Ludwik Anigstein

Antibacterial activity of hydrolyzed red blood cells in vitro.

Summary Red blood cells of various animals were submitted to enzymatic hydrolysis in alkaline medium, the resulting products exhibiting in vitro marked antibacterial activities. The latter covered a relatively wide spectrum of most gram-positive and a few gram-negative organisms. The highest activity was displayed by hydrolysates of human and bovine hemoproteins. Hydrolyzed bovine hemoglobin powder likewise exhibited antibacterial properties. These antibacterial products are heat-resistant and water-soluble. Their optimum activity lies in the pH range of 7.0 to 8.0. It is assumed that the active principle of the crude substance is a peptide-amino acid complex. This complex proved to be nontoxic to guinea pigs and albino mice. Its relation to other antibiotics is discussed.

THE SUPPRESSION OF EXPERIMENTAL RICKETTSIAL INFECTIONS BY ANTIORGAN SERA IN THE PRESENCE OF TESTICULAR EXTRACT

It was through the effect of the tissue extracts on the course of infectious processes that the spreading factors were discovered (Duran-Reynals, 1928). I t is not surprising, therefore, that these substances, particularly their power to increase the permeability of the hosts tissue, became the object of great interest to the microbiologist. The establishment of the spreading factors (S. F.) among products of certain strains of bacteria (Duran-Reynals, 1933) was followed by the isolation of the invasive enzyme, hyaluronidase, from autolysates of pneurnococcus (Meyer, Dubos, and Smyth, 1936). These fundamental studies led to the establishment of the mucolytic elTFect of hyaluronidase on the ground substance of the connective tissue. Thus, not only was the basis for the concept of tissue permeability created, but a new light was thrown on the fluctuations in the degree of infectivity. An abundance of accumulated observations points to the enhancing effect of the invasive enzymes when added to bacterial or viral inocula in promoting the intensity of the infection (Duran-Reynals, 1942). Since various infectious agents must pass through the barrier of the ground substance, it is apparent that the rnucolytic enzymes present in or added to the system may decide the outcome of the invasion. Consequently, the skin and its state of permeability, which may be a constitutional factor, can determine the susceptibility to infection. Should the increased permeability prevail in larger groups of individuals, the condition may possibly assume an epidemiological importance. This applies particularly to infections in which, under natural conditions, the skin is the portal of entry. Representative in this regard are the arthropod-borne infections, whether protozoal, bacterial, rickettsial, or viral in nature. In these cases, the infective agent conveyed by the arthropod vector must penetrate through the dermal barrier of the host and reach the connective tissue for further propagation The successive phases of the infection will depend on the degree of invasiveness or virulence of the pathogenic agent (Duran-Reynals, 1942). As to the viruses and rickettsiae-typical cell invaders-their mechanism of invasion is still obscure. Apparently, they are not provided with spreading factors affecting the ground substance of the mesenchyme (Duran-Reynals, 1942). Recent investigations of Burnet (1948) and his school in Australia revealed the presence of an enzyme as an integral part of the influenza-virus surface. The substrate of the enzyme is a much present in the surface of erythrocytes and cells susceptible to infection. This rnucin is considered as a receptor provided with a specific adsorptive power and one which, if destroyed by the receptor destroying enzyme (RDE), renders the cells insus-

Reticulo-Endothelial Immune Serum (REIS). VI. Production of Potent Serum by Anamnestic Reaction.

Summary In the preparation of antiorgan sera the administration of small amounts of antigen (spleen and bone marrow) was found more effective than the rapid immunization of rabbits with massive antigen dosage. A single injection of the antigen 30-40 days after the last dose gives rise to an anamnestic response of the host and to a serum of higher potency. This can be evaluated by complement fixation titres and by the outgrowth of tissue explants exposed to the action of the “anamnestic” serum.

Effect of Sanguinin, an Antibacterial Agent from Blood,∗ on Streptococcal Infection in Mice

Summary and Conclusions The blood hydrolysate Sanguinin was tested in vivo in 268 albino mice accompanied by 221 untreated controls for its effectiveness against the beta-hemolytic Streptococcus zooepidemicus. Sanguinin solution (20 mg/ml) was inoculated subcutaneously (0.25 to 1.0 mg/mouse daily, usually for 4-6 days) either prior or after infection. Suppressive effect on the course of the infection was noted in all series of treated mice. A significant increase in survival time was noted in the pretreated series with an average survival percentage of 38.9 compared with 6.0 of the total of untreated controls. It does not appear that a direct correlation can be established between the survival rates and the intake of Sanguinin or the length of its administration, however, pretreatment seems to be of decisive value.