RU2307162C1 - Influenza virus strain for influenza intranasal vaccine for infants and adults - Google Patents

Abstract

FIELD: virology, immunology.

SUBSTANCE: vaccine strain is obtained by cross-breed of specific epidemic virus with cold-adapted temperature-sensitive virus as attenuation donor. Strain actively multiplies in developing hen embryos at optimal temperature of 33°C and is characterized with cold-adaptation and temperature-sensitivity. Strain has genes from epidemic virus encoding hemagglutinin and neuraminidase and six genes from attenuation donor encoding non-glycosilated proteins.

EFFECT: new strain for living influenza intranasal vaccine for infants and adults.

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Description

The invention relates to medical virology and can be used in healthcare for the prevention of influenza caused by an epidemic strain of influenza virus. Prevention is carried out by intranasal live influenza vaccine (VHF) from strain A / 17 / California / 04/71 (H3N2).

The vaccine strain of the subtype H3N2 A / 17 / Sydney / 97/76 (H3N2) currently used as part of the trivalent PGW for adults and children [RF Patent No. 2159812, BI 33, 11.27.2000] possesses the necessary genome composition 6: 2, however he lost antigenic relevance. As a result, the strain cannot provide protection during an epidemic caused by a new antigenic species of influenza A virus (H3N2).

The problem to which the invention is directed, is to obtain a vaccine strain of a new antigenic variety based on a cold-adapted attenuation donor A / Leningrad / 134/17/57 (H2N2) using the epidemic virus A / California / 07/04 as a source of surface antigens ( H3N2).

The vaccine strain A / 17 / California / 04/71 (H3N2) was obtained by classical genetic reassortment of the epidemic virus A / California / 07/04 (H3N2) with the cold-adapted strain A / Leningrad / 134/17/57 (H2N2) followed by selection in the presence of the antiserum to the attenuation donor A / Leningrad / 134/17/57 (H2N2).

Attenuation donor A / Leningrad / 134/17/57 (Н2N2) - a cold-adapted temperature-sensitive strain of influenza virus, approved for the production of harmless intranasal vaccines for adults and children [GI Aleksandrova New in the epidemiology and prevention of viral infections. L., 1986. - S. 66-83]. Currently used vaccine strains of live hepatitis B are obtained by reassorting modern epidemic viruses with cold-adapted (HA) donor strains, resulting in the formation of reassortants with a mixed genome. Genes encoding hemagglutinin (HA) and neuraminidase (NA) are inherited from the antigenically relevant epidemic strain, and six genes of internal and non-structural proteins (PB2, PB1, PA, NP, M, NS) from the harmless CA attenuation donor.

Analysis of the genome of the obtained vaccine strain, performed by means of restriction enzyme analysis of DNA copies of RNA segments obtained by polymerase chain reaction (PCR) [Klimov AIJVirol. Method - 1995. - No. 55. - P.445-446] showed that the reassortant A / 17 / California / 04/71 (H3N2) inherited the HA and NA genes from the parental epidemic virus A / California / 07/04 (H3N2), and 6 genes of non-glycosylated proteins from HA of attenuation donor A / Leningrad / 134/17/57 (Н2N2) (genome formula 6: 2). The affiliation of hemagglutinin to the parental epidemic virus A / California / 07/04 (H3N2) was confirmed in the hemagglutination inhibition reaction (RTGA) with 1% suspension of human red blood cells using a set of immune rat antisera. The strain is temperature-sensitive (titer difference at 33 ° C and 39 ° C - 6.0 IgEID ₅₀ / ml) and cold-adapted (titer difference at 33 ° C and 25 ° C - 3.5 IgEID ₅₀ / ml).

Thus, the presented vaccine strain A / 17 / California / 04/71 (H3N2) is characterized by a combination of useful features necessary for the vaccine strain — the antigenic specificity of the hemagglutinin of the epidemic virus A / California / 07/04 (H3N2), the genome structure optimal for reassortant vaccine strains (6: 2), temperature sensitivity, cold adaptation, which correlates with the safety for humans characteristic of an attenuation donor. The morphology of the strain is polymorphic, typical of the influenza virus.

Characterization of the obtained strain.

Infectious activity during reproduction in developing chicken embryos at 33 ° C for 48 hours - 8.0 IgEID 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 passport for the vaccine strain A / 17 / California / 04/71 (H3N2) is attached as an example embodiment of the invention.

The strain is deposited in the collection of the State Institute of Standardization and Control of Medical and Biological Preparations under No. 145.

Strain A / 17 / California / 04/71 (H3N2) isreactogenic with intranasal administration for an adult population, which was tested on volunteers.

Example 1. When vaccinating 48 adults with an intranasally recombinant vaccine strain A / 17 / California / 04/71 (H3N2) with an infectious activity of 8.0 EID ₅₀ / 0.2 ml in a dilution of 1: 2 in a volume of 0.5 ml of strong temperature reactions with a temperature increase over 38.5 ° C, moderate reactions with a short-term temperature increase in the range of 37.6-38.5 ° C and weak temperature reactions (up to 37.5 ° C) were not observed. The reactogenicity index was 0%. Catarrhal phenomena were observed in 2.08% of vaccinated. In a group of 50 people who received a placebo, catarrhal phenomena were observed in 3.9% (Table 1).

Table 1. A drug Number of persons Temperature reactions Catarrhal phenomena 37.0 37.1-37.6 > = 38.6 Ggv 48 0 0 0 1 (2.08%) Placebo 51 0 0 0 2 (3.9%)

Thus, the vaccine strain A / 17 / California / 04/71 (H3N2) satisfies the requirements for vaccine strains of PHA pharmacopeia article FSP 42-0417, which allows the use of the strain for the preparation of the vaccine for adults and children.

Strain passport

1. The name of the strain is A / 17 / California / 04/71 (H3N2)

2. Series - Series 1

3. The method of receipt - reassortment; characteristic of parent viruses:

a) epidemic virus - A / California / 07/04 (H3N2)

b) donor of attenuation A / Leningrad / 134/17/57 (Н2N2)

4. The number of passages - 7 in the process of recombination

5. Characterization of the strain before lyophilization:

a) optimal reproduction conditions - 33 °, 48 hours;

b) hemagglutinating activity 1: 256;

c) infectious activity of 8.0 IgEID ₅₀ / 0.2 ml;

d) sensitivity to inhibitors: inhibitor-resistant;

d) the difference in terms of infectious activity at 33 ° C and 39 ° C - 6.0 IgEID _50/1 ml;

e) the difference in terms of infectious activity at 33 ° C and 25 ° C - 3.5 IgEID _50/1 ml;

g) the structure of the genome of the reassortant:

- genes for the epidemic virus HA, NA

- genes from an attenuation donor - PA, PB1, PB2, NP, M, NS

6. Characterization of the strain after lyophilization:

a) date of lyophilization: 05.16.2005;

b) the volume of material in the ampoule: 1 ml;

c) the number of doses in the ampoule: 2;

d) infectious activity - 7.5 IgEID ₅₀ / 0.2 ml

d) hemagglutinating activity - 1:64

7. Recommended dilution with vaccination 1: 2

8. Antigenic specificity:

a) hemagglutinin - identical to virus A / California / 07/04 (H3N2) according to RTGA with rat antiserum.

b) neuraminidase - identical to virus A / California / 07/04 (H3N2) according to PCR restriction enzyme analysis of DNA copies of genes.

9. Harmlessness for mice with intranasal administration - harmless.

10. Bacteriological control of lyophilized material: date of carrying out - 05/23/2005 - sterile.

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

Claims (1)

The strain of influenza virus A / 17 / California / 04/71 (H3N2), GISK No. 145 (State Institute of Standardization and Control named after L.A. Tarasevich), used to obtain a live influenza intranasal vaccine for adults and children.