William A. Sodeman

The lymphatic pathology of Brugia pahangi in the Mongolian jird.

We studied the sequence of histopathologic changes associated with Brugia pahangi (Nematoda: Filarioidea) infections in lymphatic vessels in the spermatic cord of the Mongolian jird (gerbil), Meriones unguiculatus. Intravascular granulomas caused mainly by disintegrating worms were seen in 67% of jirds necropsied on, or after, 35 days postinoculation, whereas none of 20 jirds examined before this day showed dying larvae. These granulomas usually evolved without vascular occlusion. Other granulomatous foci, often with a thrombuslike core, sometimes harbored microfilariae or microfilarialike materials. The perilymphatic cellular infiltrate consisted mostly of eosinophils, lymphocytes, and plasma cells. Large numbers of eosinophils were seen in the early weeks, but later declined, while lymphocytes increased to become the predominant cell in old infections. Irregular fibrosis of some valves and portions of the lymphatic walls were seen as early as the 2nd wk postinoculation. Lymphatic changes in the jird are similar to those described in other hosts infected with filariae, but remained moderate. Living worms appeared to be the stimulus for many observed changes. Most pathologic alterations were well established by 3 or 4 mo and showed little qualitative change during the remaining 4 mo of the study.

Disk electrophoresis of Plasmodium berghei.

A method of analytic separation of soluble proteins in aqueous extracts of Plasmodium berghei is described. Extracts are prepared by sonication of suspensions of whole washed parasites obtained by saponin lysis of infected rat red cells. Separation of the extracts into reproducible electrophoretic patterns is carried out by zone electrophoresis on polyacrylamide gel. Extracts prepared in this manner contain a heterogeneous mixture of soluble protein constituents of both host and parasite origin. A minimum of 15 parasite proteins and an additional minimum of six proteins of host origin have been identified. This paper presents an analytic separation of water soluble proteins of Plasmodium berghei by the technique of disk electrophoresis. Electrophoresis is carried out in an acrylamide gel matrix of defined pore size permitting separation of components simultaneously by differences in charge and in size and shape. Application of this method to extracts of P. berghei has provided confirmation and extension of reported findings by agar immunoelectrophoretic methods that such extracts are a complex mixture of proteins (Zuckerman, 1964; Sherman, 1964).

Primary malarial thrombocytopenia in the rhesus monkey

Abstract In 3 intact and 2 splenectomized monkeys infected with Plasmodium cynomolgi a significant thrombocytopenia was observed. Platelet counts were at their lowest point at about the time of maximum parasitaemia but returned to normal in the face of continuing parasitaemia. This syndrome appears to have direct relation to the malaria infection and has been termed primary malarial thrombocytopenia.

Infectivity of jird-passaged and dog-passaged strains of Brugia pahangi (Nematoda: Filarioidea).

The mean intensity was high (x = 4.1) in snails of Group 6; their organs were in different states: the State P was observed in 17 organs, the State R in seven organs, and the State S in the last nine organs. Studies on the geographic strain of the parasite (Groups 1, 7, and 8; data not shown) revealed that in snails of Groups 1 and 7, the results were identical. In contrast, the mean intensity in snails of Group 8 was higher (x = 2.3) and 34 organs were in State N, 17 organs in State R. Results of effects of the number of miracidia for a single exposure (Groups 1 and 9-12) are shown in Figure 1C, D. The mean intensity of the amoebocytic reaction steadily increased from Group 1 to Group 12 (x = from 1.15 in Group 1 to 4.5 in Group 12). In Groups 1, 9, and 10, the organs were in States N or R; in Groups 11 and 12, 12 organs were in State P, 20 organs in State R, and nine organs in State S. The effects of the number of monomiracidial exposures (Groups 1 and 13-15) are shown in Figure IE, F. The mean intensity of the cellular reaction increased in these snails in the same proportion as the number of miracidia (x from 1.15 in Group 1 to 3.9 in Group he mean intensity was high (x = 4.1) in snails 5). The snails of Groups 1 and 13 have organs with States N or R. In Group 14, the organs are in States N, P, or R (10, 2, and 19, respectively); in Group 15, the organs are in States P, R, or S (7, 13, and 2 organs, respectively). These experiments have shown that amoebocyte-producing organs of L. truncatula exist in several identifiably different states of activity. Furthermore the state of a particular organ was influenced, at least in part, by the prior exposure of the snail to miracidia of F. hepatica. When the cellular reaction to the parasite was of low or moderate intensity, the amoebocyte-producing organs were in States N or R. When the intensity of the cellular reaction was higher, the organs were either persistently producing amoebocytes (State P), or were drained of their amoebocytes (State S). It would be of interest to know why the amoebocytic organ shows either of these unusual morphological states in the case of a generalized amoebocytic reaction of high intensity. Further studies using autoradiography will be conducted to determine the participation of the amoebocyte-producing organ in the development of the generalized amoebocytic reaction. ils of roups 1 and 13 have organs