SummaryWe report here on the evaluation of a factor I-deficient Brazilian family (three generations, 39 members) with strong consanguinity. The complete factor Ideficient patients ( n = = = = 3) presented recurrent respiratory infections, skin infections and meningitis; one of them died after sepsis. They presented an impaired total haemolytic activity (CH 50 ), low C3, low factor H and undetectable C3dg/C3d. Partial factor I deficiency was detected in 16 family members (normal low cut-off value was 25 μ μ μ μ g/ml). Respiratory infections were the most common clinical occurrence among partial factor I-deficient relatives. Two of them were submitted to nephrectomy following recurrent urinary tract infections. An additional two heterozygous relatives presented with arthritis and rheumatic fever. Apparently, patients with partial factor I deficiency are also at higher risk for recurrent infections. Vaccination against capsulated bacteria and the eventual use of prophylactic antibiotics should be considered individually in this patient group.

No abstract

We have evaluated the immune responses of individuals living in a malaria endemic area of Brazil to the (T1B)4, a multiple antigen peptide (MAP) from Plasmodium falciparum circumsporozoite (CS) protein and the related monoepitope MAPs, B4 and (T1)4, and the linear peptides, T1B and B. The highest antibody frequencies were against MAPs containing the B cell epitope sequence (T1B)4 (42.2%) and B4 (28.8%), while the highest lymphoproliferative response frequencies were against the MAPs containing the T cell epitope sequence (T1)4 (47%) and (T1B)4 (36.4%). We analysed individual responses considering lymphoproliferative response to (T1)4 MAP and IgG antibody titre to (T1B)4 as patterns of ideal cellular and humoral responses, respectively. The frequency of responders, cellular and/or humoral was 66.6%, significantly higher than non responders (P = 0.003). We also determined the HLA class II haplotype of each individual but no association between these and immune response patterns to the MAPs was observed. The results showed that individuals primed against P. falciparum in their natural habitat, present a very diverse array of responses against the same peptide antigens, varying from no response in one-third of the individuals to cognate B and T cell responses. Our study underlines the importance of previous studies of vaccine candidates to guarantee that the immunization will be capable of reverting inefficient or absent responses to malaria epitopes.

314CHAGAS KN ET AL. sendo mutações pontuais ou pequenas deleções ou inserções 3,4 . A maior função do C1-INH no corpo humano inclui a inibição direta da calicreína ativada, inibição do fator de Hageman (fator XII da cascata da coagulação) e prevenção da ativação do componente C1 do sistema complemento 5 . A diminuição da atividade de C1-INH permite a ativação de C1, com início da atividade, e consumo, de C4 e C2, resultando em diminuição de seus níveis séricos durante os ataques de HAE 6 . As formas de angioedema com deficiência de C1-INH são divididas em hereditárias e adquiridas. As hereditárias são decorrentes da produção deficiente do inibidor com função normal (tipo I) ou da produção de quantidade normal de C1-INH com função alterada (tipo II), o que corresponde a 85% e 15% dos casos, respectivamente. No tipo I, a região do gene rica em repetições Alu, sempre contém o gene defeituoso e isso explica porque pacientes do tipo I não produzem níveis normais de C1-INH e não há expressão de C1-INH. No tipo II, o defeito é usualmente localizado pró-ximo do sítio ativo ARG 444 ou no exon 8. Nas formas adquiridas (AAE) ocorre uma diminuição do C1-INH por aumento de seu catabolismo e, freqüentemente, estão associadas com doença linfoproliferativa e com a presença de anticorpo anti-C1-INH, sem doença de base detectável; a função de C1-INH está moderadamente diminuída e há resistência à reposição de C1 purificado 5,[7][8][9][10] . Uma redução acentuada na produção de C1q é considerada como marcador das formas adquiridas de angioedema, provavelmente por degradação através de ativação induzida por complexos anti-idiotipo/idiotipo 7 . Clinicamente, os pacientes com HAE usualmente tornam-se sintomáticos na segunda década de vida, apresentam grande variabilidade na freqüência dos episódios e a maioria dos ataques ocorre sem qualquer razão aparente, em três sítios principais: tecido subcutâneo, tratos gastrointestinal e RESUMO -OBJETIVOS. A primeira descrição clínica completa do angioedema hereditário (HAE) foi relatada por

The objective of the present study is to standardize the technical variables for preparation and storage of Plasmodium falciparum and of antigen components extracted with the amphoteric detergent Zwittergent. P. falciparum obtained from in vitro culture was stored at different temperatures and for different periods of time. For each variable, antigen components of the parasite were extracted in the presence or absence of protease inhibitors and submitted or not to later dialysis. Products were stored for 15, 30 and 60 days at different temperatures and immunological activity of each extract was determined by SDS-PAGE and ELISA using positive or negative standard sera for the presence of IgG directed to blood stage antigens of P. falciparum. Antigen extracts obtained from parasites stored at -20 degrees C up to 10 days or at -70 degrees C for 2 months presented the best results, showing well-defined bands on SDS-PAGE and Western blots and presenting absorbance values in ELISA that permitted safe differentiation between positive and negative sera.