Resume

Le systeme bactericide de la properdine comprend 6 facteurs: la properdine - les 4 constituants du complement et des ions de magnesium. La properdine humaine est une euglobuline de poids moleculaire tres eleve et ne represente pas plus de 0.03 pour cent des proteines seriques totales. Elle peut etre absorbee sur un polysaccharide insoluble prepare de levure et enrichie 3000 a 7000 fois.



Le taux sanguin de properdine est sujet a des variations considerables sous l'influence de diverses conditions experimentales et pathologiques: une irradiation totale diminue le taux de properdine; c'est le cas egalement lorsque des chiens sont atteints de choc hemorrhagique.



Une injection intraveineuse de zymosan reduit considerablement la teneur de properdine. Elle reapparait rapidement et atteint apres quelques jours des valeurs 2 a 3 fois superieures aux taux normaux.



En general l'activite bactericide des serums est parallele aux titres de properdine.



La properdine differe d'un anticorps en ce qu'elle intervient immediaternem en cas d'invasions bacterielles et en ce que son action n'est pas specifique.



Zusammenfassung

Das Properdinsystem umfaβt 6 Faktoren: Properdin (ein hoch-molekulares Euglobulin), die vier Komponenten des Komplements und Magnesiumionen. Beim Menschen wird der Properdingehalt auf hochstens 0.03 % des Gesamtserumeiweises geschatzt. Properdin 1ast sich durch Adsorption an ein unlosliches Polysaccharid der Hefe 3000–7000 fach anreichern.



Der Properdintiter des Serums ist starken Schwankungen unter-worfen: Ganzkorperbestrahlung und hamorrhagischer Schock fuhren zu einem signifikanten Abfall des Properdinspiegels.



Intravenose Verabreichung von Zymosan fuhrt zu einer Verminderung des Properdins, das sich aber rasch nachbildet und nach wenigen Tagen auf das 2–3 fache des Normalwertes ansteigt. Im allgemeinen geht die Bakterizidie des Serums dem Properdingehalt parallel.



Properdin unterscheidet sich von einem Antikorper durch das unmittelbare Einsetzen seiner Wirkung nach bakteriellen Infektionen und dadurch, das seine Wirkung nicht spezifisch ist.

The Properdin System

1. Das Prinzip der Bestimmung von Komplement und seiner Einzelkomponenten wird geschildert und gezeigt, das lyophil getrocknete und standardiserte R-Seren zu ihrer Bestimmung verwendet werden konnen. 2. Fur die Properdinbestimmung erwiesen sich lyophilisierte, humane RP-Seren und R3-Seren vom Meerschweinchen als besonders gut geeignet. 3. In Abweichung der Pillemerschen Methode wird vorgeschlagen, bei der Properdin-Bestimmung die Zunahme an C′3-Aktivitat durch das zu testende Serum mit zu berucksichtigen. Es wird eingehend begrundet, warum das Auserachtlassen dieser Zunahme zu erheblichen Fehlern fuhren kann. 4. Auserde m wird eine auf die beschriebene Methode abgestimmte neuartige Berechnungsweise der Properdineinheiten vorgeschlagen. Als eine Einheit Properdin wird die Menge definiert, die eine Abnahme von 50% der C′3-Aktivitat in 1 ml Testserum bei Gegenwart von 0,25 ml RP-Serum im Testansatz bewirkt. 5. In vergleichenden Untersuchungen wird festgestellt, das Properdin in menschlichen Seren auch ohne vorheriges hochtouriges Zentrifugieren bestimmt werden kann.

Über die Bestimmung von Properdin und Komplementfaktoren

High-mol.-wt levan injected locally inhibits the growth of Lewis lung carcinoma in C57BL mice. The inhibition is dependent on the number of tumour cells injected and on the dose of levan. The inhibition decreases tumour incidence and size as well as prolonging survival. The polysaccharide is most effective when injected daily beginning on the day of tumour-cell inoculation. Treatment begun on later dates is less effective. Treatment begun one day before tumour-cell inoculation enhances tumour growth. Histological studies showed that levan induces an intense polymorphonuclear (PMN) reaction followed by accumulation of vacuolated, levan-laden macrophages. Both PMN and activated macrophages seemed to have an inhibitory effect upon the growth of the tumour. The effector role of PMN was not explained by the histological study. Tumour cells in close contact with levan-laden macrophages appeared mostly necrotic. Administration of levan begun one day before tumour-cell inoculation produced a similar reaction, but the infiltrating cells did not appear to approach and damage the tumour cells.

The role of macrophages and polymorphs in the levan-induced inhibition of Lewis lung carcinoma in C57BL mice.

AKR lymphoma cells derived from spontaneous tumors were serially transplanted at identical inocula. The degree of malignancy and sensitivity to the polysaccharide levan and methotrexate were tested at each transfer by assessing the lag of development of primary and distant tumors and survival of mice. A progressive increase in malignancy, accompanied by a loss of sensitivity to levan, were observed following serial passage of the lymphoma. Sensitivity to methotrexate was not affected. It is reasoned that, since serial passages permit a longer exposure of the tumor cells to selective forces of the internal milieu of the organism, better reflecting the situation in a long-life span animal, spontaneous and serial-passage tumors could serve as models for cancer therapy in humans.

https://cancerres.aacrjournals.org/content/canres/44/5/1981.full.pdf

Serial Passage of Tumors in Mice in the Study of Tumor Progression and Testing of Antineoplastic Drugs

Activities of bacterial levans and of lipopolysaccharides in the processes of inflammation and infection.

Infection-promoting activity of levan and dextran as a function of degree of polymerization.

Promotion of peritoneal infection by intravenous levan.

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Infection-promoting activity of levan and dextran as a function of degree of polymerization.

Promotion of peritoneal infection by intravenous levan.