Heterologous priming–boosting with DNA and vaccinia virus expressing kinetoplastid membrane protein-11 induces potent cellular immune response and confers protection against infection with antimony resistant and sensitive strains of Leishmania (Leishmania) donovani

The Evaluation of the immune response in Golden Hamsters experimentally infected with Leishmania donovani was determined in this study, particularly, the cellular immune response. Follow up has maintained to determine the Delayed Type of Hypersensitivity using skin test both in infected and control lab animals. Chicken red blood cells were used as a parameter to evaluate the immune system; they are dull and have the ability of immunization. Two concentrations of chicken R.B.C were examined to determine which gives the higher titration in Hamsters and those were 1.5 X 109 cell/ml and 3 X 109 cell/ml , the second concentration gave the maximum titration where then used in this work. After sensitization with Chicken R.B.C for both infected and control groups, delayed type of hypersensitivity has been used against Leishmania donovani antigen and 4 days of follow up were adopted and they were (14, 30, 60, 90) day after infection. Results showed that skin test against both antigens ( L.donovani and chicken R.B.C) was significantly higher than normal at the first day of follow up ( day 14) then gradual decreasing were noticed till the last day of follow up (90). This can indicate that the infection with L.donovani activated the immune response at the beginning of infection, then leads to cellular immune suppression against both L.donovani antigen and chicken R.B.C., so that this immunosuppression is not specific.

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Genes that control vaccinia virus immunogenicity

Acta Naturae ◽

10.32607/actanaturae.10935 ◽

2020 ◽

Vol 12 (1) ◽

pp. 33-41 ◽

Cited By ~ 2

Author(s):

Sergey Shchelkunov ◽

G. A. Shchelkunova

Keyword(s):

Immune Response ◽

Side Effects ◽

Genetic Engineering ◽

Vaccinia Virus ◽

Cellular Immune Response ◽

Human Population ◽

Effective Vaccine ◽

Global Eradication ◽

Cellular Immune ◽

High Immunogenicity

The live smallpox vaccine was a historical first and highly effective vaccine. However, along with high immunogenicity, the vaccinia virus (VACV) caused serious side effects in vaccinees, sometimes with lethal outcomes. Therefore, after global eradication of smallpox, VACV vaccination was stopped. For this reason, most of the human population worldwide lacks specific immunity against not only smallpox, but also other zoonotic orthopoxviruses. Outbreaks of diseases caused by these viruses have increasingly occurred in humans on different continents. However, use of the classical live VACV vaccine for prevention against these diseases is unacceptable because of potential serious side effects, especially in individuals with suppressed immunity or immunodeficiency (e.g., HIV-infected patients). Therefore, highly attenuated VACV variants that preserve their immunogenicity are needed. This review discusses current ideas about the development of a humoral and cellular immune response to orthopoxvirus infection/vaccination and describes genetic engineering approaches that could be utilized to generate safe and highly immunogenic live VACV vaccines.

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