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A serum raised by immunizing (B10.A(4R) X B10.HTT)F1 mice against A.AL lymphocytes detects a new antigenic determinant designated Ly-22.2. Ly-22.2 expression is under the control of two independently segregating genes, one of which maps to chromosome 4 adjacent to a locus affecting XenCSA expression. Ly-22.2 is present in varying amounts in all lymphoid organs, but appears to be expressed primarily on T lymphocytes. Ly-22.2 is not detectable in brain, kidney, lung, liver, or erythrocytes. Strain distribution studies show Ly-22.2 is present in all strains examined except B10-derived congenic strains. It is of interest that C57BL/6 and C57BL/10 mice differ in the expression of this antigen.

Trypsin digestion of pilin monomers from EDP208 conjugative pili causes cleavage of Lys12 to yield an N-terminal dodecapeptide, ET1 (Mr approximately equal to 1,500), and the remaining C-terminal fragment, ER (Mr approximately equal to 10,000). Using the amino acid sequence for ET1 provided by Frost et al. (J. Bacteriol. 153:950-954), we synthesized the N-terminal dodecapeptide chemically, conjugated it to bovine serum albumin, and subjected it to immunological studies. Antisera prepared against intact EDP208 pili as well as against the synthetic ET1-BSA conjugate were used in experiments involving an enzyme-linked immunosorbant assay and electrophoretic transfer of proteins from sodium dodecyl sulfate-polyacrylamide gels to nitrocellulose sheets. Both experimental approaches showed strong reactivity between the synthetic dodecapeptide and antiserum raised against whole pili. It was also found that antiserum raised against the synthetic peptide was reactive against intact pilus protein, indicating that the N-terminal dodecapeptide is an important antigenic determinant of the EDP208 pilus protein. Additional studies showed that the C-terminal fragment, ER, may contain one or two additional antigenic sites.

Treating mature rat uterine cytosol with dextran coated charcoal (DCC) for 2 hrs at 0-4C in the absence of ligand causes the subsequently formed receptor-estradiol complex to be stable at 37C. Receptor binding is increased by the DCC treatment for uteri excised at metestrus or diestrus but remains nearly unchanged for uteri obtained at proestrus or estrus. Results suggest that the DCC removes or inactivates factor(s) present in the cytosol which render the receptor complex thermolabile.

The concentrations of Zn2+, Ca2+, Mg2+, Pi and adenine nucleotides were determined in insulin-secretory granules prepared from a transplantable rat insulinoma. Differential and density-gradient centrifugation analyses revealed that Zn2+ in this tissue was principally localized in the secretory granule, a second major fraction being found in association with cytosolic proteins. Pi was principally recovered in the latter fraction, whereas Ca2+ and Mg2+ were more widely distributed. Intragranular ion-distribution experiments suggested that Zn2+ was complexed mainly to insulin and its precursor forms and remained in the granule in an insoluble state. The Zn2+/insulin ratio (0.54) was greater than that expected for insulin molecules having two centrally co-ordinated Zn2+ atoms/hexamer, but less than the maximal Zn2+-binding capacity of the molecule. Most of the granular Ca2+, Mg2+ and Pi was released in a soluble form when granules were disrupted by sonication. Simulation in vitro of the ionic composition of the granule suggested that up to 90% of its Ca2+ was complexed to Pi and adenine nucleotides. Granular macromolecules also bound Ca2+, as shown by equilibrium-dialysis studies of granule lysates. However, such binding was displaced by Mg2+. Examination of the efflux of Ca2+ from granules incubated in iso-osmotic suspensions at 37 degrees C suggested that the passive permeability of the granule membrane to Ca2+ was very low. Nevertheless, more than 50% of the granular Ca2+ was rapidly released in an ionized form on hypo-osmotic or detergent-induced disruption of the granule membrane. This may represent a potentially mobilizable pool of Ca2+ in vivo.

Statistical features of the method of antigen genotype frequencies among the diseased, for single and multiple disease associations at a locus, will be presented. A methodology to determine when a true intermediate mode of inheritance can be distinguished from strict recessive or additive inheritance will be developed. The effect of sporadics and ascertainment bias on the observed antigen genotype frequencies will be investigated. Data on ankylosing spondylitis, multiple sclerosis and dermatitis herpetiformis are very close to expectations for an additive (or dominant) mode of inheritance for the HLA-linked disease-predisposing gene, and data on hemochromatosis, insulin dependent diabetes mellitus and celiac disease are close to recessive expectations. If an intermediate model does apply in any of these cases, it must be an intermediate model that is fairly close to a strict recessive or dominant model; as appropriate. DR data for insulin dependent diabetes mellitus (IDDM) strongly indicate that there are two separate "disease" alleles, which exhibit negative complementation, predisposing individuals to IDDM, where the mode of inheritance of the "disease" alleles considered separately is close to recessive. In general, this method cannot rule out the existence of sporadics or a second disease-predisposing gene, when the penetrance values over the two disease-predisposing genes are strictly additive, for diseases showing agreement with additive (or dominant) modes of inheritance.

Cytoplasmic receptors for 17 beta-estradiol (ER) and progesterone (PR) were measured in uterine cervical, vaginal, and vulvar carcinomas by the dextran-coated charcoal (DCC) technique. Tissues from 30 patients with cervical carcinoma were examined. Thirteen percent (2 of 16) of well-differentiated squamous carcinomas had positive ER, and 19% (3 of 19) had positive PR. None of the three patients with moderately well-differentiated disease have positive ER or PR, while two of five patients with poorly differentiated lesions contained measurable ER and PR. In contrast, all four of the well-differentiated adenocarcinomas of the cervix had detectable ER, and three of four for PR. Neither of the two patients with poorly differentiated adenocarcinoma had either ER or PR. None of the five vulvar and seven vaginal epidermoid carcinomas studied had ER or PR activity. Hormonal therapies may be useful in the treatment of adenocarcinoma of the cervix.

In this report we further show the utility and efficiency of polymer-bound 1-hydroxybenzotriazole (PHBT) as an almost ideal support for the polymeric reagent method of peptide synthesis. This was demonstrated by the synthesis of thymosin alpha 1 (15-28), in which two suitably blocked segments, Boc-Asp (OtBu)-Leu-Lys (2Cz)-Glu (OBzl)-Lys (2Cz)-Lys (2Cz)-OH (3) and Boc-Glu (OBzl)-Val-Val-Glu (OBzl)-Glu (OBzl)-Ala-Glu (OBzl)-Asn-OBzl (2), were prepared entirely by utilizing PHBT activation for each coupling step. After appropriate deblocking of 2, segments 2 and 3 were coupled by the DCC-HOBT method, followed by complete deblocking and ion-exchange chromatographic purification, affording the C-terminal half of thymosin alpha 1, H-Asp-Leu-Lys-Glu-Lys-Lys-Glu-Val-Val-Glu-Glu-Ala-Glu-Asn-OH (1).