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A new animal model to study secondary intention wound healing and the effects of topically applied rhTGF-beta 1 was developed. A time course study was performed of full thickness 6 mm punch wounds placed on the backs of anesthetized pigs and treated once with either 3% methylcellulose or rhTGF-beta 1 in 3% methylcellulose or left untreated. Wounds receiving rhTGF-beta 1 had enhanced tensile strength at days 4 and 7 compared to controls. Studies of the response on days 4 and 7 to graded doses of rhTGF-beta 1 showed that a dose of 250 or 2500 ng rhTGF-beta 1 gave a similar enhanced wound strength, while 25 ng rhTGF-beta 1 had no effect. Blood flow to treated granulating wounds as measured by 141Ce microspheres indicate an increase in flow in wounds treated with 250, 500 or 2500 ng rhTGF-beta 1 compared to controls. These results indicate a possible use for rhTGF-beta 1 in enhancing wound healing clinically.

Breast milk, particularly colostrum, has significant quantities of antibody-containing immune globulins. The antibodies secreted by the breast are chiefly in the yA globulin and parallel the elevated levels of yA globulin in colostrum or breast milk( 1).Studies indicating absorption of intact proteins ( 2 ) and antibodies (3) from the gastrointestinal tract led us to reinvestigate whether colostral or breast milk immune globulins, particularly yA, are absorbed intact to any significant degree. We, therefore, compared the serum concentration of yG, yM, yA of breast-fed and formula-fed infants and determined the concentration of immune globulins in colostrum and breast milk.Medhods. Cord serum was obtained from 10 full-term infants who were subsequently breast-fed and from 10 full-term infants given formula feedings. A second serum sample was obtained at 4 days from each infant. During this period the mean weights of the breastfed infants fell from 3280 to 3160 g and of the formula-fed infants from 3100 to 3060 g. Samples of breast milk from the mothers of these infants, obtained during the first 24 hours after delivery and for 3 days thereafter, were frozen immediately and stored at -1OOC.Immune globulin levels were measured quantitatively by the radial diffusion technic of Mancini and associates (4) with specific antiserum to yG, y M and ?A globulin incorporated into agar plates. Purified immune globulins quantified by Kjeldahl nitrogen analysis were used as standards. In this laboratory, the method has an error of 3% when samples are tested in duplicate on the same plate or 10% when duplicate samples are tested on different plates. In adults, the normal values by this method(5) are as follows :yG 1158 mg/100 ml t 305 yM 99 mg/100 ml -4 27 yA 200 mg/100 ml t 61 The student T test was used for statistical comparison.Resdts. Fig. 1 illustrates the changes in immune globulin concentration in breast secretions during the first 4 days of transition from colostrum to mature breast milk.The mean values (ml/lW rnl) for initial colostrum (YG 43, yM 159 and yA 1735) compared to fourth-day post-partum breast milk (YG 4, yM 10 and yA 100) indicate a high content of yA in colostrum and a small amount of yG globulin.The immune globulin levels of formula-fed and breast-fed infants were not significantly different (Table I ) nor were there significant differences between cord and 4-day serum. Only 2 infants demonstrated detectable yA in cord and 4-day serum.Assuming a 2 5% intravascular distribution (6) and a plasma volume of 50 ml/kg, absorption of 60 mg yA globulin from the gasat UNSW Library on July 12, 2015 ebm.sagepub.com Downloaded from

T-helper:T-suppressor cell ratios of 1 or less were found in 2 of 42 homosexual men without antibodies to cytomegalovirus but in 33 of 67 homosexual men with antibodies (p less than 0.001). Of 34 men without antibody who were followed prospectively, 12 became seropositive for cytomegalovirus and all 12 developed helper: suppressor ratios of less than 1.0. These ratios remained at 1 or less for an average of 9.6 months but persisted for 15 months or more in 3 men. None of the men in the prospective study developed antibodies to the acquired-immunodeficiency-syndrome-associated retrovirus. These results indicate that in the homosexual men studied, abnormally low T-lymphocyte helper: suppressor ratios occurred almost exclusively in those who were infected with cytomegalovirus, and in those prospectively followed low ratios did not reflect contact with the syndrome-associated retrovirus. Abnormal ratios were rarely seen in men who had never been exposed to cytomegalovirus. Thus, cytomegalovirus infection may be an important cofactor in the immunologic disorders leading to the acquired immunodeficiency syndrome.