and secondary cultured cells that were freshly removed from monolayers by trypsin treatment were not susceptible to infection at 30 min and at 2 and 6 h after trypsinization. Monolayers grown 18 h and up to 5 or more days after trypsinization were susceptible to infection. Primary 5-day monolayers derived from each of nine placentas inoculated with chlamydiae showed a range of titers from 10⁻³ to 10^−6.5 (SD=1.2 logarithm). Primary monolayers supported the multiplication of chlamydiae to consistently higher titers than secondary and tertiary monolayers from the same amnion.     

Evidence for introgressive hybridization of wild common quail (Coturnix coturnix) by domesticated Japanese quail (Coturnix japonica) in France

Many cases of introgressive hybridization have been reported among birds, particularly following introduction to the natural environment of individuals belonging to non-native similar taxa. This appears to be the case for common quail (Coturnix coturnix) in France where wild populations artificially come into contact with domesticated Japanese quail (Coturnix japonica) raised for meat and egg production but sometimes released for hunting purposes. In order to highlight the possible existence of gene flows between both taxa, a comparison of nuclear (25 microsatellite loci) and mitochondrial (sequencing and RFLP) DNA polymorphisms was performed on 375 common quails (from France, Spain and Morocco) and 140 Japanese quails (from France and Japan). Genetic diversity was assessed, and analyses (Factorial Correspondence Analysis, Bayesian admixture) of molecular polymorphisms revealed clear differentiation between the two taxa, making it possible to detect for hybrids among quails sampled in the wild. Eight birds expected to be common quail were found to be two pure Japanese quail, one probable backcross to C. japonica, three F1/F2 hybrids, and two probable backcrosses to Coturnix coturnix. These results show that Japanese quails were released and suggest that the two taxa hybridize in the wild. They confirm the urgent need for preventing the release of pure Japanese or hybrid quails to preserve the genetic integrity of C. coturnix. The tools developed for this study should be useful for accurate monitoring of wild quail populations within the framework of avifauna management programs.     

Effect of AcHERV-GmCSF as an Influenza Virus Vaccine Adjuvant

Introduction

The first identification of swine-originated influenza A/CA/04/2009 (pH1N1) as the cause of an outbreak of human influenza accelerated efforts to develop vaccines to prevent and control influenza viruses. The current norm in many countries is to prepare influenza vaccines using cell-based or egg-based killed vaccines, but it is difficult to elicit a sufficient immune response using this approach. To improve immune responses, researchers have examined the use of cytokines as vaccine adjuvants, and extensively investigated their functions as chemoattractants of immune cells and boosters of vaccine-mediated protection. Here, we evaluated the effect of Granulocyte-macrophage Colony-Stimulating Factor (GmCSF) as an influenza vaccine adjuvant in BALB/c mice.

Method and Results

Female BALB/c mice were immunized with killed vaccine together with a murine GmCSF gene delivered by human endogenous retrovirus (HERV) envelope coated baculovirus (1×10⁷ FFU AcHERV-GmCSF, i.m.) and were compared with mice immunized with the killed vaccine alone. On day 14, immunized mice were challenged with 10 median lethal dose of mouse adapted pH1N1 virus. The vaccination together with GmCSF treatment exerted a strong adjuvant effect on humoral and cellular immune responses. In addition, the vaccinated mice together with GmCSF were fully protected against infection by the lethal influenza pH1N1 virus.

Conclusion

Thus, these results indicate that AcHERV-GmCSF is an effective molecular adjuvant that augments immune responses against influenza virus.