Immunogenicity of Ribosomal Preparations from Yeast Cells of Histoplasma capsulatum

Immunization with ribosomal preparations from Haemophilus influenzae type b elicited protective immunity in mice. Ribosomes from disrupted cells where isolated by differential centrifugation using sodium dodecyl sulfate. The washed ribosomes contained 25% protein and 75% ribonucleic acid and sedimented as a single peak on sucrose density gradient analysis with a sedimentation coefficient of 67S, using Escherichia coli ribosomes as a 70S marker. Immunodiffusion tests with antipolyribose phosphate serum showed that the ribosomes were free from capsular material. Mice immunized subcutaneously with ribosomes, with or without adjuvant, were challenged intraperitoneally with 100 to 1,000 mean lethal doses of H. influenzae type b suspended in gastric mucin. Significant protection was induced by ribosomes and was compared to that obtained after sublethal infection with live cells. The protection was greatly enhanced after incorporation of ribosomes into adjuvants. Maximum protection (90 to 95%) was observed at 1 to 2 weeks after immunization. Ribosomes from a nonencapsulated strain of H. influenzae were as immunogenic as those from the encapsulated strain, demonstrating that the capsular material is not responsible for immunogenicity of Haemophilus ribosomes.

Section: Discussionsupporting

confidence: 78%

Immunoprotective activity of ribosomes from Haemophilus influenzae

Lynn¹,

Tewari²,

Solotorovsky³

1977

“…Previous work from our laboratory demonstrated a high degree of protection in mice immunized with ribosomes or ribosomal protein from H. capsulatum; this protection was com-parable to that obtained by immunization with live cells (6,25). This report presents the results of a study that was designed to compare the roles of immune serum and lymphoid cells in adoptive transfer of immunity from mice immunized with ribosomes or with live yeast cells of H. capsulatum.…”

mentioning

confidence: 59%

“…Preparation of ribosomes. Ribosomes were prepared according to a modified procedure of Youmans and Youmans (27) described previously (6). Briefly, the washed yeast cell suspension of H. capsulatum was disrupted in a Braun (MSK) homogenizer (B. Braun Co., Melsungen, Germany).…”

Section: Organism H Capsulatum Brown Type (G-217b)mentioning

confidence: 99%

Adoptive transfer of immunity from mice immunized with ribosomes or live yeast cells of Histoplasma capsulatum

Tewari¹,

Sharma²,

Solotorovsky³

et al. 1977

This investigation was designed to compare the role of lymphoid cells and immune serum in protective immunity induced by immunization with ribosomes or live yeast cells of Histoplasma capsulatum. Spleen cells, peritoneal cells, and serum from CH mice immunized with Histoplasma ribosomes or live cells were transferred intravenously to separate groups of syngeneic recipients. All recipients along with a set of immunized and control mice were challenged intravenously with 4 x 106 yeast cells of H. capsulatum, and protection was assessed. Immunization with ribosomes or live cells provided 90 to 100% protection. Mice receiving filtered spleen cells or peritoneal cells from donors immunized with live cells showed 90 to 100% protection; 80 to 90% protection was observed for mice receiving cells from ribosome-immunized donors. In contrast, no evidence of protection was seen in mice receiving serum from either live-cellor ribosome-immunized mice. Peritoneal cells were far more efficient than spleen cells in adoptive transfer of immunity. The adoptive immunity in recipients persisted for at least 3 weeks after transfer, the longest period tested in the present study. These results indicate that the immunity elicited by immunization with Histoplasma ribosomes or live cells is mediated by a cellular mechanism.

“…This DTH response was negative in all groups receiving intravenous treatments when tested 21 and 80 days after the last immunization injection. The 7 12 11 8 a The immunization schedule was the same as that described in Table 1, footnote a. FKP, Formalin-killed promastigotes.…”

Section: Resultsmentioning

confidence: 99%

“…Ribosome-derived and ribonucleic-acid-rich extracts of some bacteria, fungi (7,12,17,18,28) and, more recently, of the kinetoplastid protozoon Trypanosoma cruzi (16) have been shown to confer a degree of protective immunity against infection in experimental animals. Studies aimed at further antigenic analysis of ribosomal and other subcellular fractions of L. donovani are merited to differentiate common and strain-specific antigens.…”

Section: Discussionmentioning

confidence: 99%

Immunogenicity of soluble and particulate antigens from Leishmania donovani: effect of glucan as an adjuvant

Cook¹,

Holbrook²

1983

The protective efficacy of glucan as an adjuvant with killed promastigotes of Leishmania donovani was compared with that of soluble or particulate fractions of the parasite. When these vaccine preparations were injected either intravenously or subcutaneously in CF-1 mice, glucan potentiated resistance against L. donovani infections as reflected by significant reductions in hepatic amastigote counts relative to infected control mice. The leishmanial antigens alone afforded no protection. Serum direct agglutination titers to leishmanial antigens were highest in all groups given the vaccine intravenously, whereas the delayed-type hypersensitivity response to the antigen was positive only in groups immunized subcutaneously with glucan as an adjuvant. Some index of protection and immune response against visceral infection with the parasite was seen in groups vaccinated with glucan and soluble antigens. However, the protection afforded by glucan and particulate antigens of L. donovani more closely paralleled the resistance of mice treated with glucan and unfractionated killed promastigotes. Further antigenic analysis of particulate fractions of L. donovani may optimize effective immunization when used with appropriate adjuvants, e.g., glucan.