RU2128224C1 - Strain b/60/peterburgh/95/20 for production of living antiinfluenza intranasal vaccine for adults and children - Google Patents

Abstract

FIELD: medicine, virology. SUBSTANCE: invention proposes vaccine for adults and children corresponding to an actual virus B/Peterburgh/92/95 by antigenic properties. Vaccine strain B/60/Peterburgh/95/20 is a reassortant obtained by breeding an epidemic virus B/Peterburgh/92/95 with cold-adapted temperature-sensitive viris B/USSR/60/69 - an attenuation donor. Strain is harmless for adults and children, its properties provide possibility to obtain reassortant vaccine strains from newly appearing epidemic viruses. Strain B/60/Peterburgh/95/20 multiplicates actively in developing chicken embryos at optimal temperature 32-33 C and shows temperature-sensitivity and cold-adaptation. Reassortant inherited two genes encoding surface proteins (hemagglutinin and neuraminidase) from an epidemic virus and six genes encoding nonglycosylated proteins from an attenuation donor. Strain B/60/Peterburgh is nonreactive for adults and children (3-14 years age) at intranasal administration and corresponds to immunogenicity indices. Vaccine strain B/60/Peterburgh/95/20 by its biological properties and reactive indices corresponds to requirements for vaccine strains by Pharmacopoeia articles FS 42-298 BS-89 and FS 42-299 VS-89 for living antiinfluenza vaccine for intranasal using for children (3-14 years age) and living antiinfluenza vaccine for intranasal using for adults. EFFECT: strain indicated above. 2 tbl, 2 ex

Description

 The invention relates to medical virology and can be used in healthcare for the prevention of epidemic influenza among adults and children with a live intranasal influenza vaccine from strain B / 60 / Petersburg / 95/20. The known vaccine strain B / 60/32 / P of the influenza B virus - the prototype [1] - has lost antigenic relevance and therefore cannot cause a protective reaction during the epidemic caused by modern strains of the influenza B virus.

 The problem to which the invention is directed, is to obtain a vaccine strain of the actual antigenic variety based on the epidemic virus B / Petersburg / 92/95.

 The vaccine strain B / 60 / Petersburg / 95/20 was obtained by genetic reassortment of the epidemic virus B / Petersburg / 92/95 with a cold-adapted strain B / USSR / 60/69 - an attenuation donor - followed by selection in the presence of antiserum for virus B / USSR / 60/69. The attenuation donor B / USSR / 60/69 is a cold-adapted temperature-sensitive strain of influenza virus that is approved for the production of harmless live intranasal vaccines for adults and children [2].

Using a comparative analysis of the electrophoretic mobility of RNA fragments of parent viruses and reassortant clones in polyacrylamide gels, it was found that vaccine strain B / 60 / Petersburg / 95/20 inherited 6 genes encoding internal proteins (PB1, PB2, PA, NP, M, NS) from attenuation donor, and 2 genes encoding surface proteins - HA (hemagglutinin) and NA (neuraminidase) - from the epidemic virus. The strain is temperature-sensitive (titer difference at 33 ^o C and 39 ^o C - 6.0 lg EID ₅₀ / 0.2 ml) and cold-adapted (titer difference at 33 ^o C and 25 ^o C - 4.0 lg EID ₅₀ / 0.2 ml )

 Thus, the presented vaccine strain B / 60 / Petersburg / 95/20 is characterized by a combination of useful features necessary for the vaccine strain - the antigenicity of the surface proteins of the epidemic virus B / Petersburg / 92/95, the genome structure optimal for reassortant vaccine strains, temperature sensitivity and cold adaptation , which correlates with attenuation for a person characteristic of an attenuation donor.

 The morphology of the strain is polymorphic, typical of the influenza virus.

STRAIN CHARACTERISTIC
Infectious activity during reproduction in developing chicken embryos at 33 ^o C for 72 hours - 7.5 lg EID ₅₀ / 0.2 ml

 Hemagglutinating activity -1: 256.

 The strain exhibits genetic stability of biological traits after 5 passages on chicken embryos (when using large infectious doses).

 The data from the passport for the vaccine strain B / 60 / Petersburg / 95/20 are given below.

1. The name of the strain is B / 60 / Petersburg / 95/20
2. Series - Series 1
3. The method of production and characterization of parent viruses when presenting a recombinant strain: recombination
a). epidemic virus - B / Petersburg / 92/95
b) attenuation donor - B / USSR / 60/69
4. The number of passages - 7 in the process of recombination
5. Characterization of the strain:
a). optimal conditions for reproduction - 33 ^o C, 72 hours;
b) hemagglutinating activity - 1: 256;
in). infectious activity - 7.5 lg EID ₅₀ / 0.2 ml;
d). sensitivity to inhibitors - inhibitory-sensitive;
e). the difference in indicators of infectious activity at 33 ^o C and 39 ^o C - 6.0 lg EID ₅₀ / 0.2 ml:
e). the difference in the indicators of infectious activity at 33 ^o C and 25 ^o C - 4.0 lg EID ₅₀ / 0.2 ml

g). recombinant genome structure:
- genes for the epidemic virus- HA, NA
- genes from an attenuation donor - RA, PB1, PB2, NP, M, NS
6. Characterization of the strain after lyophilization:
a). lyophilization date - July 8, 1996:
b) the volume of material in the ampoule is 1 ml;
in). the number of doses in the series - 3;
d). infectious activity - 7.0 lg EID ₅₀ /0.2 ml;
e). hemagglutinating activity -1: 128.

 7. The recommended dilution for vaccination is 1: 3.

8. Antigenic specificity
a). hemagglutinin in rtga - identical to virus B / Petersburg / 92/95, the antiserum of which is completely neutralized;
b) neuraminidase - identical to virus B / Petersburg / 92/95 according to polyacrylamide gel electrophoresis.

 9. Harmless to mice by subcutaneous administration - harmless.

10. Bacteriological control of lyophilized material: date of conduct - July 26, 1996
the result is sterile.

 11. Control for the absence of extraneous viruses - extraneous viruses are absent.

 1. Strain B / 60 / Petersburg / 95/20 arereactogenic and immunogenic for the adult population.

Example 1. When vaccinating 72 adults with an intranasally recombinant vaccine strain B / 60 / Petersburg / 95/20 with an infectious activity of 7.5 lg EID ₅₀ / 0.2 ml in a dilution of 1: 2 in a volume of 0.5 ml of strong temperature reactions with an increase in temperature above 38.5 ^o C was not observed. Medium reactions with a short-term temperature increase in the range of 37.6-38.5 ^o C were observed in 1.4%. Weak temperature reactions (up to 37.5 ^o C) were observed in 1.4% of cases. The reactogenicity index (the difference in the percentage of average reactions in vaccinated vaccines and received placebo) was 0%. The survey results are shown in table 1.

 In the group of 77 individuals who received a placebo, average temperature reactions were observed in 6.5%, weak reactions were also observed in 6.5% of cases.

 When studying the serum of 47 seronegative vaccinated individuals in the RTGA reaction, a 4-fold or more increase in serum antibodies to the epidemic strain B / 60 / Petersburg / 95/20 was found in 63.8% of cases. Geometric mean antibody titers in second sera in individuals with 4-fold or more antibody growths were 1: 30.3.

 Thus, the vaccine strain B / 60 / Petersburg / 95/20 in terms of reactogenicity and immunogenicity complies with the requirements of pharmacopoeial article FS 42-299 BC-89 for vaccine strains for live influenza vaccine for intranasal use for adults.

 2. Strain B / 60 / Petersburg / 95/20 isreactogenic with intranasal administration to children 3-14 years old.

Example 2. A group of 103 children aged 3-14 years old were vaccinated intranasally in a volume of 0.5 ml with the recombinant vaccine strain B / 60 / Petersburg / 95/20 with an infectious activity of 7.5 lg EID ₅₀ / 0.2 ml diluted 1: 2. A group of children of the same age out of 89 received a placebo. The research results are shown in table 2.

In the group of vaccinated children, strong temperature reactions with a temperature increase above 38.5 ^o C were not observed. Average reactions in the range of 37.6-38.5 ^o C were also not observed. The reactogenicity index was 0%. Weak temperature reactions with a short-term increase in temperature to 37.5 ^o C - in 3.9% of cases.

In the group of children who received a placebo, strong temperature reactions with fever above 38.5 ^o C were not observed. Average temperature reactions were observed in 1.1%, and weak ones in 3.4% of cases.

 Thus, the vaccine strain B / 60 / Petersburg / 95/20 in terms of reactogenicity complies with the requirements for vaccine strains with pharmacopeia article FS 42-298 BC-89 for live influenza vaccine for intranasal use in children 3-14 years old.

LITERATURE
1. Strain B / 60/32 / P of influenza B virus used to produce live intranasal vaccine for adults and children. Author's certificate N1731811, published 07.05.92 BI N17 for 1992

 2. Alexandrova G.I., Klimov A.I. Live flu vaccine. - SPb .: Science. -1994. -151 p.

Claims (1)

 The strain of the influenza virus I / 60 / Petersburg / 95/20 GISK N 1003 (State Institute of Standardization and Control named after L.A. Tarasevich), used to obtain live influenza intranasal vaccine for adults and children.

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