Cytokine profile after rubella vaccine inoculation: evidence of the immunosuppressive effect of vaccination

BACKGROUND AND AIM: Immunization with live virus vaccines may cause an immunosuppression with lymphopaenia, impaired cytokine production and defective lymphocyte response to mitogenes. These abnormalities were described in subjects vaccinated against measles. This study was performed to analyse the host immune response related to immunosuppression in subjects vaccinated with live attenuated rubella vaccine. METHODS: Eighteen schoolgirls, aged 11-13 years, were vaccinated with live attenuated rubella vaccine Rudivax. Before immunization, and 7 and 30 days after, peripheral blood was collected. Cellular fractions were subjected to flow cytometric analysis, and the lymphocyte response to phytohaemagglutinin was investigated. Plasma samples were analysed for cytokines (interleukin (IL)-4, IL-10, tumour necrosis factor-alpha, and interferon-gamma) by enzyme-linked immunosorbent assay techniques. RESULTS: On day 7 after vaccination, the number of each lymphocyte subset was decreased; however, only for CD3 and CD4 lymphocytes has a significant reduction been shown. On the contrary, tumour necrosis factor-alpha and IL-10 levels markedly increased and amounted to its maximum on day 30. Simultaneously, a significant reduction in plasma interferon-gamma and a profound decrease of the lymphocyte response to phytohaemagglutinin were shown. The changes were accompanied with marked elevation of plasma IL-4. CONCLUSIONS: Our data indicate that the vaccination with live attenuated rubella vaccine results in moderate but sustained immune disturbance. The signs of immunosuppression, including defective lymphocyte response to mitogene and impaired cytokine production, may persist for at least 1 month after vaccination.     

Evaluation of live trivalent vaccine of measles AIK-C strain, mumps Hoshino strain and rubella Takahashi strain, by virus-specific interferon-gamma production and antibody response

A trivalent measles-mumps-rubella live virus vaccine, containing measles AIK-C strain, mumps Hoshino strain, and rubella Takahashi strain, was evaluated in 229 children, aged 1 to 5 years. The vaccine induced a high seroconversion rate: 221 (98.7%) out of 224 subjects initially seronegative for measles virus, 167 (93.3%) out of 179 initially seronegative for mumps virus, and 212 (99.1%) out of 214 initially seronegative for rubella virus. It also induced a sufficient cellular immunity against each of the three viruses in over 90% of the subjects, as judged by virus-specific interferon-gamma (IFN-gamma) production. Virus-specific IFN-gamma production was observed 10 days after vaccination by stimulation with measles virus and rubella virus and 14 days after vaccination by stimulation with mumps virus. Mumps-virus-specific IFN-gamma production was observed in 7 out of 12 recipients without seroconversion for mumps virus. And measles-virus-specific IFN-gamma production was demonstrated in one out of three recipients without seroconversion for measles virus. A significant correlation was observed between the serum antibody and IFN-gamma production six weeks after vaccination for measles virus (r = 0.201, P less than 0.01) and for mumps virus (r = 0.174, P less than 0.05) but not for rubella virus (r = -0.045, P less than 0.05). The incidence of febrile reactions of greater than or equal to 37.5 C was quite low, 14.4%, and that of greater than or equal to 39 C occurred in only 1.3% of the recipients. These results suggested that the trivalent vaccine induced sufficient humoral and cellular immunity and yet resulted in no more untoward reaction than observed from the measles vaccine alone.     

A differential effect of IgM and IgG antibodies on the blastogenic response of lymphocytes to rubella virus

Peripheral blood lymphocytes of rabbits immunized with live rubella vaccine respond to rubella virus antigens in tissue culture with increased DNA synthesis as measured by incorporation of ³H-thymidine. This reaction can be inhibited by rubella antibody. A dose dependent effect was observed when antibodies in whole serum were mixed with virus prior to addition to lymphocyte cultures. When antisera were fractionated and their individual immunoglobulins tested, a paradoxical effect was obtained. Immune IgG although it was highly effective in neutralizing the virus was incapable of inhibiting the lymphocyte response and at times caused an increased response. In contrast, immune IgM which was less efficient in neutralizing virus caused significant suppression of the blastogenic reaction. By themselves these results might have signified that IgG and IgM antibodies have different specificities or different binding properties with respect to viral surface antigens. However, immune complexes consisting of virus and IgM reduced response of both rubella immune and normal rabbit lymphocytes to PHA. This nonspecific inhibitory action required a specific step of antigen and IgM antibody interaction and normal IgM-virus mixtures or mixtures of anti-rubella IgM and poliovirus or influenza virus did not suppress lymphocyte response to PHA. Anti-rubella IgG complexed with rubella virus did not suppress the PHA response. The IgG function was apparently limited to neutralization of the infectivity of rubella virus whereas the major role of IgM was manifested through its suppressive effect on lymphocyte reactions.     

Interferon-induced 2-5A synthetase activity in human peripheral blood mononuclear cells after immunization with influenza virus and rubella virus vaccines.

The interferon-induced enzyme 2-5A synthetase can be a sensitive indicator of activation of the human interferon system during viral infection or interferon therapy. To determine the response of the human interferon system to viral antigens, the level of 2-5A synthetase activity was monitored in peripheral blood mononuclear cells of healthy adults before and after immunization with influenza or rubella virus vaccine. The influenza virus-vaccinated individuals demonstrated increases in enzyme activity on days 1 and 11 in vivo, whereas those vaccinated with rubella virus vaccine showed an increase only on day 11. The difference in the day 1 in vivo 2-5A synthetase response in the two vaccinated groups could be demonstrated by in vitro incubations of peripheral blood mononuclear cells isolated approximately 90 days postvaccination with the two vaccines. The day 11 increase of enzyme activity in the rubella virus group showed a positive correlation with an increase in serum antibody titer, suggesting activation of the interferon system during antibody production in vivo after human exposure to virus antigens. The demonstration of increased 2-5A synthetase activity at specific times postimmunization in this investigation indicates that the interferon system is involved in the human in vivo response to virus vaccination.     

Delayed-type hypersensitivity and in vitro lymphocyte response in guinea pigs immunized with a live varicella vaccine

The relation of delayed type hypersensitivity (DTH) assessed by the Varicella-Zoster virus (VZV) skin test and lymphocyte transformation (LTF) with VZV antigen was investigated in guinea pigs immunized with live varicella vaccine virus, or heat-inactivated vaccine virus. Guinea pigs immunized with live varicella vaccine virus showed positive DTH and LTF responses to viral antigen as well as a neutralizing (NT) antibody response, while those immunized with heat-inactivated vaccine virus showed only an NT antibody response of the same degree as that to live vaccine virus. These results show the reliability of the skin test in assessing cell-mediated immunity (CMI) to VZV and the advantage of the live varicella vaccine over the inactivated one in immunizing guinea pigs.     

Effect of HLA on the cellular immune response to varicella-zoster virus

The effect of HLA on varicella-zoster virus (VZV)-specific lymphocyte transformation (LTF) was studied in 100 normal immune adults and 64 children who were immunized with live attenuated varicella vaccine. In the normal adults, a statistically significant association was observed between low responsiveness and the presence of A2 (p less than 0.025), and also between high responsiveness and the presence of Aw24 (p less than 0.05). A similar but clearer association, i.e. low responsiveness with A2 (p less than 0.005) and high responsiveness with Aw24 (p less than 0.025), was observed in the vaccinated children. In these children, Aw31 was also found to be related to low responsiveness (p less than 0.05). These results suggest that the VZV-specific cellular immune response is in some way influenced by HLA.     

Cell-mediated immune response to mumps virus infection in man.

The antibody and cell-mediated immune response to mumps virus infection was studied in groups of subjects after natrually acquired mumps virus infection, after parenteral immunization with live attenuated mumps vaccine, and in a population of mumps seronegative subjects. The technique of neutralization of tissue culture infectivity was utilized to study mumps specific antibody. The cell-mediated immunity (CMI) was detected by specific immune release (SIR) of radioactivity by purified lymphocytes after they were reacted with radioactive chromium (51Cr) labeled human conjunctival cell cultures chronically infected with mumps virus. No SIR activity was observed in lymphocytes obtained from cord blood and young individuals seronegative for antibody to mumps virus. Detectable SIR activity was observed in a few older seronegative subjects; however, immunization with mumps vaccine in such antibody negative subjects failed to result in the development of any antibody response in the serum. High SIR activity was observed in the lymphocytes of naturally infected and vaccinated subjects. Although all naturally infected or immunized subjects had varying levels of mumps specific antibody activity in the serum, no correlation existed between the levels of antibody and SIR activity. These observations suggest the development of mumps specific in vitro correlates of CMI after naturally acquired or vaccine-induced mumps virus infection.     

Studies on live rubella vaccine. V. Quantitative aspects of interference between rubella, measles and mumps viruses in their trivalent vaccine

Rubella vaccine combined with measles and mumps vaccines was administered in a single injection to children of 1 to 5 years of age. All three vaccines were serologically effective, and the clinical reactions caused by measles vaccine were considerably alleviated, when 6 x 10(3) PFU of rubella and 10(4) TCD50 per dose of mumps vaccines were combined with 5 x 10(4) TCD50 of measles vaccine. When a larger amount of mumps vaccine (3 x 10(5) TCD50/dose) was used, it caused interference with the rubella and measles viruses, i.e., the antibody response to rubella virus became poor and the incidence of clinical reactions to measles virus decreased. On the other hand, when 5 x 10(5) TCD50/dose of measles vaccine was combined with 10(4) TCD50/dose of mumps vaccine, the clinical reactions to measles virus were decreased but were almost the same as those induced by this vaccine alone.     

Antibody response in school children to live rubella vaccine (Cendehill strain)

The efficacy of an attenuated rubella virus vaccine, Cendevax, was tested on 65 school children. Forty-nine of them (75%) had pre-existing antibodies and in these there was no increase in the HAI antibody titres after administration of the vaccine. Sixteen children (25%) had no demonstrable rubella HAI antibody prior to vaccination. From the latter group, postvaccination serum samples were available from only 11, and 10 of these seronegative children showed seroconversion after vaccination. The geometric mean HAI titre was 1:180. Seven of the 10 postvaccination serum samples had complement-fixing antibodies and specific IgM antibodies were detected by the immunofluorescence test in 8. No correlation was observed between the CF and the IgM antibodies.     

Persistence of naturally acquired cell-mediated immunity to rubella virus during the first trimester of pregnancy

We studied the persistence of naturally acquired cell-mediated immunity to rubella during early pregnancy. We compared lymphocyte transformation responses to phytohemagglutinin and rubella virus in 35 naturally immune women aged 17-37 years, in the first trimester of pregnancy, with 49 naturally immune age-matched nonpregnant controls. A significant lower lymphocyte transformation response to phytohemagglutinin was observed during the first trimester of pregnancy (P = 0.008), but lymphocyte transformation responses to rubella virus were not significantly different (P = 0.901). These data indicate that, in naturally immune women, cell-mediated immunity to rubella virus is not significantly altered by the physiological changes in early pregnancy.     

Antibody responses following rubella immunization analyzed by HLA and ABO types

HLA typing was performed on 232 rubella seronegative (HAI antibody titer <8) children immunized with RA 27/3 vaccine. High convalescentphase geometric mean antibody titers were noted in children one to five years of age, in girls one to 12 years of age, in subjects with AB blood type and in vaccinees with HLA types B14 and BW22. Of nine children with rubella titers512, 44 percent had HLA type A28; in contrast, only eight percent of the total group had A28 HLA type. HLA-A2 was present in four, and HLA types B12 and BW17 were present in three of the six children in whom seroconversion did not occur. Fifteen of 37 sibling pairs had identical antibody responses; in contrast, only 18 percent of randomly paired children had titers identical to each other. Vaccine-related symptomatology could not be associated with any HLA type. The results of this study suggest that infection with and antibody response to RA 27/3 rubella vaccine is influenced by genetic factors, which include cellular membrane determinants.     

Rubella in Russia: variability of the infectious agent during the period of vaccine prophylaxis

AIM: To assess influence of vaccination against rubella on the genetic diversity of rubella virus. MATERIALS AND METHODS: Vaccine strains of rubella virus Wistar 27/3 and Orlov-B as well as sera from patients with rubella obtained in Perm region during 1999 - 2005 period and standard serologic, molecular, epidemiologic and statistical methods were used. The study was performed according to the WHO recommendations on the genotyping of wild rubellavirus strains. RESULTS: Strains of rubella virus isolated in Perm region, vaccine strain Orlov-B (Saint Petersburg), and 4 Russian strains isolated in 1967-1997 before vaccine introduction belong to the same genetic group with high degree of homology - genetic divergence do not exceed 0 - 1%. This group was identified as genotype 2c which, according to WHO's data, circulates only in Russia. Periods of epidemic peaks of rubella incidence and its falls as well as selective immunization of girls and women of childbearing age did not influence on the genetic stability of the virus (divergence did not exceed 0.6 - 2.0%). On the contrary, mass immunization of children aged 1 - 2 years during 4 years resulted in statistically significant changes of rubella virus subtype inside the genotype 2c. CONCLUSION: Ten-year experience of rubella vaccination in Perm region demonstrates necessity of inclusion of monitoring for rubella virus variability in the system of epidemiological surveillance and control for rubella infection during period of its prevention by vaccine.     

The shapin of psychiatry by science and humanism. II. An emerging synthesis of science and humanism.

Serological surveys of rubella antibody were carried out using the hemagglutination-inhibition test, with a view to studying the distribution of seroimmune individuals according to age and intermingling with other populations. Specimens were collected from different age groups including infants, children and adults, among the inhabitants of Montreal from 1963 to 1968. From the results obtained it was possible to establish the pattern of rubella antibody development in this urban community. Surveys were also conducted among the inhabitants of Les Iles de la Madeleine, a Canadian island in the Gulf of St. Lawrence, and among the population of Easter Island, an isolated island in the South Pacific remote from any large land mass.It was seen that, among the inhabitants of Montreal, presumably maternally acquired rubella antibody was present in 95% or more of the infants, the same percentage of seroimmune individuals as was found among the adult women 25 to 30 years of age. Passively acquired rubella antibodies decreased rapidly, attaining their lowest levels among children 1 to 2 years old. Rubella infection occurred in young children and its incidence rose steeply from school age to adolescence, leaving 7 to 9% of the adults without antibody. The highest geometric mean antibody titres were found among children 4 to 10 years of age.The same pattern of rubella antibody development was found among the population of Les Iles de la Madeleine, except that in adults the percentages of seropositives reached practically 100%. Antibody titres decreased with advancing age and became lower than those found among children.Detection of rubella antibody in serum samples derived from the inhabitants of Easter Island indicated that this population had experienced rubella infection not long before the Canadian Medical Expedition of 1964-1965. This status is determined from the high proportion of seroimmune individuals in each age group and the uniformly high antibody titre.Island populations appear to represent the ideal subjects for estimating the duration of the immunity conferred by any attenuated rubella vaccine that will eventually be licensed.     

Guide to the management of rubella problems.

Despite the availability of rubella vaccine the incidence of the congenital rubella syndrome has been increasing in certain regions of Canada. Perhaps this is not surprising in view of the known irregular cyclic activity of rubella virus in a community and the fact that the percentage of seropositive women of childbearing age has not changed appreciable since the vaccine was introduced. Clearly vaccine is not being administered to sufficient numbers of women at risk. Until a much higher percentage of women of childbearing age possess rubella antibody, the costly problem of congenital rubella syndrome is likely to be with us. Common rubella problems relate to four categories: the exposed pregnant woman, laboratory diagnosis, the infant with suspected congenital rubella and the vaccine. One of the most common questions about the vaccine is the following: Can recently vaccinated individuals disseminate vaccine and infect seronegative contact? The answer is No.     

Clinical trial with inactivated hepatitis A vaccine and recommendations for its use.

OBJECTIVE--To compare the reactogenicity and immunogenicity of an inactivated hepatitis A vaccine in two different immunisation schedules. DESIGN--Randomised trial. SETTING--One London teaching hospital. SUBJECTS--104 healthy adult volunteers (71 men, 33 women aged 19-60). INTERVENTIONS--Hepatitis A vaccine to group 1 (54 volunteers) at 0, 1, and 2 months and to group 2 (50) at 0, 1, and 6 months. MAIN OUTCOME MEASURES--Symptoms at and after each dose; liver function, hepatitis A virus specific serum immune response; and responses in saliva and parotid fluid in immunised volunteers and subjects with natural immunity. RESULTS--The vaccine was well tolerated; 97% (96/99) and 100% of those immunised developed serum antibody after one and two doses of vaccine respectively. Geometric mean titres increased progressively after each dose and were significantly higher in men but not women in group 2 after the third dose (ratio between geometric mean titres 0.265, 95% confidence interval 0.18 to 0.39; p less than 0.001). At one year this group-sex interaction was absent; geometric mean titres for both sexes were significantly higher in group 2 (ratio 0.330, 0.227 to 0.478; p less than 0.0001). Antibody responses were not significantly different between the groups at two years. Compared with naturally infected subjects immunised volunteers developed poor or undetectable virus specific IgG and IgA responses in saliva and parotid fluid. CONCLUSIONS--The vaccine was safe and highly immunogenic, and the differences in the immune responses in saliva and parotid fluid are unlikely to affect its efficacy.     

风疹减毒活疫苗主种子批毒种(松叶株)的安全性和免疫原性检测

评价兰州生物制品研究所用风疹病毒松叶株主种子批毒种制备的冻干风疹减毒活疫苗的安全性和免疫原性。采用自身对照、开放性的免疫原性临床观察试验,对100名8～10月龄筛选后符合条件的健康易感儿童,皮下接种1剂风疹减毒活疫苗,观察其免疫后的局部和全身反应并采集每个受试者免前和免后35d的血清标本,检测风疹HI抗体,计算阳转率和几何平均滴度。试验中所有受试者在系统观察期内均未观察到注射部位局部的不良反应;总的发热率为5%,且均为轻度发热;有1例在观察期内出现腹泻和咳嗽并持续5d,发生率为1%,属中度全身反应;血清风疹病毒抗体(HI)阳转率为100%,GMT为1:638.7±1.7。该疫苗与国内、外其它种类的风疹疫苗一样具有良好的安全性和免疫原性。     

Live Attenuated Rubella Vaccine (Cendehill Strain) in School Children

The purpose of this study was to further determine the efficacy and safety in school children of the Cendehill strain of live attenuated rubella vaccine. Parental permission was requested for 255 children in Grades I, II and VI, attending two adjacent schools, to have blood taken for rubella hemagglutination-inhibition studies at the beginning and end of the study, and for each child seronegative on initial testing to participate as a vaccinee or a control. Vaccinees received either 0.5 ml. (full recommended dose) or 0.25 ml. of rubella virus vaccine, live attenuated, Cendehill strain (Smith Kline & French).Eighty-one per cent of the parents consented to have their child take part. Seventy-nine per cent of Grade I and II pupils and 41% of Grade VI pupils were found to be susceptible to rubella at the time of the initial test (HI titres [unk] 8). Eighty children received rubella vaccine and 98.7% showed at least a four-fold rise in antibody titre. One child who received 0.25 ml. showed only a two-fold rise. Clinical reactions to the vaccine were absent or minimal. Thirty-eight controls remained serologically negative during the study.The good response to half-doses of Cendehill vaccine is not significant because there were >3000 TCID₅₀ in a full dose (three times the dose recommended). This information was unknown by the investigators until the termination of the study.     

Rubella-neutralizing and haemagglutinin-inhibiting antibodies in children of different ages

Rubella neutralization and haemagglutinin-inhibition tests were used to determine the incidence of rubella antibodies in the sera of 235 children and adolescents aged 1 month to 20 years. The tests showed good agreement in the detection of rubella antibodies resulting from acute infection. Maternal antibodies became undetectable within six months after birth. The proportion of children possessing rubella antibodies was found to be about 23% by the age of 5 years, rising sharply to 80% in the 6–12 years age group and 83% in the 13–20 years age group. Results indicate that the incidence of rubella infection may be higher in females than in males. The correlation between statements concerning a past history of rubella and immune status was poor, particularly in the older age groups. Any policy for vaccination against rubella must take into account the difficulties of identifying nonimmune persons in a large population.     

A TritonX-100-split Virion Influenza Vaccine is Safe and Fulfills the Committee for Proprietary Medicinal Products (CPMP) Recommendations for the European Community for Immunogenicity,in Children,Adults and the Elderly

Influenza epidemics are an important cause of morbidity and mortality throughout the world. Current recommendations from Health Authorities emphasize annual immunization of people who are particularly at risk from an influenza virus infection; however, vaccination of working adults and of school children also has been shown to provide public health benefits. To give it a more advantageous reactogenicity profile than the diethylether-split influenza vaccines available previously, a split virion influenza vaccine has been produced with TritonX-100. In a series of clinical trials, Aventis Pasteur (formerly, Pasteur Mérieux Connaught) tested both the safety and immunogenicity of this TritonX-100-split virion influenza vaccine in 566 subjects (42 children, 296 adults, and 228 elderly adults) during three influenza seasons (1991, 1993, and 1995). The TritonX-100-split virion vaccine was well tolerated: no serious adverse events were recorded during the 21 days following immunization. Among the local reactions observed, mild pain, redness, or induration at the injection site were the most frequently reported. Fever (38·0 to 38·5°C) was noted in five adults or elderly subjects (1%), and in two children (5%). Immunogenicity was determined by measuring serum haemagglutinin antibody titres specific to each vaccine virus strain. In each of the three vaccination campaigns, the TritonX-100-split virion influenza vaccine fulfilled the Notes for Guidance on Harmonization of Requirements for Influenza Vaccines outlined by the Committee for Proprietary Medicinal Products (CPMP) of the European Community for an influenza virus vaccine (i.e., seroprotection, seroconversion, or increase of geometric mean titre) in all age groups.     

Sero-Molecular Epidemiology of Japanese Encephalitis in Zhejiang,an Eastern Province of China

BackgroundSporadic Japanese encephalitis (JE) cases still have been reported in Zhejiang Province in recent years, and concerns about vaccine cross-protection and population-level immunity have been raised off and on within the public health sphere. Genotype I (GI) has replaced GIII as the dominant genotype in Asian countries during the past few decades, which caused considerable concerns about the potential change of epidemiology characteristics and the vaccine effectiveness. The aim of this study was to investigate the prevalence of JE neutralizing antibody and its waning antibody trend after live attenuated JE vaccine immunization. Additionally, this study analyzed the molecular characteristics of the E gene of Zhejiang Japanese encephalitis virus (JEV) strains, and established genetic relationships with other JEV strains.Conclusion/SignificancesJE neutralizing antibody positive rates increase in age ≥10 years old population, likely reflecting natural infection or natural boosting of immunity through exposure to wild virus. JE seropositivity rates were quite low in <35 years old age groups in Zhejiang Province. Waning of neutralizing antibody after live attenuated vaccine immunization was observed, but the clinical significance should be further investigated. Both the peripheral antibody response and genetic characterization indicate that current live attenuated JE vaccine conferred equal neutralizing potency against GI or GIII of wild strains. GI has replaced GIII as the dominant genotype in Zhejiang in the past few decades. Although the chance of exposure to wild JE virus has reduced, the virus still circulates in nature; therefore, it is necessary to implement immunization program for children continually and to conduct surveillance activity periodically.