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A medium conditioned by leukocytes in the presence of phytohemagglutinin (PHA-LCM) promotes the growth of human multilineage hemopoietic progenitors (CFU-GEMMT) which form mixed hemopoietic colonies in culture containing granulocytes, erythroblasts, megakaryocytes, macrophages, and T-lymphocytes. PHA-LCM derived from six HLA-typed patients with idiopathic hemochromatosis and from six normal individuals were tested for growth-promoting activities for multilineage hemopoietic colony formation. Four out of six conditioned media obtained from patients with hemochromatosis supported mixed hemopoietic colony formation, as did four of six conditioned media from normal HLA-typed volunteers. Active PHA-LCM preparations from patients with hemochromatosis were similar with respect to the number and size of mixed colonies and their cellular composition when compared with conditioned media obtained from volunteers. The study indicates that no link exists between the HLA phenotype of a particular donor and the predictability of obtaining an active PHA-LCM promoting multilineage hemopoietic colony formation. PHA-LCM derived from patients with hemochromatosis had no advantage with respect to stimulatory activity for mixed colony formation when compared with conditioned media obtained from healthy volunteers.

A radioactive crosslinking reagent, N-[4-(p-azido-m-[125I]iodophenylazo)benzoyl]-3-aminopropyl-N' -oxysulfosuccinimide ester, has been synthesized. The reagent is photoactivatable, water-soluble, cleavable through an azo linkage, and labeled with 125I at the carrier-free specific activity of 2000 Ci/mmol. Any protein derivatized with the reagent is thus converted into an 125I-labeled photoaffinity probe. Crosslinks are formed following photolysis with 366-nm light, and cleavage by sodium dithionite results in the donation of radioactivity to the distal partner in crosslinked complexes. The newly labeled proteins are then analyzed by gel electrophoresis and autoradiography. The compound was prepared by iodination of N-[4-(p-aminophenylazo)benzoyl]-3-aminopropionic acid using carrier-free Na125I and chloramine-T, followed by azide formation and conversion to the water-soluble sulfosuccinimide ester. As a model system, protein A-Sepharose was derivatized with the reagent under subdued light. Each derivatized protein A molecule contained only one crosslinker. The derivatized protein A-Sepharose was then photolyzed in the presence of human serum and subsequently treated with sodium dithionite. Analysis of the serum by gel electrophoresis revealed that 1.1% of the radioactive label originally present on the protein A-Sepharose was transferred to the heavy chain of IgG, which was the most intensely labeled protein in the gel. The next most intensely labeled protein was IgG light chain, which incorporated radioactivity that was lower by a factor of 3.6 than that of the heavy chain. These results demonstrated the specificity of the derivatized protein A-Sepharose as a photoaffinity probe. Photolabeling of IgG was the result of nitrene-mediated reactions and was not due to the incorporation of free 125I.

Before establishing the diagnosis of chronic active hepatitis (CAH) non-A-non-B other diseases have to be excluded, like toxic hepatitis (alcohol, drugs), immunological forms (autoimmune hepatitis, primary biliary cirrhosis), and metabolically caused hepatitis (hemochromatosis, Wilson's disease), since for some of these patients specific therapeutic procedures are available. History of the disease and repeated evaluation of control biopsies performed about every 9 to 12 months help in deciding about therapy. Chronic persisting hepatitis non-A-non-B and the mild form of CAH non-A-non-B do not need treatment but only diagnostic follow-up. Patients with apparent clinical disease, increased transaminases and histologically typical findings in at least two biopsies may be looked at as suitable for drug treatment. Since this disease is probably caused by virus, immunosuppressive therapy in this small group of patients described above has to be temporarily limited and should not be used as long term treatment.

The published data concerning changes of antithrombin III (ATIII) in nephrotic syndrome (NS) are contradictory. While increased ATIII activity has been reported by some investigators, decreased concentration has been shown by others and normal values by yet another group of authors. We determined plasma and urine concentrations of ATIII in a group of 20 patients with NS using an immunologic assay. In addition, plasma ATIII activity was determined. The results were compared with those obtained in a group of normal volunteers. Plasma concentration and activity of ATIII were both greatly reduced in the patients with NS. In addition, substantial quantities of ATIII were recovered in the urine of all tested patients. The present study, therefore, substantiates the low plasma concentrations of ATIII and its urinary losses in NS. In addition, a parallel reduction in plasma ATIII activity is demonstrated providing functional evidence of acquired ATIII deficiency in this condition.

Neither autoradiography nor in vitro labeling of thin sections of tumor tissue can be used for the quantitative determination of radioactive labeled cytoplasmic hormone receptor. The acknowledged method for his purpose is the DCC (Dextran Coated Charcoal) method. Hormone receptor estimations are routinely used to predict those patients with hormone-dependent tumors who will respond to endocrine therapy. Some 80% of patients with positive estrogen and progesterone receptor show objective remissions after endocrine therapy. Receptor determinations are carried out routinely in patients with mammary, uterine or ovarian carcinoma to identify those subjects who would benefit most from endocrine therapy.

Erythrocytosis, increased whole blood oxygen affinity, and iron overload were found in a 37-yr-old man. Electrophoretic techniques to demonstrate a hemoglobin variant showed no abnormality. Structural studies of the hemoglobin from this patient revealed an abnormal hemoglobin previously described as Hemoglobin Olympia, a high-affinity variant. Study of three generations in this family showed increased hepatic iron or iron absorption in some members of all three generations studied. The findings in this family are consistent with an increase in iron absorption due to the consequences of Hemoglobin Olympia and the heterozygous state for hemochromatosis (allele for hemochromatosis associated with HLA-A3, B7) or the presence in the family pedigree of three different alleles for hemochromatosis (alleles for hemochromatosis associated with HLA-A3. B7, HLA-A3, B15, and HLA-A9, B44) with the heterozygous state being manifest with increased iron absorption.