C. W. Potter

Clinical studies of monovalent inactivated whole virus and subunit A/USSR/77 (H1N1) vaccine: serological responses and clinical reactions

The clinical acceptability and antibody responses to graded doses of whole virus, aqueous surface antigen and adsorbed surface antigen influenza A/USSR/92/77 (H1N1) virus vaccines were assessed in 1335 healthy volunteers in a double-blind, multi-centre study conducted in the U.K. in February and March 1978. Before vaccination the presence of haemagglutination-inhibiting (HI) and neuraminidase-inhibiting (NI) serum anti-bodies to the vaccine virus was infrequent and in low titres in volunteers aged ≤ 25 years but was more frequent in older persons. In volunteers aged ≤ 25 years, who were sero-negative for HI antibody before vaccination, the HI antibody responses following one dose of vaccine were generally of low frequency and titre for all doses and types of vaccine. Nevertheless, whole virus or subunit vaccines with high antigenic content (≥ 47 μg haemagglutinin (HA) per dose) induced HI antibody responses in at least 60% of recipients. Following two doses of whole virus, aqueous or adsorbed surface antigen vaccine containing at least 9 μg HA per dose, serum HI titres of ≥ 40 were detected in 69–100% of recipients. In volunteers aged ≥ 26 years, who received a single dose of any of the test vaccines containing at least 3 μg HA, the HI antibody responses were frequent and post vaccine titres of ≥ 40 were detected in 80% of vaccinees. A ‘shallow’ dose response effect over a wide range of antigen concentrations of whole virus (5–94 μg HA per dose) or subunit vaccines was noted for each age group. Both the geometric mean HI antibody titres and proportion of vaccinees developing HI titres ≥ 40 were similar for each age group when comparable doses of vaccine were given by the subcutaneous and intradermal routes. A preliminary study of the NI antibody responses to vaccination indicated that all the whole virus and subunit vaccines stimulated serum NI antibodies in a proportion of recipients. All vaccines were clinically well tolerated.

Immunopotentiation of local and systemic humoral immune responses by ISCOMs, liposomes and FCA: role in protection against influenza A in mice

The immunogenicity and protective efficacy of an influenza A subunit vaccine preparation administered to mice in an aqueous form, or presented as immunostimulatory complexes (ISCOMs), liposomes or with Freunds complete adjuvant (FCA), were assessed in comparative studies with live infectious virus. Both intranasal and parenteral routes of administration were assessed. An enzyme-linked immunosorbent assay (ELISA) was used to measure nasal wash and serum antibody responses in groups of unprimed mice, while protection was determined by the recovery of homologous influenza virus from mouse nasal washes and lung homogenates following challenge infection by the intranasal route. The results showed that parenteral administration of the influenza antigen preparations induced variable levels of both local and systemic antibodies at weeks 3, 7 and 22 postimmunization. Although the overall greatest levels of antibody and protection were elicited in mice following live virus infection, formulation of influenza surface haemagglutinin (HA) and neuraminidase (NA) proteins into ISCOMs elicited high and persistent antibody responses and provided relatively good protection of the upper and lower respiratory tracts of these animals. The results also show a relatively poor effect of the subunit antigen preparations in promoting humoral immune responses and protection irrespective of the nature of their presentation, when given by the intranasal route.

The specificity of the anti-haemagglutinin antibody response induced in man by inactivated influenza vaccines and by natural infection.

The anti-haemagglutinin antibody response in adult human volunteers to inactivated whole virus or tween ether split influenza A/Victoria/75 (H3N2) and A/Scotland/74 (H3N2) virus vaccines was investigated using antibody absorption and single-radial-haemolysis (SRH) techniques. The concentrations of haemagglutinin (HA), nucleoprotein (NP) and matrix (M) antigens measured by single radial diffusion (SRD) and rocket immunoelectrophoresis were similar for both the whole virus and split vaccines. Whole virus and split vaccines induced crossreactive (CR) antibody in 87% of vaccinees. Strain specific (SS) antibody to A/Hong Kong/1/68 of the homologous virus was induced less frequently than CR antibody. Higher anti-haemagglutinin antibody titres were detected in persons receiving the split virus vaccines than in those receiving the whole virus vaccines. No antibody to the type-specific matrix protein was detectable, but 33% of volunteers developed an antibody rise to type-specific nucleoprotein antigen. The specificity of the anti-haemagglutinin antibody response in human adults to natural infection with A/Port Chalmers/73 (H3N2) virus was similar to that induced by inactivated vaccines in that a high proportion of subjects developed CR anti-haemagglutinin antibody, which reacted with A/Hong Kong/68 virus and the homologous A/Port Chalmers/73 virus, and SS antibody for A/Hong Kong/68 virus but SS antibody for A/Port Chalmers/73 virus was infrequently stimulated by natural infection.

Immunity to influenza in ferrets

The response of ferrets to inoculation with tri-(n-butyl) phosphate split influenza A/Aichi/68 virus vaccine is reported. Normal ferrets did not produce detectable levels of serum HI antibody following inoculation with a single dose of either 640 or 6400 CCA of virus vaccine but produced low titres of antibody following two inoculations of 6400 CCA of virus. This antibody was insufficient to protect the animals against challenge infection with influenza virus A/Hong Kong/68. Ferrets which had been primed by previous infection with heterotypic influenza virus A/PR/8/34, however, responded to immunization with a single dose of 640 CCA of TNBP-split A/Aichi/68 virus by the production of low titres of serum HI antibody. Following immunization these animals were found to be susceptible to challenge infection. The difference in immunogenicity between the TNBP-split vaccine and similar concentrations of whole virus vaccine given to primed ferrets is discussed.

Efficacy of topical acyclovir cream in first and recurrent episodes of genital herpes

Fifty-three patients with first episodes and 60 patients with prior culture proven recurrent genital herpes were enrolled in a single centre, double-blind, placebo-controlled trial of 5% acyclovir in an aqueous cream base versus matching placebo. For first episodes treated with topical acyclovir the median duration of pain (4 vs. 8 days, P less than 0.05), time to healing of all lesions (8 vs. 14 days, P less than 0.001), duration of viral shedding (4 vs. 11 days, P = 0.001) and duration of new lesion formation (0 vs. 2.5 days, P less than 0.001) were reduced compared with placebo recipients. In patients with recurrent episodes who completed the study topical acyclovir significantly reduced the median duration of all symptoms (3 vs. 6 days, P less than 0.001), the time to healing of all lesions (4 vs. 6 days, P less than 0.01), and the formation of new lesions (5 vs. 29%, P less than 0.01) compared with the controls. Greater clinical benefits were demonstrated in females than in males, particularly for first episodes, but the number of males was small. Topical acyclovir cream is well tolerated and an effective treatment for first and recurrent episodes of genital herpes.

The IgA and subclass IgG responses and protection in mice immunised with influenza antigens administered as ISCOMS, with FCA, ALH or as infectious virus

SummaryComparative studies on the local IgA, and circulating IgG subclass antibody responses of mice to A/Sichuan/2/87 (H3N2) influenza virus surface antigens administered with different carrier or delivery systems by the parenteral route, were carried out. The results obtained were compared with the responses observed following live influenza virus infection, and the protection afforded to these animals by these various preparations determined.Infection with live virus elicited early and high levels of protection against homologous virus challenge and this correlated with both local IgA and circulating IgG2a antibody levels. When incorporated into immunostimulating complexes (ISCOMS), A/Sichuan surface antigens promoted high levels of local IgA and circulating IgG1 antibody, and achieved a more rapid and more solid immunity against homologous virus challenge infection, than that elicited by the same surface antigens administered alone or together with Freunds complete adjuvant or alhydrogel.

Depressed spontaneous natural killing and interferon augmentation in patients with malignant lymphoma.

A substantial proportion (44%) of peripheral blood lymphocyte samples from 41 patients with malignant lymphoma have been shown to have depressed or undetectable levels of natural cytotoxicity against the leukaemic cell line K562 in a 4-hr [51Cr]-release assay. No correlation was found between low levels of natural killer (NK) cell activity and either the age of the patients, total or differential white blood counts, or the type or stage of disease. Furthermore, pre-treatment of lymphocytes with human lymphoblastoid (Namalva) interferon failed to enhance NK levels in 5/11 patients with Hodgkins disease and 5/8 patients with non-Hodgkins lymphoma, and was in contrast to the response of control peripheral blood lymphocytes assayed under the same test conditions. The lack of responsiveness to interferon of peripheral blood NK cells from lymphoma patients was not wholly associated with those patients shown to have low levels of spontaneous NK activity.

Immune response of human volunteers and animals to vaccination with egg-grown influenza A (H1N1) virus is influenced by three amino acid substitutions in the haemagglutinin molecule

Inactivated subunit vaccines were prepared from high-growth reassortants derived from two separate egg isolates from a single clinical specimen of influenza A (H1N1) virus. One of these reassortants, NIB-14, was antigenically indistinguishable from isolates made in tissue culture, while the other, NIB-17, was antigenically different and typical of egg isolates. The viruses differed by three amino acid residues in the haemagglutinin (HA) molecule and the anti-HA serological response induced was studied in animal models and human volunteers. In the volunteer groups both vaccines induced very high levels of circulating haemagglutination inhibition antibodies but with different serological specificities. Both NIB-14 and NIB-17 vaccines induced high levels of cross-reactive antibodies capable of reacting with both strains, but only NIB-14 vaccine induced significant levels of strain-specific antibodies capable of reacting exclusively with the homologous strain. Antisera containing only cross-reactive antibodies proved as capable of virus neutralization as antisera containing high levels of strain-specific antibodies. We extended the argument that epidemic strains are antigenically more closely related to tissue culture isolates and established that viruses which differ by only single amino acids at critical points in the HA structure can induce a significantly different immune response when used as inactivated vaccines.

Chromosome studies in eleven colorectal tumors

Cytogenetic analysis is presented on seven freshly derived colorectal tumors and four established cell lines (SW 742, SW 480, SW 948, and HT 29). No chromosome change was common to all tumors, although previous nonrandom findings were confirmed. Single chromosome abnormalities were identified in two cases, 47,XX,+i(7p) and 46,XX,-17,+der(17),t(17;?)(p;?), and their relevance to tumor origin and development is discussed. The association of i(8q) with tumors of the rectosigmoidal region is confirmed, and it is suggested that other rearrangements involving loss of 8p may have the same association. Abnormalities resulting in loss of 20p and duplication of 20q, not previously reported as a nonrandom change, were seen in seven out of 11 cases.

The immune response of hamsters to purified haemagglutinins and whole influenza virus vaccines following live influenza virus infection

The ability of several, live type A influenza viruses to enhance the serum haemagglutination-inhibiting (HI) antibody response of hamsters to subsequent immunization with inactivated, heterotypic influenza virus vaccines was examined. Live influenza viruses were found to vary in their priming ability for a given vaccine, and a given virus was not able to prime for all inactivated vaccines to an equal extent. Common determinants in the haemagglutinin antigens of the priming virus and the vaccine virus were suggested as responsible for the enhancement of the antibody response to some of the vaccines, but for other pairs of viruses the haemagglutinin antigens were distinct. Thus, enhancement in these instances cannot be due to cross-reacting haemagglutinins. Pre-infection of hamsters by several influenza type A viruses was employed in an attempt to enhance the serum HI antibody response to purified, haemagglutinin antigens prepared from A/PR/8/34 and the MRC-2 recombinant strain of A/England/42/72 viruses. Although prior infection enhanced the antibody response to whole virus, this was not demonstrable for the purified haemagglutinin components of the virus. The possible reasons for this are discussed.