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A cohort of 760 newborns was followed prospectively for 2 years to ascertain the time of administration of childhood vaccinations in rural Malawi and to study predictors of non-compliance with national vaccination recommendations. At 1 year of age, 99% of the infants were fully vaccinated against tuberculosis, 91% against polio, 90% against diphtheria, pertussis and tetanus and 64% against measles. At 2 years, the corresponding vaccination coverages were 99%, 93%, 93% and 84%. On average, all vaccinations were given 1-3 months later than recommended. Many of the delayed measles vaccinations were given during a separate vertical campaign, during which 25% of previously unvaccinated 21-23-month-old children were identified and immunized. Non-compliance with vaccination recommendations was associated with living in villages with no access to mobile vaccination teams, birth between April and June and birth at home. In this rural Malawian area, most vaccination services were functioning well. To increase measles vaccination coverage, regular outreach activities should be encouraged.

HMFG antigen is a tumour associated glycoprotein that has been immunohistochemically shown to be expressed by malignant cells in breast and ovarian and to a lesser degree in gastro-intestinal carcinomas. We have developed a non-isotopic sandwich ELISA for secretory HMFG antigen utilizing a polyclonal catcher and a tracer monoclonal antibody (MAb). 52/52 of healthy medical students (controls) had a serum value under 400 U/ml whereas 15/30 patients (50%) with evident ovarian cancer and 13/37 (35%) with advanced breast cancer had a value exceeding 400 U/ml. From other patients with malignant tumours 2/14 (14%) with endometrial carcinoma, 0/5 with cervical carcinoma, 0/5 with vulvar carcinoma, 1/33 with gastro-intestinal carcinoma, 0/4 with oesophageal carcinoma and 2/45 of patients with leukemia or lymphoma had an elevated serum HMFG value. Four cases of Crohn disease, 3 cases of ulcerative colitis and 2 cases of pelvic inflammatory disease all showed a serum value below 400 U/ml. Progression of ovarian cancer was accompanied by increasing serum HMFG antigen levels. The antigen detected by our assay is different from CA 125 but may be related with the tumour associated antigen CA 15-3.

Human immunodeficiency virus (HIV)-specific helper T-cell response was studied in human subjects and nonhuman primates either infected with HIV or immunized with different HIV protein preparations. A strong group-specific T-cell response involving T-cell proliferation and lymphokine secretion was observed in immunized chimpanzees and rhesus monkeys as well as HIV-infected chimpanzees and gibbons. HIV-infected people demonstrated a low or no HIV-specific T-cell response. In contrast, five of 14 HIV antibody-negative sexual partners of HIV-infected men recognized one or more T-cell epitopes in the envelope glycoprotein of HIV.

We conducted a nutritional survey to describe monthly variation in food consumption among subsistence farmers in Malawi, Southeastern Africa. Of special interest was the identification of foods whose intake changes contributed most to the seasonal fluctuation of overall energy intake. For this purpose, dietary intakes of 593 pregnant women were analysed with 24-h recall methodology. Mean daily energy intakes varied from 1520 kcal/woman in February (rainy season) to 2250 kcal/woman in April (post-harvest period). On average, maize provided two-thirds (63%) of the energy. Other important sources were roots and tubers (11%), fish (5%), fruit (4%), legumes (4%) and vegetables (3%). The rainy season decrease in energy intakes was associated with a marked reduction in the consumption of roots and tubers, fruit, legumes and vegetables. Storage of selected food items and development of agricultural market could alleviate nutritional problems associated with climatic seasonality in rural Malawi.

Poor complementary feeding practices are associated with stunting and growth faltering throughout the developing world. The objective was to compare the effect of using peanut-/soy-based fortified spread (FS) and corn porridge fortified with fish powder (FP) as complementary foods on growth in rural Malawian children. A total of 240 children were enrolled at the age of 6 mo and randomized to receive FS or FP. Both complementary foods provided 836 kJ/d from 6 to 9 mo of age and 1254 kJ/d from 9 to 18 mo of age. Children were followed monthly for anthropometry and fortnightly for the symptoms of fever, cough, or diarrhea until they were 18 mo old. Zn and Se status were assessed at 6 and 12 mo. The primary outcomes were the rates of weight and length gain from 6 - 12 mo and from 12 - 18 mo. Children who received FS gained 110 g more (95% CI 220 to 10) from 6 - 12 mo of age than children receiving FP. Weight gain did not differ between children receiving FS and FP between 12 and 18 mo of age, nor did statural growth from 6 to 12 mo or 12 to 18 mo. A total of 23% of all children were Zn deficient at 6 mo of age and this increased to 37% at 12 mo of age. Neither FS nor FP was associated with significantly improved Zn status. FS was associated with better weight gain from 6 - 12 mo of age and may be useful in conjunction with additional interventions to improve infant growth in the developing world.

Polyclonal and monoclonal antibodies were used to characterize human milk fat globule (HMFG) membrane antigens, using gel filtration, ion exchange chromatography and western blotting. Although originally generated against HMFG, monoclonal antibodies also reacted with skim milk. In western blotting, several antigen molecules were seen, of which some were detected by all available antibodies, and one only with monoclonal antibody Ill D 5, previously shown to react with mammary and ovarian carcinomas bearing estrogen receptors. This or these antigens, with a molecular weight of about 53 kd, were isolated by fractionation in SDS-PAGE. A low polypeptide content was demonstrated but the antigenic structure could be stained with periodic-acid-Schiff and biotinylated peanut agglutinin, indicating the presence of galactose or N-acetylgalactosamine residues. While this 53-kd molecule is the only determinant exclusively stained by III D 5 antibody, it is suggested that it carries epitopes related to estrogen receptor activation.

Monoclonal antibodies generated against human milk fat globule membrane antigens were used in antibody-guided tumour imaging and palliative therapy in a case of wide-spread ovarian carcinoma. Antibody III H 2, which previously has been shown to react with 100% of ovarian cystadenocarcinomas showed a strong reactivity with tissue sections obtained from the primary and metastatic tumours of the patient. Immunoglobulins were purified from mouse ascitic fluid containing III H 2 and labelled with 123I or 131I with the iodogen method. 80 MBq (2 mCi) of 123I-labelled antibody was given intraperitoneally in 500 ml of PBS and the uptake of radiolabel was followed daily with emission tomography. Radiolabel was mainly located in the peritoneal cavity; only a very low activity was seen in the thyroid gland and urinary bladder. A therapeutic dose consisting of 600 MBq (15 mCi) of 131I-labelled antibody was followed nine days later and the localization of the antibody was followed.

The tumour antigen expression of ovarian and endometrial endometrioid carcinomas, ovarian clear-cell carcinomas as well as endometrial and cervical clear-cell carcinomas were immunohistochemically compared. Of special interest were potential differences between the endometrioid and clear-cell carcinomas of the ovary. The expression of CEA and CA 19-9 tumour antigens in all these tumour types was heterogeneous, with 10-20% of the cases being positive for CEA and 40-75% being positive for CA 19-9. In contrast, HMFG IIIC 12, a monoclonal antibody originally directed against human milk fat globule (HMFG) membrane antigens, invariably detected a corresponding antigen on every case of these tumour types. Another HMFG antibody, SM IF 3, on the other hand, detected antigenic material on all clear-cell tumour types, but only rarely on endometrioid tumours of the ovary or endometrium. While HMFG IIIC 12 detects an antigen present on all ovarian, endometrial and mammary carcinomas, antibody SM IF 3 thus appears to be more restricted in its staining patterns. Our results with both of these antibodies indicate that ovarian clear-cell carcinomas and ovarian endometrioid carcinomas have antigenic differences, which provides further evidence that they belong to different tumour entities.

Human immunodeficiency virus (HIV) infects human cells by binding to surface CD4 molecules and directly fusing with the cell membrane. Although mouse cells expressing human CD4 bind HIV, they do not become infected, apparently because of a block in membrane fusion. To study this problem, we constructed a recombinant vaccinia virus that can infect and promote transient expression of full-length CD4 in mammalian cells. This virus, together with another vaccinia recombinant encoding biologically active HIV envelope glycoprotein gp160, allowed us to study CD4/gp160-mediated cell-cell fusion in a wide variety of human and nonhuman cells in the absence of other HIV proteins. By using syncytium formation assays in which a single cell type expressed both CD4 and gp160, we demonstrated membrane fusion in lymphoid and nonlymphoid human cells but not in any of the 23 tested nonhuman cell types, derived from African green monkey, baboon, rabbit, hamster, rat, or mouse. However, in mixing experiments with one cell type expressing CD4 and the other cell type expressing gp160, all of these nonhuman cells could form CD4/gp160-mediated syncytia when mixed with human cells; in 20 of 23 cases, membrane fusion occurred only if the CD4 molecule was expressed on the human cells whereas in the other three cases, CD4 could be expressed on either one of the fusing partners. Interestingly, in one mouse cell line, CD4-dependent syncytia formed without a human partner, but only if a C-terminally truncated form of the HIV envelope glycoprotein was employed. Our results indicate that nonhuman cells are intrinsically capable of undergoing CD4/gp160-mediated membrane fusion, but this fusion is usually prevented by the lack of helper or the presence of inhibitory factors in the nonhuman cell membranes.