Structural studies of murine I-E and human DR antigens.

The structures of murine I-E antigens from two strains of mice were compared to each other and to human DR antigens. Murine and human antigens were isolated by using allo- and xenoantiserum, respectively, and purified by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The murine I-E and human DR antigens consist of two polypeptide chains designated α and β. The E_α and DR_α chains display a high degree of amino acid sequence homology as do the E_β and DR_β chains, provided a gap is inserted at position 1 of the DR_β chain. Comparison of N-terminal sequences reveals several differences between the β chains of I-E antigens from the two strains of mice. In contrast no sequence differences between the two α chains are observed. In addition, comparison of tryptic peptides examined by isoelectrofocusing reveals several differences between the two E_β chains, but not between the two E_α chains. Thus, the polymorphism of murine I-E antigens and by analogy human DR antigens, may result from structural differences in the smaller (β) chain.     

Grading score system: A method for evaluation of the degree of senescence in Senescence Accelerated Mouse (SAM)

For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in     

Characterization of idiotopes on MOPC 315 IgA using monoclonal antiidiotypic antibodies

The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG_2a), A2(IgG₁), G3 (IgG_2b) and F1 (IgG_2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H³¹⁵ L³¹⁵ and F³¹⁵_V but not with free H³¹⁵, L³¹⁵, V³¹⁵_H or V³¹⁵₂. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H³¹⁵ and L³¹⁵. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H³¹⁵ which requires an interaction with either L³¹⁵ or L⁴⁶⁰ for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.     

Variant Philadelphia chromosome translocations in two patients with chronic myelogenous leukemia

Two patients with chronic myelogenous leukemia and new variant Philadelphia chromosome translocations are reported. In one case, a 41-year-old male, a 10;22 translocation was found in all bone marrow cells examined. Furthermore, the Y chromosome was missing in 90% of the analyzed metaphase cells. In the second patient, a 22-year-old male, all the marrow cells contained a complex rearrangement involving chromosomes No. 2, 9, and 22.     

Simultaneous detection of SCE and Q-bands on human chromosomes by a double-staining technique

Human lymphocytes were cultured for two cell cycles in the presence of bromodeoxyuridine (BrdU), and the resulting metaphase chromosomes were first stained with quinacrine mustard (QM) and then, immediately afterwards, with Hoechst 33258, without any intermediate destaining. Both Q-banding patterns and sister chromatid differential staining were photographed subsequently on the same metaphase using two different filter blocks of the fluorescence microscope.     

Ultrastructural responses by Golgi apparatus of rat submandibular gland to beta-adrenergic, alpha-adrenergic, and cholinergic stimulation

Rat submandibular gland tissue pieces were stimulated in vitro for 30 min with a beta-adrenergic agent or a cyclic AMP analog to stimulate protein secretion, or with alpha-adrenergic or cholinergic agents or a Ca2+ ionophore to stimulate fluid secretion. Acinar cells were examined by transmission electron microscopy. In control tissue, acinar cells showed little evidence of secretory activity. The Golgi apparatus was sparse and was associated with a few small, immature secretory granules with fine fibrillar contents. Following secretory granule discharge stimulated by isoproterenol or dibutyryl cyclic AMP, acinar cells were constricted, and had extensive basolateral membrane folding and tightly packed rough endoplasmic reticulum. Golgi complexes were prominent and had multiple small granules with filamentous contents. After stimulation of fluid secretion by alpha-adrenergic agents (epinephrine, phenylephrine), or cholinergic agents (acetylcholine, carbachol, pilocarpine), or a Ca2+ ionophore (A23187), the Golgi apparatus had compact concave cisternae enclosing aggregates of tubulovesicles. Acinar cells were distended, basolateral membranes were expanded, and rough endoplasmic reticulum was dilated and vesiculated.     

Papain-induced lung injury: alterations in connective tissue metabolism without emphysema

The acute effects of the deposition of papain in the lungs of 4-month-old rabbits have been investigated with an amount not sufficient to cause emphysematous changes. During the first 2 days of in vivo deposition when hemorrhaging and inflammation occur, the total amounts of collagen and elastin in the lung, into which the papain had been instilled, did not change but the concentrations of collagen and elastin decreased 20 and 25% respectively. The rates of synthesis of collagen and other proteins doubled. By 4 weeks, collagen and elastin concentrations returned to, or were slightly above, control levels. The histological appearance and mean linear intercepts of lung sections and the compliance curves of excised lungs of the treated animals were similar to controls by 2 weeks after papain administration. The rabbit lung thus appears able to repair mild injury due to proteolytic enzymes.     

Fine particulate matter exposure during pregnancy and infancy and incident asthma

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The use of detergents and immunoperoxidase reagents for the ultrastructural demonstration of internal immunoglobulin in lymph cells.

Lymph-borne immunoblasts were fixed in dilute glutaraldehyde and then treated with saponin. This treatment made most parts of the cells permeable to ferritin, so that anti-immunoglobulin (Ig) antibodies which had been conjugated to horse radish peroxidase (HRP) had no difficulty in gaining access to Ig which thus could be demonstrated at an ultrastructural level. Best results were obtained by fixing the cells in 0.1% glutaraldehyde for 7 min and then treating them with a 1% solution of saponin for 100 min at 55 degrees C before exposing them to the Ig-HRP conjugate. The method yielded reproducible results and although it causes a small amount of ultrastructural damage, it may be of value in detecting a variety of intracellular antigens.