Charles A. Evans

MECHANISMS OF TUMOR HOMOGRAFT REJECTION: THE BEHAVIOR OF SARCOMA I ASCITES TUMOR IN THE A/JAX AND THE C57BL/6K MOUSE*

The respective roles that classical humoral antibodies and hypothetical “cellassociated” antibodies may play in tumor homograft rejection and the mechanisms by which they act remain major unsolved problems in homograft immunity. Whereas classical humoral antibodies to tumor homografts are commonly produced, their participation in tumor rejection has been clearly demonstrated only in a limited number of tumor-host combinations. Tumors derived from cells of the lymphoid series appear to be particularly susceptible to in vivo destruction by humoral antibody. Excellent discussions of the evidence bearing on the problem of the mechanisms of tumor homograft rejection have been presented recently by Gorer,’ Amos: and Snell and co-~orkers .~ The purpose of the present investigation is to gain further information about the mechanisms by which cell-associated antibody factor of immune host cells may accomplish the destruction of tumor cell homografts. The system, Sarcoma I (Sa I) in the C57BL/6K mouse, was chosen because it is one in which homograft rejection appears to depend solely on cell-associated antibody. Indeed, in this system classical humoral antibody exerts a suppressive rather than an augmentative effect on tumor rejection and induces an “immunological enhancement” of tumor growth rather than i m m ~ n i t y . ~ Sarcoma I originated in 1947 in a mouse of the Strong A strain that had been treated with dibenzanthracene. The tumor grows progressively in the A/ Jax subline of the Strong A mouse and kills 100 per cent of the animals. In contrast, mice of the resistant C57BL/6K strain, given a standard dose of 30 million ascites tumor cells by the intraperitoneal route, reject the tumor in essentially 100 per cent of the cases. The tumor shows unrestricted growth in the animals until the 6th or 7th day, when rejection begins. Rejection is largely completed by the 8th day, and the animals remain immune to rechallenge for weeks thereafter. Since our preliminary attempts failed to demonstrate that Sa I cells are destroyed by reaction in vitru with immune cells, attention was centered on in vizw studies of interaction between immune host cells and tumor cells. If the rejection of Sa I by the C57BL/6K mouse results from contact of immune

Growth of neurotropic viruses in extraneural tissues IV. Poliomyelitis virus in human testicular tissue in vitro.

Summary The Lansing and Hof. strains of poliomyelitis virus multiplied extensively in tissue cultures of testes from men 57 to 93 years old, most of whom had carcinoma of the prostate gland. Lansing virus was carried through 8 successive tissue cultures and Hof. virus was carried through 7 cultures. Several less extensive series were completed with each virus. The amount of Hof. virus in these tissue cultures per milligram of tissue was approximately the same as was obtained in infected monkey spinal cords.

Suppressive effects of pyrilamine maleate and d-lysergic acid diethylamide (LSD-25) on early corneal lesions produced in vitro by Newcastle disease virus (NDV) and compound 4880

Abstract Injection of 108 plaque-forming units (PFU) of Newcastle disease virus (NDV) into the anterior chamber of the rabbit eye causes a “toxic” reaction characterized by edema of the cornea with extensive damage of corneal endothelium. No evidence of increase of infectious virus is associated with the above reaction. Within 1 hour after injection of virus, characteristic lesions called cndothelial rosettes were seen by staining the corneal endothelium with silver nitrate. Endothelial rosettes were also produced by 1 10 or 1 100 the amount of virus required to produce a macroscopically visible toxic reaction. The number of rosettes was related to the amount of virus inoculated. The same toxic effect was obtained by injection of 25 μg of compound 48 80 , a substance with various pharmacologic effects including release of histamine. These lesions can be induced by mechanical trauma and are a relatively nonspecific manifestation of damage. The number of rosettes produced by virus in vitro was greatly reduced by pretreatment with receptor-destroying enzyme, or by inactivating the virus with specific immune serum, or by heat. Pretreatment of the eye by injection of 100 μg of an antihistamine, pyrilamine maleate, or 100 μg of the antiserotonin agent, d-lysergic acid diethylamide (LSD), moderately reduced the number of rosettes produced by either virus or compound 48 80 . One hundred micrograms of each of the two antagonists when used together markedly reduced the number of rosettes produced by either virus or 48 80 .

Rabbit kidney vacuolating virus: Extraction of infectious DNA ☆

Abstract Deoxyribonucleic acid (DNA) preparations capable of exhibiting cytopathic effects (CPE) on primary and secondary cell cultures of rabbit kidneys were obtained from the rabbit kidney vacuolating (RKV) virus-infected tissue cultures by a phenolic extraction procedure. The active factor in the preparations was concluded to be DNA in nature by the following criteria: The CPE-producing capacity of the nucleic acid (NA) preparation could be completely abolished by its exposure to deoxyribonuclease (0.5 μg/ml) but not with ribonuclease (50 μg/ml) or with trypsin (100 μg/ml). Antiserum, sufficient to neutralize 104 tissue culture infectious dose50 (TCID50) of RKV, did not block the appearance of CPE in tissue cultures exposed to NA preparations. The infectivity of the RKV-DNA was resistant to treatment with 1 M NaOH and resisted boiling at 100 ° for 60 minutes.

Comparative Study of Deoxyribonucleic Acid Homology and Physiological Characteristics of Strains of Peptococcus saccharolyticus

Polynucleotide sequence relationships among strains of Peptococcus saccharolyticus were assessed by analysis of deoxyribonucleic acid-deoxyribonucleic acid homo and heteroduplexes with endonuclease S1. The results showed that P. saccharolyticus strains isolated from different subjects form a very tight group, with deoxyribonucleic acid homology levels ranging between 93 and 100%. Physiological tests of 23 strains included 30 different substrates. Results were remarkably uniform. All 23 strains grew better anaerobically with added H2 and CO2 than aerobically. However, colony size was greater on blood agar but not Trypticase soy (BBL Microbiology Systems, Cockeysville, Md.)-yeast extract agar with an atmosphere of 4% O2 with added H2 and CO2 than with anaerobic incubation. The data suggest that these strains are sufficiently closely related to justify their inclusion in a single discrete species, but their appropriate generic classification remains to be resolved.

Cultivation of Type 2 Dengue Virus in Rhesus Kidney Tissue Culture.

Sumary and conclusions Mouse-passaged type 2 dengue virus of the New Guinea C strain was cultivated in trypsinized rhesus kidney tissue cultures grown directly on glass surfaces and incubated in the stationary state at 35°C virus was maintained in this system of tissue culture through 18 passages during 176 days. Culture fluid from the 18th passage representing a 10-41.5 dilution of the original infected mouse brain was infective for mice. 2) The infected culture cells exhibited characteristic degeneration indistinguishable from that associated with infection of tissue cultures with type 1 dengue virus. Infectivity of the virus was neutralized by specific antiserum as indicated by the fact that the degeneration was suppressed completely by homologous immune rabbit serum, but not by heterologous serum. It appeared that the cellular degeneration produced by type 2 virus mixed with anti-type 1 serum was a little milder than that produced by the same virus mixed with the control non-immune serum. Although further studies are necessary to clarify the antigenic relationships of type 1 and type 2 dengue viruses, it is possible that the reduced degeneration was due to a partial neutralization by heterologous antibody.

Hypothermia in Mice Due to Influenza Virus Infection.

Summary and Conclusions 1. Hypothermia rather than fever was the characteristic thermal response of mice to intranasal inoculation of the PR8 strain of type A influenza virus. 2. Mice showed marked hypothermia with fatal termination in response to inoculation of large amounts, e.g., 1,000 or more infectious doses (ID50), of 2 sublines of the virus, one adapted to embryonated eggs and the other to mice. 3. Inoculation of mice with a small amount of virus, e.g., one to two ID50, did not cause hypothermia. In mice inoculated with about 2 ID50 of egg-line virus. the maximum level of virus in the lungs was lower than in mice inoculated with larger amounts of virus, and pulmonary lesions were present but failed to reach the level of 50% total lung-lesion score. 4. In mice inoculated with a moderate amount of egg-line virus. e.g., about 200 ID50, the maximum virus level in the lungs was reached 3 to 4 days before the occurrence of hypothermia. Time of occurrence and degree of hypothermia appeared to be closely related to the extent of pulmonary lesions. 5. The mouse-passaged virus caused more rapid development of hypothermia than the egg-line virus. 6. It is concluded that hypothermia is related to the extent of pulmonary lesion rather than to the extent of virus increase per se.

Stimulation of the Growth of Cutaneous Strains of Peptococcus saccharolyticus by Iron, Haematin and Blood

The growth of nine strains of Peptococcus saccharolyticus was assessed quantitatively by culture Trypticase Soy/yeast extract/Tween 80 agar (TSY-TW) with and without supplementation with iron or haematin and on blood agar, in aerobic, reduced 02 (3% O2 with 8% CO2, 8% H2 and 81% N2) and anaerobic atmospheres. All strains grew better anaerobically and under reduced O2 conditions than aerobically on supplemented or unsupplemented TSY-TW. Supplementation of TSY-TW with iron or haematin resulted in an average 4.4-fold increase in bacterial count in a reduced O2 atmosphere and an average 4.2-fold increase under anaerobic conditions. Under aerobic conditions the increase in count ranged from O to greater than 5000-fold, as some strains failed to grow on unsupplemented TSY-TW but responded well to the supplements of iron or haematin. The highest bacterial counts were obtained on Columbia blood agar incubated anaerobically. However, P. saccharolyticus failed to grow aerobically on plain or heated Columbia blood agar with or without supplements. TSY-TW blood agar supported the growth of the one strain tested under all three atmospheric conditions. The type strain (ATCC 14953) differed from all others in its failure to grow aerobically or in a reduced O2 atmosphere on supplement or unsupplemented media. Colony size varied greatly on different media, in different atmospheres and from strain to strain, being greatest in a reduced O2 atmosphere on Columbia blood agar. There was no correlation between the viable bacterial count and colony size.

Growth of Neurotropic Viruses in Extraneural Tissues. I. MM Virus in the Feet of Hamsters

Summary and Conclusion After inoculation into the pad of the hind foot of a hamster, MM virus increases in amount in the local tissue. Subsequent increases in virus in the blood and viscera are in turn followed by appearance of the virus in the central nervous system. It appears certain that the virus grows in the foot. Whether the growth occurs in subcutaneous tissue, muscles, or nerve endings was not determined in these experiments.

Local increase of poliomyelitis virus in healing wound tissue of cynomolgus monkeys.

Conclusions 1. Pieces of skin 1 cm square were removed from the backs of 2 mature male cynomolgus monkeys. When the sites of excision were 3 to 6 days old, poliomyelitis virus of the Saukett strain was inoculated into the lesions. In the 6 lesions, 3 days old at the time of inoculation, the concentration of virus was minimal at 1 day. Subsequent increase of virus occurred in the case of 4 of these lesions. 2. The amount of virus in the exudate from lesions 5 and 6 days old at the time of inoculation was close to a maximal level at 1 day. At 5 days virus was present in approximately maximal concentration in 11 of the 12 lesions. Virus was present in 7 of the 8 lesions tested for virus one week after inoculation. Extensive healing of wounds had occurred by this time.