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D P Monga

Publications and source records attributed to D P Monga.

At least 19 recordsLinked to original sources
PubMed2002

Comparative analysis of the outer membrane protein profiles of isolates of the Pasteurella multocida (B:2) associated with haemorrhagic septicaemia.

Outer membrane proteins (OMP) of P. multocida (serotype B:2) field isolates (n = 6) and a vaccine strain (P-52) were extracted by a sarkosyl method and characterized using SDS-PAGE and immunoblotting. About 20 polypeptide bands were observed in the profile of the vaccine strain with MW ranging from 16 to 90 kDa and, based on band thickness and intensity of staining, three polypeptides of MW 31, 33 and 37 kDa were considered to be the major OMPs. The profiles of the field isolates showed minor differences when compared with that of the vaccine strain. The OMP of 33 kDa was only expressed by the vaccine strain. Four field isolates expressed an OMP of 39 kDa, which did not appear in the profiles of the remaining two field isolates and the P-52 strain. Similarly, an OMP of 25 kDa was exclusively seen in the profile of a single isolate. By immunoblotting studies, using anti-P. multocida (P-52) whole-cell hyperimmune serum raised in rabbits as well as buffalo immune sera, it became evident that the polypeptide of 37 kDa was the most antigenic OMP in the profiles of all the isolates, including the P-52 strain. Other polypeptides were either weakly antigenic or visible in the profile of only a few of the isolates. The study thus identified the major OMP of P. multocida (B:2) and suggested that this highly antigenic 37 kDa OMP has potential for further protective and immunodiagnostic studies.

Animals↗
PubMed1993

Studies on activation and levels of haemolytic complement of buffalo (Bubalus bubalis). III. C3 haemolytic activity in health and chronic disease.

Estimation of haemolytic complement component C3 activity in serum was done by using buffalo serum functionally depleted of C3, with methylamine. In the one-step alternate pathway (AP) haemolytic assay, C3 activity in the serum was estimated by its capacity to reconstitute the AP haemolytic activity in C3 depleted serum. Levels of haemolytic C3 were determined in the sera of 70 apparently healthy buffaloes and of seven diseased buffaloes of which five were suffering from Johne's disease (JD) and two from JD and tuberculosis (TB). The haemolytic C3 levels in healthy animals varied with age, reaching peak values in the 2.5-3-year-old, declining after 4 years of age. The C3 levels in buffaloes suffering from chronic diseases was significantly higher (P < 0.05) than the levels in healthy buffaloes of the same age group.

Aging↗
PubMed1988

Effect of aflatoxin B1 on the delayed type hypersensitivity and phagocytic activity of reticuloendothelial system in chickens.

Efforts were made to see the effect of feeding aflatoxin B1 at 0.3 ppm level on various aspects of the immune system in chickens. The birds were fed aflatoxin B1 (AFB1) mixed ration from 0 to 6 weeks of age and thereafter normal feed was given up to 12 weeks of age. The delayed type hypersensitivity reaction of these birds was assessed by contact sensitivity to Dinitrofluorobenzene. The dietary AFB1 significantly suppressed the cell mediated immune response at all the three periods tested (30, 45 and 60 days of age). The toxin showed residual effect on immunity as the suppression of cell mediated immunity was maximum three days after the withdrawal of toxin from the feed. The effect of AFB1 on the phagocytic status of reticulo endothelial system (RES) was assessed by colloidal carbon clearance test at various intervals. The residual effect of toxin was observed on RES too as phagocytic index of AFB1 fed birds was significantly lowered up to 45 days of age.

Aflatoxin B1↗
PubMed1987

Studies of the role of B-cells in the resistance of mice to experimental candidiasis.

The role of humoral immunity in experimental candidiasis was studied in B-cell-deficient mice. The B-cell deficiency was produced by administration of anti-mu antibodies to newborn animals. These anti-IgM-treated mice failed to produce antibodies against sheep red blood cells (SRBC), and their lymph nodes and spleens did not form germinal centres. However, their cell-mediated immune responses were normal as they developed delayed hypersensitivity to SRBC and rejected skin allografts like normal animals. These B-cell-deficient animals along with the controls were infected with one LD50 dose of Candida albicans. These animals were observed for mortality, antibody formation, delayed type hypersensitivity (DTH) to Candida antigen and viable count of the organism in different organs. The course of the experimental infection was almost parallel in both the groups. B-cell deficiency did not increase the susceptibility of the animals to experimental candidiasis.

Animals↗
PubMed1987

Studies of experimental candidiasis in T-cell-deficient mice.

The role of cell-mediated immunity (CMI) in the protection against experimental murine candidiasis was studied. CMI-deficient animals prepared by adult thymectomy and treatment with antimouse thymocyte serum along with controls were challenged with one LD50 (6.6 X 10(4)) dose of Candida albicans. The course of infection in these animals was studied by mortality pattern, delayed type hypersensitivity reaction (DTH) to candida antigen, antibody formation, and viable count of organisms in kidney, spleen and liver at different time intervals. The T-cell-deficient animals were found to be highly susceptible to infection with C. albicans. A correlation was observed in the appearance of DTH and protection.

Animals↗
PubMed1983

Studies on experimental aspergillosis in immunodeficient mice.

Mice with either chemically suppressed immune response or with specifically induced T cell or B cell immunodeficiency were challenged with Aspergillus fumigatus spores. Chemical immunosuppressants used were cortisone, cyclophosphamide or silica. T cell deficiency was produced by thymectomy and ALS administration, whereas, B cell deficiency was produced by administration of anti-mouse IgM antibodies in newborn mice. The susceptibility of such animals to A. fumigatus challenge was monitored by mortality pattern and by demonstration of dissemination of fungus in different organs. The administration of cortisone or silica made mice highly susceptible to A. fumigatus infection, whereas, cyclophosphamide initially lowered host's resistance but later had little effect. Mice with B cell deficiency also did not differ significantly from normal animals. Similarly passive transfer of specific antibodies to A. fumigatus did not enhance the protection of the host to experimental aspergillosis. However, the deficiency of T cells and macrophages either alone or in combination made the animals highly susceptible to experimental aspergillosis. The results provide evidence that T cells and macrophages play essential role in immunity to murine aspergillosis. Whereas, B cell deficiency or even passive transfer of specific antibodies to A. fumigatus does not alter much the host's susceptibility to experimental aspergillosis.

Animals↗
PubMed1981

Role of macrophages in resistance of mice to experimental cryptococcosis.

Mice with either a stimulated or depressed reticuloendothelial system were used to study the role of macrophages in resistance to experimental Cryptococcus neoformans infection. Silica, administered intravenously to destroy macrophages, considerably decreased the phagocytic index of the reticuloendothelial system as determined by a carbon clearance test. Silica given 1 day before intravenous challenge with 5 X 10(3) (1 50% lethal dose) of C. neoformans markedly decreased the resistance of mice to cryptococcal infection. Mice given repeated doses of BCG to nonspecifically activate their macrophages could withstand a challenge of 100 50% lethal doses of C. neoformans. These results provide evidence that macrophages play an essential role in natural or nonspecific cell-mediated immunity to murine cryptococcosis.

Animals↗
PubMed1980

A compilation of published reports of mycoses in animals in India.

The available published reports on animal mycoses in India and the fungal agents isolated from animal material are discussed. Among dermatophytes, the occurrence of Trichophyton verrucosum, T. mentagrophytes, T. rubrum, T. equimum, T. violaceum, T. simii, T. tonsurans, T. terrestre, T. ajelloi, Microsporum canis, M. gypseum and M. namum has been reported. Cases of aspergillosis, candidiasis, phycomycosis, rhinosporidiosis, epizootic lymphangitis, mycotic abortions and mycotic mastitis have been recorded in animals in this country. However, there is no report of histoplasmosis, sporotrichosis, blastomycosis and coccidioidomycosis among animals from India.

Abortion, Veterinary↗
PubMed1979

Experimental cryptococcosis in normal and B-cell-deficient mice.

B-cell-deficient mice were prepared by administration of rabbit anti-mouse-mu antiserum to newborn animals within 12 h of birth onwards. Such immunodeficient animals, along with the normal controls, were infected intravenously with Cryptococcus neoformans. There was no difference in the mortality pattern, viable count of cryptococci in different organs, delayed-type hypersensitivity reaction, and antigen level in the sera of control and B-cell-deficient animals. Antibodies were absent in B-cell-deficient animals but were present in low titers in control animals. It is concluded that antibodies are not involved in protection of mice infected with C. neoformans.

Animals↗