Edward Jenner, MD, and the scourge that was

This article was inspired by the global eradication of smallpox in 1980. Rather than reiterate the recent history of this remarkable achievement, we have chosen to celebrate the event by reviewing the early history of smallpox immunization and the contribution of Edward Jenner, MD, to this endeavor. In addition, we present these historical events within the context of knowledge acquired by modern virologists.

Assays for the Sm and RNP autoantigens: the requirement for RNA and influence of the tissue source

The disease systemic lupus erythematosus is characterized by antibodies directed against two nuclear antigens, designated Sm and RNP. The two antigens from any one tissue can be distinguished on the basis of the polypeptides recognized by anti-Sm and anti-RNP specific sera. Multiple polypeptides were associated with RNP isolated from rabbit thymus. To determine if these polypeptides were species-specific, a comparison was made of this antigen among different mammalian species. We report that the native RNP antigen has a m.w. of 70,000 and is readily susceptible to proteolysis generating smaller polypeptides that still retain antigenicity. Such an analysis also demonstrated multiple Sm-specific polypeptides, including species of 13,000 and 29,000 m.w. Because the immunoreactive species are protein in nature, the role of RNA for the detection of Sm and RNP by assay procedures such as immunodiffusion and counterimmunoelectrophoresis was examined. RNP, while still antigenically active, becomes insoluble after RNAse treatment; Sm remains largely soluble after such treatment. Both antigens can be reconstituted from their separated protein and RNA moieties with restoration of precipitin reactivity.

Assays for the Sm and RNP autoantigens: the requirement for RNA and influence of the tissue source

The disease systemic lupus erythematosus is characterized by antibodies directed against two nuclear antigens, designated Sm and RNP. The two antigens from any one tissue can be distinguished on the basis of the polypeptides recognized by anti-Sm and anti-RNP specific sera. Multiple polypeptides were associated with RNP isolated from rabbit thymus. To determine if these polypeptides were species-specific, a comparison was made of this antigen among different mammalian species. We report that the native RNP antigen has a m.w. of 70,000 and is readily susceptible to proteolysis generating smaller polypeptides that still retain antigenicity. Such an analysis also demonstrated multiple Sm-specific polypeptides, including species of 13,000 and 29,000 m.w. Because the immunoreactive species are protein in nature, the role of RNA for the detection of Sm and RNP by assay procedures such as immunodiffusion and counterimmunoelectrophoresis was examined. RNP, while still antigenically active, becomes insoluble after RNAse treatment; Sm remains largely soluble after such treatment. Both antigens can be reconstituted from their separated protein and RNA moieties with restoration of precipitin reactivity.

Identification of the immunogenically active components of the Sm and RNP antigens

The spectrum of cellular targets in the autoimmune diseases is both large and varied and includes among the nuclear components the so-called Sm and RNP antigens associated with systemic lupus erythematosus. The use of immunoaffinity chromatography with dual specificity for the Sm and RNP antigens has allowed for their substantial purification from rabbit thymus in parallel and in quantity. In lieu of a functional assay, the use of a counterimmunoelectrophoresis assay provided a sensitive and rapid means of monitoring the distribution of the two antigens during purification and ensured the isolation of complexes containing the components required for antigenicity. The resulting purified complex consisted of nine polypeptides having molecular weights of approximately 9000 to 44,000 and two small RNAs of similar size. However, limited proteolysis of the isolated complex suggested that most of these polypeptides were not actually required for antigenic activity. Unlike Sm in crude thymus extracts, purified Sm was RNase sensitive. Thus, one of the major diagnostic criteria used to distinguish Sm and RNP antigens in crude extracts was shown to be invalid for purified material, suggesting that both antigens from rabbit thymus are actually ribonucleoprotein complexes.

Prevention and treatment of endometrial disease in climacteric women receiving oestrogen therapy

The treatment regimens are described in 74 patients with endometrial disease among 850 climacteric women receiving oestrogen therapy. Cystic hyperplasia was associated with unopposed oestrogen therapy without progestagen. Two courses of 21 days of 5 mg norethisterone daily caused reversion to normal in all 57 cases of cystic hyperplasia and 6 of the 8 cases of atypical hyperplasia. 4 cases of endometrial carcinoma referred from elsewhere demonstrated the problems of inappropriate and unsupervised unopposed oestrogen therapy and the difficulty in distinguishing severe hyperplasia from malignancy. Cyclical low-dose oestrogen therapy with 7--13 days of progestagen does not seem to increase the risk of endometrial hyperplasia or carcinoma.

Zinc deficiency in total parenteral nutrition

A patient with multiple enterocutaneous fistulae who developed the skin manifestations of acrodermatitis enteropathica while on total parenteral nutrition is described. The value of monitoring the serum alkaline phosphatase to demonstrate zinc deficiency is shown. The skin manifestations responded rapidly to the re-introduction of zinc to the diet.

Enzymic assays for isomers of 2,6-diaminopimelic acid in walls of Bacillus cereus and Bacillus megaterium

An enzymic assay for individual isomers (meso-, LL- and DD-) of 2,6-diaminopimelate was developed. The enzyme 2,6-diaminopimelate decarboxylase specifically attacked meso-diaminopimelate and was used to measure this isomer manometrically. The meso- and LL-isomers were measured together manometrically in a coupled assay with diaminopimelate decarboxylase and diaminopimelate epimerase (which converts LL-diaminopimelate into meso-diaminopimelate). The DD-isomer was not attacked by either enzyme and was measured, as residual diaminopimelate after the coupled assay, by a colorimetric method, which was also used to measure total diaminopimelate before enzymic treatments. The coupled enzymes were also used to prepare pure DD-isomer from chemically synthesized diaminopimelate. A mixture of diaminopimelate isomers was present in walls of four strains of Bacillus megaterium [in each about 75% (w/w) meso-, 18% LL- and 7% DD-] and in walls of two strains of Bacillus cereus (about 85% meso-, 8% LL- and 7% DD-). One strain of B. cereus contained at least 95% meso-diaminopimelate, with only traces of LL- and DD-isomers. Peptidoglycan from Escherichia coli was assayed as containing at least 95% meso-isomer. The proportion of isomers in the wall of a strain of B. megaterium remained constant after growth in a variety of different media.

Use of auxotrophic mutants to isolate LL- or DD-isomers of 2,6-diaminopimelic acid

Pseudomonas aeruginosa PAC7 (a mutant deficient in diaminopimelate epimerase), excreted diaminopimelate (solely LL-isomer) after growth in a minimal medium plus lysine with succinate as carbon source. More diaminopimelate was excreted when bacteria were transferred at the end of the exponential phase of growth into fresh minimal medium without lysine but supplemented with pyrivate and additional (NH4)2SO4. The excreted LL-isomer was isolated from the culture filtrate by ion-exchange chromatography and purified by crystallization (1.7 g/9 1 culture). A diaminopimelate-requiring mutant of Bacillus megaterium NCIB7581 grew on LL- and/or meso-diaminopimelate but not on the DD-isomer. This mutant was used to isolate the DD-idomer from a mixture of synthetic LL- and DD-diaminopimelate. It was grown in a minimal medium containing glycerol as carbon source and LL- plus DD-diaminopimelate at a growth-limiting concentration (300 mg l-1); when growth stopped, the DD-diaminopimelate that remained in the culture was isolated and crystallized (1.0 g/II l culture).

The regulation of diaminopimelate decarboxylase activity in Escherichia coli strain w

Activity of diaminopimelate decarboxylase in Escherichia coli strain W, growing in an aerated fermenter, was only slightly (14%) repressed by 2 mM-lysine when approximately equimolar diaminopimelate was present in the medium. Lysine alone caused 78% repression. Diaminopimelate did not interfere with uptake of lysine by growing organisms. Organisms grown in medium containing diaminopimelate, without lysine, had a decarboxylase activity 24% higher than organisms from minimal medium. The extent of repression by pyridoxine (56% when added to minimal medium) was decreased (to 31%) when diaminopimelate was also present in the medium. A diaminopimelate-requiring mutant, with limited ability to take up diaminopimelate, formed almost three times less diaminopimelate decarboxylase than did a diaminopimelate-requiring second-stage mutant that had an increased rate of transport of this amino acid. The internal concentration of diaminopimelate thus probably regulates the activity of the decarboxylase by induction. Lysine might not directly repress the enzyme but might give an apparent repression by restricting the biosynthesis of diaminopimelate. This restriction is probably not caused only by inhibition or repression of aspartokinase. Lysine and threonine together, though not singly, almost completely inhibited aspartokinase in vitro but caused less apparent repression of diaminopimelate decarboxylase than did lysine alone. Lysine plus diaminopimelate strongly repressed the lysine-sensitive aspartokinase (85%) without much affecting diaminopimelate decarboxylase formation, and pyridoxine repressed the decarboxylase without affecting aspartokinase.

The nutritional requirements of methicillin-dependent and -resistant strains of Pediococcus cerevisiae

A new methicillin-dependent and -resistant substrain (called MRD) of Pediococcus cerevisiae was developed by serial passages followed by replica-plating. Other methicillin-resistant, but not -dependent, substrains were isolated after treatment of the same parent strain with a mutagen. A methicillin-independent partial revertant, still resistant to the drug, was isolated from the original methicillin-dependent and -resistant substrain (CRD) developed several years ago. The requirements of some of these strains for acetate, vitamins and amino acids were compared. All except the parent methicillin-sensitive strain required pantothenate for growth, but no other consistent differences were found. The parent, but not strain CRD, grew without lysine added to the medium, though 19 other amino acids were needed by each strain. Both of these strains fermented glucose to lactate (mainly the L-isomer) in the absence or presence of methicillin.