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Biomedical subjects

R Ganguly

Publications and source records attributed to R Ganguly.

At least 91 records · Page 5Linked to original sources
PubMed1976

Suppression of cell-mediated immunity after infection with attenuated rubella virus.

The effects of attenuated rubella virus infection upon cell-mediated immunity of human volunteers were studied. The volunteers received the vaccine either by nose drops or by the subcutaneous route. Changes in cell-mediated immunity in terms of delayed cutaneous sensitivity to recall antigens, phytohemagglutination stimulation, and spontaneous migration inhibitory factor-like activity were studied at various time periods after infection. Spontaneous migration inhibitory factor-like activity was studied on supernatants of the lymphocytes obtained from the volunteers and incubated for 72 h in the absence of any antigens. A significant proportion of the volunteers showed suppression of one or more parameters of cell-medicated immunity tested by week 2 of infection compared to the control; however, there was no correlation between suppression of the various parameters studied. No difference was noticed in the incidence of cell-mediated immunity suppression between nose drops and subcutaneous route groups.

Adult↗
PubMed1975

Effect of freezing and storing on the biological properties of macrophages.

Storage of intact macrophages would be a useful procedure for laboratories studying the biological functions of these cells. Oil-induced guinea pig peritoneal cells were harvested and frozen at an ultra-low temperature using a cryoprotective media. Studies of the biological properties of the frozen cells upon thawing indicated that the cells retained viability for a fairly long period of time, were metabolically active and comparable to normal cells in morphology. Indications of activation were obtained in enhanced phagocytic activity and significant decrease in migration of the stored cells.

Animals↗
PubMed1975

An indirect radioimmunoassay for mouse casein using 125I-labeled antigen.

A new indirect radioimmunoassay was developed for detection of casein in mouse milk and in mammary tissue extract. Preincubation of rabbit gamma globulin to mouse milk casein (Ca2+-rennin precipitate) with unlabeled casein, milk, extracts of mammary tissues of late pregnancy and lactation, virtually blocked subsequent binding of 125I-labeled mouse milk casein to the antibody. Preincubation with mouse serum, bovine serum albumin, rennin, extracts of liver or immature mammary tissue had little effect on [125I]casein binding to the antibody. The inability of [125I]casein to bind to the antibody after preincubation with protein samples, which are likely to contain casein, is indicative of a specific antigen-antibody reaction. The assay is capable of detecting 0.2 mug casein, 1 mug milk proteins and 10 mug lactating mammary tissue extract. The application of the assay was also demonstrated using organ culture of the entire mammary gland. The glands treated with the lactogenic hormones, insulin + prolactin + cortisol, showed a saturation level of antibody-antigen reaction, indicating hormonal induction of casein; whereas, no reaction was observed with the non-treated gland.

Animals↗
PubMed1975

Murine mammary gland RNA directed synthesis of casein in a heterologous cell-free protein synthesis system.

A cell-free protein synthesis system derived from Ehrlich ascites tumor cell ribosomes (S30) plus rabbit reticulocyte tRNA was developed and the activity of the system was dependent on rabbit reticulocyte ribosomal salt (0.5 M KC1) wash factors, The exogenous mRNAs from BALB/c mouse liver and the mammary gland were translated with a high efficiency in this heterologous cell-free system. Furthermore, the RNA from the lactating mammary gland faithfully directed the synthesis of casein. The presence of mouse casein in the reaction product was identified by radioimmunoprecipitation with mouse casein antiserum, co-electrophoresis of the reaction product and mouse casein the urea-polyacrylamide gel and by electrophoresis in sodium dodecyl sulfate (SDS) polyacrylamide gel. The major portion of the lactating mammary gland RNA directed synthesis of the milk protein in the cell-free system appeared to be analogous to alphas casein,

Animals↗
PubMed1975

Techniques for eliciting mucosal immune response.

Development of techniques for eliciting an immune response on mucosal surfaces is a relatively new area of clinical research. With the recognition of the existence of secretory immunity, independent of the systemic system, there was renewed interest in re-examining the conventional approach for optimal immunization techniques. A large body of data indicate that the majority of the secretory immunoglobulins and antibody produced to antigenic stimulation of mucosal surfaces is locally produced. Thus, antibody to C. albicans in the cervical or vaginal mucus has been shown to be of local origin and it predominantly belongs to the secretory IgA immunoglobulin class. The mechanism of antigen processing by the secretory surface leading to antibody formation remains a mystery, but it might be determined by the selective localization of antigens in the reticuloendothelial cells of the lamina propria, bronchi or small intestine. Usually application of antigen topically to the mucosal surface elicits local antibody formation to a greater extent than does parenteral immunization. On the other hand, a more pronounced systemic immune response is seen when the antigen is administered systemically. However, a number of other factors determine the quality and quantity of the immune response, e.g., the physical state of the antigen, live vs killed vaccine, dose, adjuvant, previous exposure to similar or cross-reacting antigens, and site of application of the antigen. These factors are discussed in the review. Recent observations suggest that cell mediated immunity is a component of the secretory immune system, and like the humoral mechanism, also may be partially compartmentalized.

Animals↗
PubMed1975

Duration of circulating and secretory antibody and cell-mediated immunity following immunization.

An important consideration in evaluating vaccines is the duration of immunity. The only really important measure of this immunity is the protection against infections and/or illness at various time intervals, following natural or artificial challenge. There are few data of this sort, more commonly immunity is estimated by measuring serum antibody, in many instances an erroneous measure. Serum antibody levels to respiratory viruses fall only slightly 6 months following infection or immunization. It is difficult to assess the duration of antibody for much longer than this, because of problems with intercurrent infection. With respiratory bacterial infections, e.g. pneumococcal pneumonia, parenterally-induced immunity probably lasts for only several months. Secretory antibody induced by inactivated viral vaccines, seems to persist for about a year, after having reached a peak level at about 4-6 weeks following immunization. Work with the live attenuated polio virus vaccine indicates longer lasting immunity, with detectable antibody persisting for up to 34 months. Restimulation with the inactivated polio virus vaccine produced no evidence of a secondary response (memory). Following booster immunization with influenza very little evidence of memory is seen. Cell-mediated immunity (CMI): in guinea pigs BCG sensitization can be demonstrated for at least 2-9 months. In humans, intracutaneous BCG immunization leads to positive tuberculin reaction in 6-10 weeks, and skin sensitivity lasts an average of about 4 years. There is contradicting data as to the duration of protection against infection following BCG immunization. Local and systemic CMI have been shown to exist independently of each other in experimental animals and man.

Animals↗
PubMed1975

Antibody response in the intestinal secretions of volunteers immunized with various cholera vaccines.

The efficacy of various cholera vaccines in eliciting an intestinal antibody response was assessed in human volunteers who received oral live, oral killed, or parenteral cholera vaccines, or placebo. The intestinal immune response in terms of antibacterial and antitoxin antibodies was determined 2 and 4 weeks after immunization. By means of the mouse peritoneum opsonization assay and the infant mouse protection test, antibacterial activity could be detected in the intestinal secretions of volunteers who had been immunized either orally or by the parenteral route. Significant protective activity and duration of immunity were observed with the oral killed vaccine. The bacteriological data indicated the absence of significant intestinal colonization of the live attenuated strain after oral administration, and probably explains the observed lack of effectiveness of the oral vaccine compared with that of the killed vaccine. The predominant immunoglobulin class of intestinal antibody was found to be IgA. None of the vaccines used in the study elicited significant antitoxin activity in the intestinal secretions, as determined by the skin permeability neutralization test.

Adult↗
PubMed1974

Immunosuppression during influenza virus infection.

The effects of a live attenuated influenza vaccine and subsequent challenge with virulent influenza virus on the delayed hypersensitivity skin test, and the in vitro response of lymphocytes were evaluated. Volunteers were skin tested before and after administration of vaccine or placebo and challenge with PPD (a purified protein derivative of Mycobacterium tuberculosis), candida, mumps, and trichophytin, and their lymphocytes were tested for [(3)H]thymidine uptake in response to phytohemagglutin. Of eight volunteers who showed evidence of viral replication after administration of the attenuated vaccine, four had a significant diminution in their skin test response, whereas 8 of 13 volunteers infected with virulent influenza virus showed a diminution. Of the 21 volunteers who were infected with either attenuated or virulent influenza virus, 12 showed suppression of their phytohemagglutin response. None of the volunteers who were given placebo vaccine, or who showed no evidence for viral replication after immunization or challenge, had a suppression of their skin test or phytohemagglutin responses. Although most of the infected volunteers demonstrated suppression of their T-cell function, there was no evidence of a similar suppression of B-cell function.

Journal Article↗
PubMed1973

Rubella immunization of volunteers via the respiratory tract.

The efficacy of various routes of administration of the live attenuated rubella virus vaccine was evaluated by using 46 seronegative volunteers who were divided into 4 vaccine groups: subcutaneous, nosedrops, spray into posterior oropharynx and nose using large particle aerosol, and inhalation of small particle aerosol through the mouth. Seroconversion was observed in all of the vaccinees regardless of route of immunization. Nasal secretion antibody 6 weeks after immunization was highest in the volunteers who received the vaccine by nose drops (all members of this group had demonstrable nasal secretion antibody after immunization). Only half of the volunteers in the subcutaneous group developed demonstrable nasal secretion antibody. This suggests that nasal secretion antibody was best stimulated when vaccine was given directly into the nose. Volunteers were challenged with the vaccine intranasally at 6 to 8 weeks. None of the volunteers exhibited clinical symptoms or fourfold or greater serum antibody rises after challenge, but fourfold or greater nasal secretion antibody rises were observed in three volunteers in the subcutaneous vaccine group and two in the aerosol group, suggesting that those volunteers had not been protected against challenge. Rubella virus was isolated 8 to 12 days after challenge in two persons in the subcutaneous group and three in the aerosol vaccine group, but none in the nose drops or spray groups. Thus, protection after nasal challenge appeared to be best in those groups which also had the best nasal secretion antibody response after immunization. However, protection did not seem to be correlated with either nasal secretion or serum antibody levels.

Administration, Intranasal↗
PubMed1972

Oral immunization of mice with killed Salmonella typhimurium vaccine.

A study was undertaken to assess the efficacy of oral, parenteral, and intraperitoneal immunization methods of administering killed Salmonella typhimurium vaccine to mice and to evaluate the effectiveness of single and multiple doses of the vaccine containing varied numbers of the killed bacteria. A further objective of this study was to evaluate the effect of adding substances to the vaccine to which have been ascribed "adjuvant" properties. The protection was estimated by isolation of bacteria from the spleen and feces after oral challenge of the mice with live S. typhimurium. The results showed that one or more doses of 10(10) organisms given orally led to significant protection. This rate of protection increased proportionately with the number of doses up to 10 doses, which offered 100% protection. Streptomycin, when added to multiple doses of 10(9) or more organisms given orally, increased the degree of protection, but beryllium sulfate and pertussis vaccine did not. Although multiple doses afforded similar systemic protection by all three routes of immunization, oral immunization yielded significantly greater local protection than that observed after subcutaneous or intraperitoneal immunization.

Adjuvants, Immunologic↗