SULFHYDRYL AND DISULFIDE GROUPS OF PROTEINS : II. THE RELATION BETWEEN NUMBER OFSH AND S-S GROUPS AND QUANTITY OF INSOLUBLE PROTEIN IN DENATURATION AND IN REVERSAL OF DENATURATION.

1. In native egg albumin no SH groups are detectable, whereas in completely coagulated albumin as many groups are detectable as are found in the hydrolyzed protein. In egg albumin partially coagulated by heat the soluble fraction contains no detectable groups, and the insoluble fraction contains the number found after hydrolysis.

IMMUNOLOGICAL AND CHEMICAL INVESTIGATIONS OF VACCINE VIRUS : III. RESPONSE OF RABBITS TO INACTIVE ELEMENTARY BODIES OF VACCINIA AND TO VIRUS-FREE EXTRACTS OF VACCINE VIRUS.

Humoral antibodies and a certain degree of resistance to infection with vaccinia, probably not enduring, are produced in rabbits by the repeated injections of inactive formolized (0.3 per cent) elementary bodies of vaccinia and virus-free filtrates of dermal vaccine virus. Single injections of large amounts of elementary bodies are not as effective as similar amounts administered in small repeated doses.

CUTANEOUS REACTIVITY OF IMMUNE AND HYPERSENSITIVE RABBITS TO INTRADERMAL INJECTIONS OF HOMOLOGOUS INDIFFERENT STREPTOCOCCUS AND ITS FRACTIONS.

Rabbits were immunized intravenously with intact indifferent streptococci, with homologous P fraction, and with an emulsion of mechanically ground cocci; others were sensitized by intravenous injection of the intact microorganisms. Their serologic and dermal reactions to these materials and to the homologous S fraction were compared with those of normal animals. The dissociation, in certain instances, between circulating antibody and dermal reactivity was noteworthy.

JENNERIAN PROPHYLAXIS BY MEANS OF INTRADERMAL INJECTIONS OF CULTURE VACCINE VIRUS.

The second revived strain of culture vaccine virus has been propagated through 130 culture passages during a period of 3 years. It seems to be adapted to in vitro cultivation and still has an intradermal titer (rabbits) of 1 to 100,000 or 1 to 1,000,000. Intradermal inoculations in human beings of 0.

IMMUNOLOGICAL STUDIES WITH THE VIRUS OF INFLUENZA.

Following infection with the virus of influenza, both ferrets and mice develop a state of active immunity to reinfection. The serum of these animals contains neutralizing antibodies, as evidenced by the capacity of the serum to confer passive protection to mice against infection with the P.R.

LIPOIDS AND IMMUNOLOGICAL REACTIONS : I. THE RELATION OF PHOSPHOLIPINS TO THE TYPE-SPECIFIC REACTIONS OF ANTIPNEUMOCOCCUS HORSE AND RABBIT SERA.

It has been demonstrated that the removal of lipoids from Type I antipneumococcus horse serum causes a loss of the visible phenomena of type specific agglutination and precipitation, and in the case of rabbit serum a marked reduction in these properties. Initial activity of the type specific antibody can be restored to extracted immune horse serum by the addition of lecithin, and to rabbit serum by the addition of cephalin. The significance of these observations in respect to the relation of phospholipins to the type specific reactions of antipneumococcus serum is discussed.

RIFT VALLEY FEVER : A REPORT OF THREE CASES OF LABORATORY INFECTION AND THE EXPERIMENTAL TRANSMISSION OF THE DISEASE TO FERRETS.

Three cases of Rift Valley fever in human individuals are reported. The virus was recovered from the respiratory tract of the patients and was transmitted to ferrets by the intranasal route. The experimental disease so produced in ferrets is characterized by fever, marked pulmonary lesions, and hemorrhagic phenomena.

THE PROTECTIVE ACTION OF TYPE I ANTIPNEUMOCOCCUS SERUM IN MICE : III. THE SIGNIFICANCE OF CERTAIN HOST FACTORS.

The power of specific antipneumococcus serum to protect mice against infection with Type I Pneumococcus has been studied with reference to the capacity of the animal to utilize the specific antibodies. With a single strain of mice it was found that smaller animals and those with large numbers of white cells in the peritoneal cavity are much better able to utilize the passively conferred immune principles. These two intrinsic factors were resolved into a single element; namely, the number of monocytes in the peritoneal cavity at the time of injection of culture and serum.

THE PROTECTIVE ACTION OF TYPE I ANTIPNEUMOCOCCUS SERUM IN MICE : II. THE COURSE OF THE INFECTIOUS PROCESS.

Observations are reported which concern the nature of the infectious process resulting from the intraperitoneal injection of mice with virulent pneumococci. The course of the infection has been figuratively reconstructed on the basis of the following data: The rate of bacterial multiplication, the numbers of cells present in the peritoneal cavity, the character of these cells at various stages, and the rate of phagocytosis. The significant alterations in this infectious process brought about by the administration of type specific immune serum are described, and the general significance of the findings discussed with reference to the functions of the immune serum and the rôle of phagocytes in protection.

THE PROTECTIVE ACTION OF TYPE I ANTIPNEUMOCOCCUS SERUM IN MICE : I. THE QUANTITATIVE ASPECTS OF THE MOUSE PROTECTION TEST.

The mouse protection test for the evaluation of type specific antipneumococcus serum has been studied with reference to the quantitative relationships between the amount of antibody and the number of injected bacteria. By varying both these factors through wide limits certain definite characteristics of the protection test have been defined. These are the Schwellenwert, the prozone, and the limiting titer zone.

IMMUNOLOGICAL AND CHEMICAL INVESTIGATIONS OF VACCINE VIRUS : II. CHEMICAL ANALYSIS OF ELEMENTARY BODIES OF VACCINIA.

Washed elementary bodies obtained from dermal vaccine virus contain ash, carbohydrate, fat, and nitrogen a part of which is undoubtedly in the form of protein. These components are similar to those found in bacteria and other substances of protoplasmic origin.

THE USE OF GRADED COLLODION MEMBRANES FOR THE CONCENTRATION OF A BACTERIAL ENZYME CAPABLE OF DECOMPOSING THE CAPSULAR POLYSACCHARIDE OF TYPE III PNEUMOCOCCUS.

1. The enzyme which decomposes the capsular polysaccharide of Type III Pneumococcus is associated with a protein which under optimal conditions of filtration passes through membranes with an average pore size of 10.6 mmicro but is held back by pores having a diameter of 8.

THE PURIFICATION OF THE ANTIBODIES IN TYPE I ANTI-PNEUMOCOCCUS SERUM, AND THE CHEMICAL NATURE OF THE TYPE-SPECIFIC PRECIPITIN REACTION.

1. Methods for the concentration of Type I pneumococcus antibody have been outlined. 2.

IMMUNOLOGICAL AND CHEMICAL INVESTIGATIONS OF VACCINE VIRUS : I. PREPARATION OF ELEMENTARY BODIES OF VACCINIA.

By means of differential centrifugation in the horizontal and angle centrifuges it is possible to obtain appreciable quantities of relatively pure elementary bodies of vaccinia. Such preparations of elementary bodies exhibit an extremely high titer of vaccine virus. The elementary bodies are specifically agglutinated by serum from rabbits immunized by means of injections of bacteria-free vaccine virus.

ENCEPHALOMYELITIS ACCOMPANIED BY MYELIN DESTRUCTION EXPERIMENTALLY PRODUCED IN MONKEYS.

The repeated intramuscular injections of aqueous emulsions and alcohol-ether extracts of sterile normal rabbit brains in some manner produced pathological changes accompanied by myelin destruction in the brains of 7 of 8 monkeys (Macacus rhesus). Eight, control monkeys remained well. Cultures from the involved brains remained sterile, and no transmissible agent was demonstrated by means of intracerebral inoculations of emulsions of bits of the brains into monkeys, rabbits, guinea pigs, and white mice.