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1.
Am J Trop Med Hyg ; 44(3): 314-22, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2035753

RESUMO

Two strains of mice, A. SW (H-2s) and A.CA (H-2f), were immunized with live trypomastigotes or epimastigotes of the Tulahuen strain of Trypanosoma cruzi or with their sonicates. By immunowestern blotting, sera from A.SW mice, but not from A.CA, recognized, in an immunodominant fashion, a 45 kDal polypeptide (Tc45) present in both epimastigotes and trypomastigotes. Since A.SW and A.CA strains are congenic for the major histocompatibility H-2 complex, recognition of Tc45 seems to be controlled by this genetic region or by gene(s) located in its immediate vicinity. Subcellular fractionation revealed that Tc45 is mainly present at the cytoplasmic compartment.


Assuntos
Anticorpos Antiprotozoários/biossíntese , Antígenos de Protozoários/imunologia , Trypanosoma cruzi/imunologia , Animais , Antígenos de Protozoários/análise , Antígenos de Protozoários/genética , Western Blotting , Eletroforese em Gel de Poliacrilamida , Feminino , Epitopos Imunodominantes , Camundongos , Camundongos Endogâmicos A , Sonicação
2.
Braz J Med Biol Res ; 23(8): 685-95, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2129269

RESUMO

1. Resistance to acute Trypanosoma cruzi infection in mice is a polygenic character with a major factor linked to the murine major histocompatibility system (H-2). We found that F1 hybrids A.CA(H-2f)/B10.Br(H-2k) between two susceptible strains are strongly resistant. 2. Resistant B10(H-2b) and A.SW(H-2s) animals survived 60 or more days after an intraperitoneal injection of 10(4) Tulahuén strain blood trypomastigotes. The specific antibody response of these individuals increased continuously up to 100 days or more. Parasitemia reached a peak at day 8 in all strains. Thereafter, the number of blood parasites in resistant animals showed an irregular but persistent decrease. 3. Susceptible congenic B10.Br and A.CA animals showed lower levels of specific anti-T. cruzi antibodies and an increase in parasitemia until death. B10.Br mice died 14 to 20 days after infection. A.CA animals were extremely susceptible, showing a sharp and sustained increase in parasitemia starting on day 12, followed by death no later than day 15 post-inoculation. 4. We found a significant correlation between IgG levels present in serum of resistant mice from 20 days on and protection against acute death. Whole immune anti-T. cruzi serum or its purified IgG class fraction neutralized T. cruzi inocula in vitro as shown by a significantly increased survival of recipient susceptible A.CA mice. 5. This IgG protective effect is independent of the protective effect mediated by the terminal activation of the complement cascade, since the parasites were inoculated with heat-inactivated immune sera and both recipient (A.CA) and donor (A.SW) strains lack C5.


Assuntos
Anticorpos Antiprotozoários/análise , Doença de Chagas/imunologia , Imunoglobulina G/imunologia , Trypanosoma cruzi/imunologia , Animais , Doença de Chagas/genética , Suscetibilidade a Doenças , Feminino , Genes MHC da Classe II , Ligação Genética , Soros Imunes/imunologia , Camundongos , Camundongos Endogâmicos
6.
Immunology ; 36(4): 775-80, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-108207

RESUMO

Glutaraldehyde (GA)-treated sheep red blood cells (SRBC) or H-2-allogeneic spleen cells (SC), induced immunological memory with absent or markedly reduced primary antibody production. In contrast, a normal secondary response was obtained when GA-SRBC or GA-SC were given to mice primed with the corresponding untreated antigens. The secondary response of mice primed and boosted with GA-treated cells was relatively high with GA-SRBC, and negative or very low with GA-SC. Morphological studies of the fate of intraperitoneally injected cells showed that endocytosed GA-SRBC persisted much longer in peritoneal macrophages than untreated SRBC. Simultaneous challenge of mice with untreated and GA-treated SRBC revealed that phagocytosis and digestion of both types of cells in the same macrophage proceeded independently of each other. The primary response of mice receiving both SRBC and GA-SRBC was entirely similar to the response when SRBC alone was given.


Assuntos
Aldeídos/farmacologia , Formação de Anticorpos/efeitos dos fármacos , Glutaral/farmacologia , Memória Imunológica/efeitos dos fármacos , Animais , Eritrócitos/efeitos dos fármacos , Eritrócitos/imunologia , Antígenos H-2/imunologia , Transfusão de Linfócitos , Linfócitos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos , Baço/citologia , Transplante Homólogo
7.
Exp Clin Immunogenet ; 2(4): 198-205, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3917149

RESUMO

A system of two public serum antigens, alpha and delta, whose distribution in inbred strains of mice is different from that of all serum antigens known, is described. Their distribution in the H-2 congenic and in the recombinant inbred HTG strain indicates that they are determined by a gene(s) tightly linked to H-2. Backcross tests confirmed this; only 1.1-cM recombinants were found. The gene(s) is located at the D side of H-2. The immunogenicity of the serum specificities in A/Sn animals, but not in other strains, is sex-limited. These serum antigens are also present in most tissues and, in high amounts, in red blood cells. No sex differences in the absorbing capacity of tissues or the agglutinability of red blood cells were found. All these findings indicate that alpha and delta antigens belong to a new H-2-linked system. A relationship with the recently found new class I genes is suggested.


Assuntos
Genes MHC Classe I , Antígenos H-2/genética , Camundongos Endogâmicos/imunologia , Animais , Feminino , Antígenos H-2/imunologia , Masculino , Camundongos , Camundongos Endogâmicos/genética , Especificidade de Órgãos , Recombinação Genética , Fatores Sexuais
8.
Proc Natl Acad Sci U S A ; 75(2): 963-5, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-273258

RESUMO

Two electrophoretic variants of murine complement component 3 (C3) were detected by using high-voltage electrophoresis of fresh mouse serum in agarose gels. Most of the inbred strains tested were homozygous for the S allele (for the slow-migrating variant); only four out of 46 strains had the alternative F allele (fast variant). Pen-bred Swiss-Webster animals belonged to one of three phenotypes--S, F, or SF--and the genes responsible for this variation segregated in a strictly Mendelian manner. In three such crosses, with 5* offspring, C3 segregated with H-2 in 46 instances, corresponding to a recombination frequency of approximately equal to 0.12.


Assuntos
Complemento C3/genética , Genes , Variação Genética , Histocompatibilidade , Camundongos/genética , Animais , Complemento C3/biossíntese , Eletroforese , Ligação Genética , Camundongos Endogâmicos
18.
Braz. j. med. biol. res ; 23(8): 685-95, 1990. tab, ilus
Artigo em Inglês | LILACS | ID: lil-92277

RESUMO

Resistance to acute Trypanosoma cruzi infection in mice is a polygenic character with a major factor linked to the murine major histocompatibility system (H-2). We found that F1 hybrids A. CA(H-cf)I B10.Br(H-2k) between two susceptible strains are strongly resistant. 2. Resistant B10 B10(H-2b) and A. SW(H-2s) animals survived 60 or more days after an intraperitoneal injection of 10**4 Tulahuén strain blood trypomastigortes. The specific antibody response of these individuals increased continuously up to 10 up to 100 days or more. Parasitemiareached a peak at day 8 in all strains. Thereafter, the number of blood in resistant animals showed an irregular but persisten decrease. 3. Susceptible congenic B10.Br and A.CA animals showed lower levels of specific anti-T. cruzi antibodies and an increase in parasitemia until death. B10.Br mice died 14 to 20 days after infection. A.CA animals were extremely susceptible, showing a sharp and sustained increase in parasitemia starting on day 12, followed by death no later than day 15 post-inoculation. 4. We found a significant correlation between IgG levels present in serum of resistant mice from 20 days on and protection against acute death. Whole immune anti-T. cruzi serum or its purified IgG class fraction neutralized T. cruzi inocula in vitro as shown by a significantly increased ssurvival of recipient susceptible A.CA mice. 5. This IgG protective effect is independent of the protective effect mediated by the terminal activation of the complement cascade, since the parasites were inoculated with heat-inactivated immune sera and both recipient (A.CA) and donor (A.SW) strains lackC5


Assuntos
Camundongos , Animais , Feminino , Anticorpos Antiprotozoários/análise , Doença de Chagas/imunologia , Imunoglobulina G/imunologia , Trypanosoma cruzi/imunologia , Doença de Chagas/genética , Suscetibilidade a Doenças , Genes MHC da Classe II , Ligação Genética , Soros Imunes , Camundongos Endogâmicos
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