CELLULAR REACTIONS TO A DYE-PROTEIN WITH A CONCEPT OF THE MECHANISM OF ANTIBODY FORMATION

1. The use of an antigen which can be seen within cells demonstrates that one may stimulate the phagocytic cells either of the liver and spleen or of the tissues and lymph nodes to produce antibodies. 2. The appearance of antibodies in the serum correlates with the time when the dye-protein is no longer visible within the cells and with the phenomenon of a partial shedding of their surface films. 3. It is thus inferred that the cells of the reticulo-endothelial system normally produce globulin and that antibody globulin represents the synthesis of a new kind of protein under the influence of an antigen. 4. An antigen is a substance which can specifically modify the synthesis of the cytoplasm of the cells of the reticulo-endothelial system

CELLULAR REACTIONS TO TUBERCULO-PROTEINS COMPARED WITH THE REACTIONS TO TUBERCULO-LIPIDS

1. Tuberculo-protein in solution induces the formation of monocytes in the normal animal and tubercles of epithelioid cells in that which is tuberculous. 2. Freshly precipitated tuberculo-proteins from the culture media and from the bacilli induce a moderate formation of epithelioid cells in normal animals, and more in the tuberculous. 3. Insoluble forms of tuberculo-protein induce complex tubercular tissue in normal animals. This action is enhanced in the tuberculous

REACTIONS OF NORMAL AND TUBERCULOUS ANIMALS TO TUBERCULO-PROTEIN AND TUBERCULO-PHOSPHATIDE

Prior observations on the cellular reactions to tuberculo-phosphatide are confirmed and compared with reactions induced by this material in tuberculous animals. In the latter the response is accelerated and augmented and simulates the Koch phenomenon. Tuberculo-protein produces no macroscopic reaction in normal animals. The microscopic reaction of neutrophiles and monocytes regresses in less than a week. The same material in tuberculous animals causes a response characterized by more or less hemorrhage and necrosis, tissue degeneration, and infiltration of neutrophiles and monocytes. Late in the reaction there may be a few epithelioid cells and foreign body giant cells. Preparations of tuberculo-phosphatide which contain no tubercle bacilli, or only a few, induce the typical cellular response but do not induce hypersensitiveness to tuberculin. Repeated intradermal skin-test injections of tuberculo-protein MA-100 in normal guinea pigs may be followed by a mild hypersensitiveness to subsequent injections

NORMAL AND PATHOLOGICAL FRAGMENTATION OF RED BLOOD CELLS; THE PHAGOCYTOSIS OF THESE FRAGMENTS BY DESQUAMATED ENDOTHELIAL CELLS OF THE BLOOD STREAM; THE CORRELATION OF THE PEROXIDASE REACTION WITH PHAGOCYTOSIS IN MONONUCLEAR CELLS

1. There is constantly some breaking down of red cells in the circulation by fragmentation. 2. The fragments of red cells, as well as whole red cells, are phagocytized and destroyed by clasmatocytes or endothelial phagocytes. 3. When there is an increase in fragmentation in abnormal or pathological states, desquamated endothelial cells of the blood stream, as well as the clasmatocytes of the tissues, increase proportionately and take in these fragments. These cells are to be distinguished from eosinophilic leucocytes by the nature of their granules, by the type of motility of the cells, and by a negative peroxidase test. 4. The desquamated endothelial cells, clasmatocytes, in the circulating blood are positive to the peroxidase test only when they have taken in positive material. 5. The monocytes show marked variations of the oxidase reaction in different species and to different techniques. With the Sato and Sekiya technique most monocytes of human blood are positive, while most of them in rabbit blood are negative, but both positive and negative reactions are found in both human and rabbit blood

THE RELATION OF MONOCYTES AND CLASMATOCYTES TO EARLY INFECTION IN RABBITS WITH BOVINE TUBERCLE BACILLI

1. The early reaction to intravenous tubercular infection in the various organs of the rabbit reveals a pathognomonic response in the lungs within 24 hours; the specific response in the liver, spleen, lymph glands, and bone marrow, follows from the 6th to the 14th days. 2. The development and extent of the pathologic process has been analyzed in terms of the activity of monocytes and clasmatocytes. 3. The criteria for differentiating these mononuclear phagocytic cells into two strains have been analyzed and the technics discussed. 4. The clasmatocyte phagocytizes tubercle bacilli freely and fragments them, as it does all cellular and other debris. 5. The monocyte stimulated to metamorphose into the typical epithelioid and giant cell of the Langhans type retains the tubercle bacilli intact, with power to survive and multiply, over long periods of time. 6. The normal number of monocytes or the degree to which monoblasts may be stimulated to development and maturation, together with the activity of the clasmatocytes in destroying bacilli, in any particular region, would appear to be a function of the rapidity and extent of the local tubercular involvement

THE PRESENCE OF DESQUAMATED ENDOTHELIAL CELLS, THE SO CALLED CLASMATOCYTES, IN NORMAL MAMMALIAN BLOOD

1. There is a practically constant desquamation of endothelial cells into the circulating blood in rabbits and man. 2. These endothelial cells represent the entire range in size of endothelium from very small cells, possibly from capillaries, up to the type of the large Kupffer cell. 3. These desquamated cells can be discriminated from monocytes. 4. There are common morphological and functional characteristics among the following cells: the clasmatocytes from the specific endothelia, such as the cells from the sinuses of the liver, spleen, and bone marrow; the clasmatocytes of the diffuse connective tissues; and desquamated endothelial cells occurring in normal and pathological blood. 5. There are four strains of white cells in the normal circulating human and rabbit blood, granulocytes, lymphocytes, monocytes, and endothelial phagocytes

CELLULAR REACTIONS TO DEFATTED TUBERCLE BACILLI AND THEIR PRODUCTS

The cellular reactions to defatted tubercle bacilli are complex and like those to heat-killed whole tubercle bacilli. The firmly bound lipid, when removed from these organisms, is non-acid-fast; it contains an hydroxy acid which is acid-fast and a polysaccharide, which is not. This hydroxy acid gives rise to foreign body giant cells and the tissues eventually become infiltrated with eosinophiles. The polysaccharides, both from the defatted bacilli and from the unfilterable lipid, call neutrophiles from the blood stream. The reactions to the unfilterable lipid include those of both its constituents

THE CELLULAR REACTIONS TO LIPOID FRACTIONS FROM ACID-FAST BACILLI

1. A comparative study has been made of the cellular reactions induced by phosphatides from five strains of acid-fast bacilli. Each of these reactions is characterized principally by epithelioid cells and giant cells. 2. The phosphatides are first phagocytized by young connective tissue cells or monocytes. The lipoid is then dispersed into fine particles with the formation of classical epithelioid cells. 3. A comparison has been made of the reactions induced by heat-killed and defatted tubercle bacilli with those induced by tuberculophosphatide. 4. Further studies have been made to determine whether or not the phosphatide causes sensitization to tuberculin. It does not do so. 5. The life cycle of the epithelioid cell has been observed in all its stages

LOCAL PROGRESSION WITH SPONTANEOUS REGRESSION OF TUBERCULOSIS IN THE BONE MARROW OF RABBITS, CORRELATED WITH A TRANSITORY ANEMIA AND LEUCOPENIA AFTER INTRAVENOUS INOCULATION

In this series of rabbits it was found that the rabbits dying during the 1st month after an injection of I or 2 mg. of bovine tubercle bacilli show the same conditions: extreme tuberculosis of the lungs, acute splenic tumor with tuberculosis, involvement of the lymph glands, an occasional small tubercle in the liver and extensive tuberculosis of the bone marrow. The peripheral blood has shown a sharp fall in the platelet count, an anemia and a fall in the granulocytic strain of white cells, and these changes have been correlated with the condition of the bone marrow. There has also been a rise in monocytes and a fall in lymphocytes, to a reversal of the normal ratio. When the rabbits have survived the first acute phase of the disease longer than 3 to 4 weeks, there have been signs in the peripheral blood of a recovery of the bone marrow; the first indication of this has been an increase in platelets, then a rise in hemoglobin followed in 1 or 2 days by a rise in red cells and later a return of the three strains of granulocytes. The bone marrow has shown a rapid spontaneous disintegration of the epithelioid cells correlated with the appearance of increased evidence of acid-fast debris in clasmatocytes, especially clear in those that lie along the vessels. The animals that have survived into the 3rd month have all shown a hyperplastic phase of the healing marrow, both the red cells and all types of the granulocytes appearing in the peripheral blood in numbers above the normal. The epithelioid cells originally containing many bacilli all disappear from the marrow and the only sign left, possibly suggestive of the tuberculosis, is the acid-fast granules in the clasmatocytes. Finally, the marrow becomes entirely normal, giving the normal number of red cells and granulocytes to the blood. Thus, bone marrow in the rabbit has become involved in every instance with the injection of massive doses of viable bacilli. The findings at autopsy in those animals followed during the early reaction to infection confirm this directly and, since the curves of the cells in the peripheral blood of the more chronic animals were the same during the early stages of the disease as in those that died, the same conclusion seems justified from indirect inference for them. The method of healing has been a rapid disintegration of the epithelioid cells without caseation. The bone marrow heals itself entirely regardless of the progress of the disease elsewhere, so that one sees the remarkable condition of an animal recovering from the anemia and leucopenia while dying of tuberculosis elsewhere. The spleen also shows a tendency toward spontaneous healing. In the animals that have lived beyond 100 days there has been some gradual lessening of the diffuse distribution and extent of pulmonary lesions with the development of cavitation together with a marked involvement of the kidneys and lesions in the eyes

TUBERCULAR ALLERGY WITHOUT INFECTION

1. Guinea pigs can be rendered hypersensitive to tuberculo-protein by small, repeated, intradermal injections of active tuberculo-protein. 2. The addition of tuberculo-phosphatide to the protein speeds up the process of sensitization and enhances it so that the reactions become indurated and necrotic, closely simulating those of the disease. 3. Active tuberculo-proteins induce a new formation of monocytes and some epithelioid cells. The addition of phosphatide to the protein brings about a massive formation of epithelioid cells. 4. With the increased cellular reaction to the mixed injections may be correlated the increase in the speed and intensity of the sensitization. 5. The intradermal route is the best for these sensitizations, probably because it provides the greatest dose per cell of the sensitizing agent. 6. The degree of sensitization artificially obtainable by the synergistic action of tuberculo-phosphatide and tuberculo-protein is quite comparable to the degree of sensitization naturally occurring in tuberculous animals; moreover, this degree of sensitization may be induced with amounts of the materials from the bacilli which could conceivably be present in the tissues of an infected host