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1.
Hum Immunol ; 5(2): 91-105, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7141899

RESUMO

A pilot study is reported of HLA-A, B, and C antigens in 141 East African Blacks comprising patients with Burkitt's lymphoma or nasopharyngeal carcinoma, either with active disease or in long-term remission, together with comparable controls. This study forms part of a wider program investigating host factors in these diseases. A protocol was selected for optimal testing of cells processed and cryopreserved between 1972 and 1976, largely under field conditions, which employed a two-color fluorochromasia typing procedure. Antigen distribution and computed haplotype frequencies in the total unrelated population are given. New findings include an approximately equal frequency of Aw23 and Aw24, a high (18%) incidence of Bw21, and the gametic associations of Aw36 with Bw44, and Aw30 with Bw45. Of the major group of B15-related antigens reported earlier. SV is the most common, and there are strong linkages of SV with Cw2 and Bu with Cw3. The possible presence of further variants at the A- and B-loci is reported. The proportion of B-locus antigen "blanks" in this study is 5.9%. Relationships have been sought between the HLA antigens and diseases studied: the antigen A29, possibly in linkage with Bw42, shows a correlation with disease susceptibility, and associations are suggested between Bw44 (in possible combination with Aw36) and resistance to both BL and NPC, and between Bw45 and long-term remission in NPC.


Assuntos
Linfoma de Burkitt/genética , Carcinoma/genética , Antígenos HLA/genética , Neoplasias Nasofaríngeas/genética , Adolescente , Adulto , África Oriental , População Negra , Criança , Pré-Escolar , Feminino , Frequência do Gene , Genes , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo
2.
Trans R Soc Trop Med Hyg ; 77(6): 840-4, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6320506

RESUMO

Microanalysis of subcellular organelle marker enzymes was applied to cryopreserved lymphocytes (obtained and processed in the field) from East African blacks with moderate to severe malnutrition and subject to locally endemic parasitic and infectious diseases. An initial study demonstrated that activities of these enzymes, with the partial exception of catalase, were stable to cryopreservation. Cryopreserved and thawed lymphocyte specimens (1 to 3 X 10(6) viable cells) from 26 Africans and 20 Caucasian controls were studied. There was a highly significant decrease in 5'nucleotidase activity in these African subjects. Activity of another plasma membrane enzyme, gamma-glutamyl transferase, and of marker enzymes for other intracellular organelles, was not significantly different between the two groups, indicating that the nucleotidase alteration is highly specific. 5'Nucleotidase activity in a group of 17 East African blacks of high socio-economic status lay between the values obtained in the other two groups and was not significantly different from either. Further studies on 5'nucleotidase showed no evidence that the enzyme is functionally different in Africans. The differences in activity of this enzyme in Africans may reflect the known immuno-suppressive effects of infectious disease and malnutrition or may have a genetic basis which may in turn be associated with the pathogenesis of secondary immunodeficiency.


Assuntos
Síndromes de Imunodeficiência/enzimologia , Linfócitos/enzimologia , Nucleotidases/metabolismo , 5'-Nucleotidase , Adolescente , Adulto , População Negra , Criança , Doenças Transmissíveis/imunologia , Feminino , Humanos , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Quênia , Masculino , Pessoa de Meia-Idade , Doenças Parasitárias/imunologia , Desnutrição Proteico-Calórica/imunologia , Tanzânia
6.
Bull World Health Organ ; 52(3): 293-300, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1084799

RESUMO

The relative sensitivities of counterimmunoelectrophoresis (CIE) and haemagglutination assays for the detection of hepatitis B surface antigen (HB(s)Ag) and antibodies (anti-HB(s)) were compared. Twelve scientists from ten countries in Asia, Africa and the Pacific region participated in the study. The participants provided serum samples from 15 953 subjects comprising patients with acute and chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC), as well as blood donors and other normal individuals. For the detection of HB(s)Ag in a reference panel serum, immune adherence haemagglutination (IAHA) was slightly more sensitive than passive haemagglutination inhibition (PHI); CIE was the least sensitive. Mean HB(s)Ag frequencies in patients with acute hepatitis, chronic hepatitis, cirrhosis, and HCC were significantly higher than in healthy controls. Passive haemagglutination (PHA) was more sensitive than CIE for the detection of anti-HB(s). The frequency of anti-HB(s) in patients with HCC was significantly lower than that in the other groups. Mean anti-HB(s) frequencies in patients with acute hepatitis, chronic hepatitis, and cirrhosis were not significantly different from that in normal subjects. Subtyping of HB(s)Ag was performed by PHI. Among asymptomatic carriers the predominant HB(s)Ag subtype in northeast Asia was adr.In India, ayw predominated in carriers, with the demarcation between adr and ayw occurring west of Burma. In West Africa the only subtype detected was ayw, but in East Africa the majority subtype was adw. The r subtype was found only in Asian populations east of India and in Western Pacific populations. In Papua New Guinea all four subtypes were identified. With one possible exception, the subtypes of HB(s)Ag-positive patients with liver disease reflected the predominant type in each geographic location.


Assuntos
Anticorpos Antivirais/análise , Antígenos da Hepatite B/análise , Hepatite B/imunologia , Hepatopatias/imunologia , África , Ásia , Austrália , Contraimunoeletroforese , Testes de Inibição da Hemaglutinação , Testes de Hemaglutinação , Humanos , Ilhas do Pacífico
7.
Tissue Antigens ; 5(1): 52-8, 1975 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1138442

RESUMO

Studies were carried out on the distribution of HL-A antigens in 33 patients with Burkitt's lymphoma from several tribal groups in Kenya. The frequency of distribution of the HL-A antigens was not significantly different in these patients from that in a selected control population. Difficulty was experienced in the precise identification of some HL-A antigens in Africans using a Caucasoid serum panel, in particular those associated with HL-A7 and to a lesser extent, the "W19" complex.


Assuntos
Linfoma de Burkitt/imunologia , Antígenos HLA , Antígenos de Histocompatibilidade , Adolescente , Adulto , Criança , Pré-Escolar , Testes Imunológicos de Citotoxicidade , Feminino , Teste de Histocompatibilidade , Humanos , Quênia , Linfócitos/imunologia , Masculino
8.
Int J Cancer ; 15(1): 139-43, 1975 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1079203

RESUMO

Spontaneous rosette formation was observed in eight out of nine Burkitt lymphoma biopsies. These were examined fresh and/or after culture in vitro for up to 48 h. The percentage of rosettes varied from 3.7% to 38%. There was a tendency for the percentage of rosettes to increase with time in tissue culture. It is suggested that the rosette-forming cells are T-lymphocytes infiltrating the tumour and functioning as a host defence mechanism against the proliferating tumour cells.


Assuntos
Linfoma de Burkitt/imunologia , Reação de Imunoaderência , Imunidade Celular , Linfócitos T/imunologia , África Oriental , Biópsia , Linfoma de Burkitt/sangue , Linfoma de Burkitt/patologia , Células Cultivadas , Meios de Cultura , Humanos , Técnicas In Vitro , Fatores de Tempo
9.
Cytobios ; 18(70): 89-99, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-611002

RESUMO

Fresh blood lymphocytes from nine health donors have been compared with samples from the same donors, recovered after period of 2 to 21 months storage in liquid nitrogen, for the capacity to respond to a range of mitogens in vitro. A microculture assay was used, requireing aliquots of only 25,000 cells. The mean levels of 14C-thymidine uptake for fresh and frozen samples were closely comparable when the cells had been stimulated by PHA, Pokeweed or mitomycin-C-treated allogeneic lymphoblastoid cells. Lymphocytes from six East African donors, frozen by a very simple technique, were recovered after 3 or more years storage in liquid nitrogen. Five of the samples were in good condition as judged by cell viability and the capacity to form spontaneous 'E' rosettes with sheep erythrocytes. These five samples also responded extremely well to PHA, PWM and mitomycin-C-treated allogeneic lymphoblastoid cells using the microculture assay. This study extends the range of applications of cell banks in which small aliquots of blood lymphocytes are stored in liquid nitrogen for periods of several years.


Assuntos
Preservação de Sangue , Ativação Linfocitária , Linfócitos/imunologia , Adulto , Sobrevivência Celular , Concanavalina A , Feminino , Congelamento , Humanos , Lectinas , Masculino , Mitomicinas , Formação de Roseta
10.
Int J Cancer ; 15(1): 132-8, 1975 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1079202

RESUMO

Frozen aliquots of peripheral blood mononuclear cells from patients with Burkitt's lymphoma (BL) at various stages of the disease have been compared with samples from East African children who were healthy or who suffered from non-malinant disorders. Using the sheep-cell rosette test (which is believed to identify T-lymphocytes), we found a significant reduction in the proportion of rosette-forming cells (RFC) in the samples from untreated BL patients. After reduction of remission the difference between BL patients and controls was abolished. Rosette formation was more readily inhibited by anti-lymphocyte globulin (ALG) in samples from untreated BL patients than in controls. On induction of remission the rosette inhibition curve shifted towards the control values. The findings are compatible with the presence, in untreated BL, of a circulating factor which impairs the capacity of T-lymphocytes to form rosettes with sheep erythrocytes. It remains to be established whether the functional capacity of T-cells to protect the host against tumour proliferation is also impaired.


Assuntos
Linfoma de Burkitt/imunologia , Reação de Imunoaderência , Imunidade Celular , Linfócitos T/imunologia , África Oriental , Animais , Anticorpos Anti-Idiotípicos , Antineoplásicos/uso terapêutico , Linfoma de Burkitt/sangue , Linfoma de Burkitt/tratamento farmacológico , Criança , Pré-Escolar , Eritrócitos/imunologia , Feminino , Humanos , Técnicas In Vitro , Lactente , Masculino , Remissão Espontânea , Ovinos/imunologia
11.
Tissue Antigens ; 16(4): 326-32, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7466791

RESUMO

One-hundred-forty-one Blacks (135 unrelated) from Kenya and Tanzania have been tissue-typed (HLA-A, B and C loci) as part of a study of host factors involved in Burkitt's lymphoma and naso-pharyngeal carcinoma. Evidence is presented for the existence in this population of several B15-related antigens which together occur with a relatively high frequency of 30% in unrelated individuals. It is likely that these variants may include the antigens SV and perhaps Bu recently defined with population frequencies of under 1% in Caucasians. In the absence of monospecific typing sera, identification of these variants may be helped by their apparently strong association with C-locus antigens in Blacks. Recognition of these B15 variants has been largely responsible for reducing the proportion of unidentified or "blank" B-locus antigens in this population to only 6%. These findings substantiate and amplify previous reports suspecting the presence of such antigens in Blacks, and should facilitate studies of possible associations of disease with HLA in these populations.


Assuntos
Antígenos HLA/genética , África Oriental , Soro Antilinfocitário/imunologia , Variação Genética , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Soros Imunes/farmacologia , Polimorfismo Genético
12.
Pediatriia ; (11): 29-33, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2075042

RESUMO

The paper is concerned with an analysis of the data on the immune status in associated fairly grave pneumonia and the obstructive syndrome in 78 infants treated at the resuscitation department. Gross chances were revealed in nonspecific resistance and in the status of the cellular component of immunity. The use in the treatment of a single transfusion of autologous blood x-rayed outside the body promoted the patients' rapid egress from the critical condition as well as the early improvement of the immune system status.


Assuntos
Infecções Bacterianas/terapia , Síndromes de Imunodeficiência/terapia , Pneumonia/terapia , Insuficiência Respiratória/terapia , Doença Aguda , Infecções Bacterianas/sangue , Infecções Bacterianas/etiologia , Infecções Bacterianas/imunologia , Sangue/efeitos da radiação , Transfusão de Sangue Autóloga , Pré-Escolar , Cuidados Críticos , Humanos , Síndromes de Imunodeficiência/sangue , Síndromes de Imunodeficiência/complicações , Lactente , Pneumonia/sangue , Pneumonia/etiologia , Pneumonia/imunologia , Insuficiência Respiratória/sangue , Insuficiência Respiratória/etiologia
13.
Arch Virol ; 130(3-4): 327-34, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8517792

RESUMO

Isolation and partial sequencing of human T-lymphotropic virus type I (HTLV-I) variants from inhabitants of Papua New Guinea (PNG) and the Solomon Islands has confirmed the existence of virus infection in Melanesian populations. To determine the geographical distribution of seropositivity to HTLV-I in PNG we have tested 2907 serum and plasma samples collected between 1972 to 1991 from 16 different population groups. Samples were screened using a particle agglutination assay and confirmed by p21e-enhanced Western immunoblot (WB). From a total of 94 screen positive samples run on WB, 56 (60%) were confirmed positive (positive for both env and gag products) and 38 (40%) were WB-indeterminate (gag products only). The prevalence of WB-confirmed antibodies to HTLV-I in lowland and island populations ranged from 0 to 5.4%. There were no confirmed antibody positives in the highland populations surveyed. Geographically isolated populations living on the fringes of the highlands ranged in seropositivity from 0.2 to 5.8%. Two of the subjects surveyed gave WB antibody patterns characteristic of HTLV-II rather than HTLV-I infection.


Assuntos
Anticorpos Anti-HTLV-I/sangue , Infecções por HTLV-I/epidemiologia , Adolescente , Adulto , Testes de Aglutinação , Western Blotting , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Papua Nova Guiné/epidemiologia , Prevalência , Estudos Soroepidemiológicos
14.
Int J Cancer ; 26(2): 165-70, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6937447

RESUMO

In an area of Tanzania in which Burkitt's lymphoma (BL) is endemic, five families are described in which multiple cases of BL were found or BL occurred with other neoplasms. The patients include two brothers and one half-brother with BL, two brothers with BL, a woman with nasopharyngeal carcinoma (NPC) whose daughter had BL, a boy with BL whose sister developed chronic myelogenous leukaemia (CML), and a man with CML whose son developed BL. The two full-sib pairs with BL is significantly more than would be expected to have arisen by chance and the association of BL with NPC and CML among close relatives is remarkable in view of the rarity of the last two neoplasms in the study area. It is suggested that genetic factors may be important. It is suggested that genetic factors may be important in determining susceptibility to the three malignancies in this population, but the possibility that the clustering of cases within families may be due to local environmental factors cannot be excluded.


Assuntos
Linfoma de Burkitt/genética , Leucemia Mieloide/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Primárias Múltiplas/genética , Adulto , Linfoma de Burkitt/epidemiologia , Criança , Pré-Escolar , Cromossomos Humanos 21-22 e Y , Feminino , Humanos , Leucemia Mieloide/epidemiologia , Masculino , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Primárias Múltiplas/epidemiologia , Linhagem , Risco , Tanzânia
15.
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