Serological properties of γA antibodies to Escherichia coli present in human colostrum

Antibodies against Esch. coli WF 96 and WF 61 present in human colostrum and serum were fractionated by DEAE-cellulose chromatography. Using the haemagglutination test it was found that the antibodies present in colostrum were recovered in the fraction containing the bulk of γA-globulin, whereas the antibodies present in serum were recovered in the fraction containing the bulk of γM-globulin. In the presence of human or guinea-pig complement the antibodies present in colostrum did not lyse red cells coated with bacterial polysaccharides whereas the antibodies present in serum were lytic.

When the properties of γA and γM antibodies were studied using a bacteriolytic system, it was observed that γA-globulin lysed bacteria only in the presence of both complement and lysozyme; in this respect γAbacterial antibodies behaved differently from γM antibodies which were bacteriolytic in the presence of complement alone, without lysozyme.

The effect of treating γA and γM antibodies with 2-mercaptoethanol at neutral pH and of heating at 56° was investigated.

     

Resistance to infection: looking for new genes

Genetic factors in resistance to infection, somewhat neglected with the development of microbiology, are again receiving careful attention. Although there are numerous reports of infection resulting from deficiencies in, for example, immunoglobulins or complement components, specific abnormalities in resistance associated with particular HLA groups have been unexpectedly rare. In mice, the Ity gene on chromosome 1, which is important in resistance to Salmonella typhimurium infection, may well be identical with the Lsh and Bcg genes concerned with resistance to Leishmania donovani and Mycobacterium bovis BCG. The most likely common factor determining resistance to three such disparate organisms is the macrophage, but direct evidence of its role is lacking. The high and low antibody-producing strains of mice selected by BIOZZI [2] are respectively sensitive and resistant to many intracellular infections including S. thyphimurium. Experiments with hybrids between Biozzi mice and other inbred strains suggest that the high line carries the Itys (salmonella susceptibility gene) plus another gene increasing susceptibility. Low line mice carry the Ityr gene plus another gene increasing resistance. Inbred mice are invaluable for analogizing gene interactions which, once understood, can be looked for in man.     

The 2000 Burkitt lymphoma trial in Malawi

BACKGROUND: We previously reported 57% 12-month event free survival (EFS) in Malawian children with stage I to III Burkitt lymphoma (BL) with an intermediate dose chemotherapy protocol lasting 77 days. This protocol was shortened to 42 days and evaluated in children with stage I to IV disease for EFS and toxicity. METHODS: All Malawian children admitted to Queen Elizabeth Central Hospital, from 03/08/2000 to 12/03/2002 with confirmed BL were eligible. A fine needle aspirate, bone marrow aspirate, cerebrospinal fluid cytology, haemoglobin (Hb), white cell count (WCC), malaria smear, ELISA for HIV, and abdominal ultrasound were performed routinely. Murphy staging was used. The first dose of chemotherapy (COP1) consisted of 300 mg cyclophosphamide (CPM), 1 mg vincristine, and 60 mg prednisone given on day 1 and followed by COP2 on day 8 (only for patients with larger tumour volumes, stage III or IV disease). The vincristine dose in COP2 was 2 mg. COMP1 and 2 given on days 22 and 36 consisted of 500 mg CPM, 2 mg vincristine, 60 mg prednisone, and 2 g methotrexate. All doses were calculated per body surface area. Intrathecal methotrexate and hydrocortisone were given with COP1 and 2. RESULTS: Forty-two patients, 30 boys and 12 girls median ages 6 and 7.5 years, respectively, had Murphy stage I(n5), II(n8), III(n21), and IV(n8) disease. The face was involved in 74%, abdomen in 55%, bone marrow in 14%, kidneys in 24%, and 12% had paraplegia. Fourteen children died during or shortly after completion of chemotherapy. Three of these were disease related. Twelve patients suffered a local relapse after 57-328 days, and one a CNS relapse at 76 days. The projected EFS at 12 months is 50% in stage I, 50% in stage II, 24% in stage III, 25% in stage IV, and 33% for all patients. The cumulative mean dose of CPM was 62 mg/kg in survivors and 64 mg/kg in children who relapsed. One third of patients experienced significant marrow suppression, and infections after COMP1. CONCLUSIONS: Thirty-three percent of children are in first remission at 12 months. The morbidity and mortality of treatment was high. The high relapse rate in all stages may be due to the low cumulative dose of CPM.     

ABO and Rh(D) phenotype frequencies of different racial/ethnic groups in the United States

BACKGROUND: Commonly quoted ABO/Rh(D) frequencies in the US are usually from relatively small studies with racial or ethnic categories often judged by name or appearance. STUDY DESIGN AND METHODS: A 10-year demographic database that contained racial or ethnic and ABO/Rh(D) phenotype data on 3.1 million allogeneic and autologous donors giving blood at five blood centers in the US was used to compute ABO and Rh(D) phenotypes in various racial/ethnic groups. The racial or ethnic category was designated by the donor. RESULTS: The highest percentage of Group O was found in Hispanic (56.5%), North American Indian (54.6%), and black non-Hispanic (50.2%) donors. Hispanic and black non-Hispanic donors had a much lower percentage (7.3 and 7.1%, respectively) of Rh- compared to white non-Hispanic donors (17.3%). Group O Rh- and Group B Rh- were found more commonly (8.0 and 1.8%, respectively) in white non-Hispanic donors than in Hispanic (3.9 and 0.7%), black non-Hispanic (3.6 and 1.3%), and Asian (0.7 and 0.4%) donors. CONCLUSIONS: These data confirmed that the highest percentages of ORh+, BRh+/ABRh+, and Rh- are present in Hispanic, Asian, and white non-Hispanic donors, respectively. These are the largest and most accurate data of ABO/Rh(D) phenotype frequencies for the major racial/ethnic donor groups in the US.     

Age-related cataract in a randomized trial of beta-carotene in women

PURPOSE: To examine the development of age-related cataract in a trial of beta-carotene supplementation in women. METHODS: The Women's Health Study is a randomized, double-masked, placebo-controlled trial originally designed to test the balance of benefits and risks of beta-carotene (50 mg on alternate days), vitamin E, and aspirin in the primary prevention of cancer and cardiovascular disease among 39,876 female health professionals aged 45 years or older. The beta-carotene component of the trial was terminated early after a median treatment duration of 2.1 years. Main outcome measures were visually-significant cataract and cataract extraction, based on self-report confirmed by medical record review. RESULTS: There were 129 cataracts in the beta-carotene group and 133 in the placebo group (relative risk [RR] = 0.95, 95% CI 0.75-1.21). For cataract extraction, there were 94 cases in the beta-carotene group and 89 cases in the placebo group (RR = 1.04, 95% CI 0.78-1.39). Subgroup analyses suggested a possible beneficial effect of beta-carotene in smokers. CONCLUSIONS: These randomized trial data from a large population of apparently healthy female health professionals indicate that two years of beta-carotene treatment has no large beneficial or harmful effect on the development of cataract during the treatment period.