In vivo production of human hybridoma antibody to the Haemophilus influenzae B capsule in athymic nude mice.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to R A Insel.
Explore the source record for details and available documents.
An old concept--passively immunizing a fetus by actively immunizing (vaccinating) its mother--is reevaluated in light of 50 years of data. The history and data reviewed here suggest that this concept is one whose time has come for active modern research and clinical use. In Third World countries, this concept already has provided significant reduction in morbidity and mortality from neonatal infections such as tetanus. Some other neonatal and infant infections--heretofore life-threatening--may now have a practical method for prevention. These include group B beta-streptococcal sepsis and Hemophilus influenzae meningitis.
The simultaneous serum and mucosal antibody response to parenteral vaccination with the Haemophilus influenzae type b (Hib) polysaccharide capsule (PRP) was evaluated in a group of 10 children and nine adults. All subjects responded to parenteral vaccination with an increase in serum anticapsular antibody. The children's preimmunization anti-PRP antibody level (mean = 0.04 microgram/ml) and 3 wk postimmunization level (mean = 19.3 micrograms/ml) were lower than the adults' (preimmunization mean = 1.5 microgram/ml; postimmunization mean = 81.2 micrograms/ml). Eight of 10 children and seven of nine adults also developed a rise in antibody in nasal secretions. The children's mean nasal preimmunization level was 0.74 microgram/mg IgA and mean postimmunization level was 5.0 micrograms/mg IgA. The adults' mean nasal preimmunization level was 0.98 microgram/mg IgA and mean postimmunization level was 3.0 micrograms/mg IgA. Salivary antibody responses generally followed the pattern of nasal antibody responses. These data suggest that parenteral administration with the Hib capsular polysaccharide can produce a mucosal antibody response. Furthermore, although serum antibody responses to PRP vaccination are greater in adults than in children, mucosal antibody responses are comparable.
Monoclonal antibodies are identical antibodies with the same binding specificity that can be generated in unlimited amounts by construction of continuous cultures of single antibody-secreting cells. These cell lines are produced by cell fusion of lymphocytes of an animal that produces desired antibody to cells of a myeloma tumor cell line, which confers, on the antibody-producing hybrid cell, immortality and the ability to grow as a tumor in animals. Monoclonal antibodies can be produced to complex, impure antigens. The antibodies are replacing conventional, polyclonal antisera in immunologic assays and are being widely applied to the study of the pathogenesis and to the diagnosis and treatment of childhood diseases.
The prevalence of natural mucosal antibody to the capsular polysaccharide (polyribosylribitolphosphate [PRP]) of Haemophilus influenzae type b in adults at multiple secretory sites and the relationship between natural serum and mucosal antibodies with respect to their amount and fine binding specificity were examined. All of 16 lactating women had antibody to PRP in serum and mammary samples; 11 of 14 studied had nasal antibody and 12 of 14 had salivary antibody. The amount of serum antibody to PRP in an individual positively correlated with the amount of mucosal antibody at each of the three secretory sites examined, and the antibody amount between certain secretions were also positively correlated. Antibody to PRP that is cross-reactive with Escherichia coli K100 or Streptococcus pneumoniae type 6 capsular polysaccharides was detected in the secretions of seven and one subjects, respectively, but the amount was not correlated with serum cross-reactive antibody.
Monoclonal antibodies to Haemophilus influenzae type b were produced by fusing splenic lymphocytes from immunized C57BL/6 mice with the mouse myeloma line P3-X63-Ag8.653. The antibody produced by one hybridoma (5M1H9) bound the capsular polysaccharide, as determined by a radiolabeled antigen-binding assay. The antibody was of the IgM class and was bactericidal in vitro with complement. The protective and therapeutic capacity of antibody 5M1H9 was examined in the infant rat model of H. influenzae type b disease. Antibody (0.1 ml), either undiluted or diluted 1:2, 1:10, or 1:100, administered 4 hr before intraperitoneal injection of 10(4)-10(5) H. influenzae type b organisms protected 100%, 90%,. 55% and 10% of the animals, respectively. To determine the efficacy of antibody 5M1H9 in treating established infection, antibody was given at 24-hr intervals after intraperitoneal injection of bacteria. Delayed administration of antibody 5M1H9 was effective in reducing both the level and incidence of bacteremia.
Type-specific antigen was purified from the supernatant of type III group B streptococcal cultures, tyrosylated, and bound to microtiter wells for an enzyme-linked immunosorbent assay. The immunological specificity of the antigen and the assay was shown by (i) reaction only with homologous unabsorbed rabbit sera and (ii) inhibition after incubation of human serum with homologous but not heterologous purified antigen. The assay was quantitated by relating optical density readings to absolute amounts of human immunoglobulin G bound to the microtiter wells.
Postimmunization human B lymphocytes and mouse myeloma cells were fused to produce interspecies hybridomas secreting human antibody of predefined specificity with an initial frequency comparable to intraspecies fusion. After 13 mo in culture, one clone continued to secrete high titers of human IgG antitetanus toxin antibody. This antibody binds to the B fragment of tetanus toxin and protects mice against tetanus. The demonstration of in vivo protection with a human monoclonal antibody is an important first step towards the ultimate goal of human administration of monoclonal antibodies for the prevention and therapy of human infections.
Escherichia coli K100 is known to induce antibodies cross-reactive with the capsular polysaccharide (CP) of Haemophilus influenzae b (Hib); the cross-immunogenicity is found consistently in a number of mammalian species including man. We have studied the reciprocal cross-immunogenicity of Hib or its purified CP in man. Of 25 adults and 13 children responding to systemic immunization with Hib CP, only four and four, respectively, made K100 CP cross-reactive antibody, determined by radioantigen-binding inhibition. The detection of preimmunization cross-reactive antibody was not statistically predictive of induction of postimmunization cross-reactive antibody. Cross-reactive antibody was detected in only one of 11 children making an anticapsular response to Hib systemic infection and two of four children responding to asymptomatic nasopharyngeal colonization. In contrast, cross-reactivity was detected in the naturally occurring anti-Hib-CP antibody of 27 of 42 children. Thus, humans responding to Hib or its CP often do not make antibody to the K100-cross-reactive determinant(s), implying that the cross-reactive natural antibodies frequently seen in children must have a stimulus other than Hib.
Complexes containing proteins, capsular polysaccharide (polyribosylribitolphosphate [PRP]), and lipopolysaccharide (LPS) had been isolated from the supernatants of cultures of Haemophilus influenzae type b and were found to elicit rabbit antibodies to PRP much more effectively than did purified PRP vaccine. Similar complexes have now been prepared, in which the LPS content and endotoxic activity are greatly reduced. One such preparation, called polysaccharide-protein complex (PC), elicited antibodies to PRP in a "boostable" pattern in weanling rabbits and antibodies to the somatic components of H. influenzae type b, primarily LPS. PC greatly exceeded PRP in the in vitro stimulation of [3H]thymidine incorporation by mononuclear leukocytes from human peripheral blood; the response occurred in T cells rather than in B cells. Lymphocyte stimulation by conventionally purified PRP appeared to be due to a small residuum of material that resembled PC.
A polysaccharide-protein complex prepared from Haemophilus influenzae type b strain Eagan was used as test antigen in an enzyme-linked immunosorbent assay for human serum antibodies. With washing buffer that did not contain detergent, the assay detected antibody to lipopolysaccharide (LPS) and to non-LPS somatic antigens as well as to polyribosylribitolphosphate (PRP. With buffer that did contain detergent, antibodies to LPS were not detected, whereas detection of antibodies to the non-LPS somatic components and to PRP wa unimpeded. Similarly, purified LPS could be used as test antigen with the former buffer only. IgG, IgA, and IgM antibodies to non-LPS somatic antigens were prevalent in healthy adults and children, and levels increased in 14 of 15 patients recovering from meningitis due to H. influenzae type b; IgG was the predominant class. Antibodies to LPS were prevalent but at lower concentrations, and IgM was the predominant class; levels increased in 12 of the 15 patients.
Polysaccharide-protein complex prepared from Haemophilus influenzae type b strain Eagan was evaluated for toxicity and immunogenicity in adult volunteers given intramuscular injection. Most subjects had moderate local inflammation that was maximal the day after vaccination. No lot of vaccine significantly exceeded a saline placebo in production of systemic symptoms. Neither the local nor the systemic reactions of individual subjects appeared to be related to prevaccination serum antibody titers. Serum antibody responses to the capsular polysaccharide (polyribosylribitolphosphate [PRP]) component were detected in approximately 80% of the subjects. The PRP content of the vaccine antigens varied, and the rate and extent of responses were as expected for an equivalent dose of purified PRP vaccine. Antibody responses were not enhanced by aluminum phosphate. There was no booster response to a second injection given after six months. Responses to the residual lipopolysaccharide component occurred in 80% of the subjects, primarily in the IgG class. Responses to the nonlipopolysaccharide somatic components were detected less frequently.
A woman with rheumatoid arthritis and ampicillin-resistant Haemophilus influenzae type b (Hib) pneumonia complicated by bacteremia and empyema is reported. Initial therapy with cefamandole failed to eliminate bacteria from the pleural space and did not substantially affect the clinical course. However, cultures became negative and fever resolved when therapy was changed to chloramphenicol. Ampicillin-resistant Hib pneumonia in adults is an increasing problem and may be a difficult diagnosis to establish initially. Counterimmunoelectrophoresis may be useful in adults with pneumonia. If Hib antigen is detected, or if H influenzae is suspected on the basis of Gram stains and cultures, chloramphenicol should be given until the isolate is shown to be sensitive to ampicillin.
The possibility that mucosal antibody is produced as a host response to Haemophilus influenzae type b (Hib) infection was examined in this study. 17 of 18 prospectively evaluated children ranging in age from 2 mo to 7 yr developed a detectable level of anticapsular antibody in their nasopharyngeal secretions after systemic Hib infection. The mean concentration of nasal anti-capsular antibody of the 18 children was 554 ng/mg IgA (SD = 35-8,863) during the acute phase of illness and declined to 224 ng/mg IgA (SD = 19-2,688) in convalescence. Some children had mucosal antibody detectable at least 10 mo after infection. The mucosal antibody levels were not affected by the length of illness before diagnosis, type of disease, age of the patient, sex, or presence of detectable capsular antigen or viable bacteria in the nasopharynx. The mucosal antibody was predominantly of the IgA class and occurred independent of the serum antibody. Six of the children aged less than 1 yr who did not produce and/or sustain a serum antibody level correlated with protection demonstrated a persistent mucosal antibody response. These findings suggest that the mucosal immune system may have the ability to respond at an earlier age than the serum immune system and lead us to postulate that protective secretory antibodies to prevent systemic Hib disease may be inducible in young infants in spite of the poor serum antibody response occurring at this age.
Breast milk has a high concentration of secretory immunoglobulin and potentially could serve as a source of passive antibody protection of infants against systemic invasion by Haemophilus influenzae type b. Specific antibody to the capsular polysaccharide of this organism was detected in the colostrum and all subsequent milk samples in 11 of 12 women with a radioactive antigen binding assay. The geometric mean concentrations of antibody were 1.99 microgram/ml in colostrum and 0.18 microgram/ml in breast milk at six weeks and after four and one-half to six months of lactation. Antibody levels in colostrum correlated positively with those in subsequent milk samples; levels after six weeks of lactation correlated highly with those present after four and one-half to six months of lactation. IgA was the predominant immunoglobulin class of anticapsular antibody in the colostrum and milk samples as detected by an enzyme-linked immunosorbent assay.
Lipopolysaccharide from strains of Haemophilus influenzae was extracted and isolated by the hot phenol-water procedure. The preparations were relatively insoluble in water but could be solubilized with surface-active agents. The preparations contained carbohydrate (30%), fatty acid (29%), and phosphate (4.7%); protein content was less than 1%. Thin-layer chromatography, gas-liquid chromatography, and colorimetric assays detected glucose, galactose, glucosamine, heptose, and a 2-keto-3-deoxy-octonate-like molecule (less than 1%). Neither methylpentose nor dideoxyhexose was detected. The lipid portion was composed of fatty acids common to lipopolysaccharide of Salmonella. The preparations provoked positive dermal Shwartzman reactions and biphasic febrile responses in rabbits, responses typical of endotoxic activity. The 50% lethal dose for mice was decreased from 16.5 microgram/g to 0.015 microgram/g by concomitant administration of actinomycin D. The preparations were shown to be polyclonal activators of bone marrow-derived (B) cells. Limulus lysate gelation was seen with 8.0 ng of lipopolysaccharide. Preliminary hemagglutination data suggested at least three different antigenic factors associated with the lipopolysaccharide of H. influenzae type b. The H. influenzae lipopolysaccharide appeared biologically similar to that of enterobacteria but chemically different.
Explore the source record for details and available documents.
Human B lymphocytes obtained from tonsils do not proliferate when stimulated with pokeweed mitogen. A soluble factor produced from T cells cultured with pokeweed mitogen stimulates B cells to synthesize DNA and differentiate into immunoglobulin producing cells. This PWM produced supernatant induced a PFC response to SRBC. The T cell supernatant activity is produced within 12 hr of stimulation in the presence of serum and without a requirement for T cell division. Optimal stimulation of B cells occurred at 7 to 9 days of culture. This helper factor activity eluted postalbumin from a column of Sephadex G-200. Insolubilized pokeweed mitogen was not mitogenic for B cells. The continuous presence of the lectin in culture was not required for B cell proliferation or for immunoglobulin synthesis.