[Lymphocyte reaction to streptococcal antigens in patients with normal and elevated antistreptolysin titer]

[Humoral and cell-mediated immune reactions in chronic posttraumatic osteomyelitis (author's transl)]

The humoral and cell mediated immune response was investigated in 90 patients suffering from chronic posttraumatic osteomyelitis. In 10-20% of the patients the serum IgG and IgM was increased, in 5-10% the levels were decreased. The values were compared with those of a control group of 35 normal healthy volunteers. Of 55 patients with staphylococcal infection only 25 had a positive antistaphylolysin titer. Eleven out of 25 patients with staphylococcal osteomyelitis showed a positive in vitro lymphocyte transformation after stimulation with alpha-staphylolysin (mean transformation rate 5.4 equal to or less than 0.9). The phytohemagglutinin and the pokeweed-mitogen response were normal. A comparison of the immunological reactivity of the patients and the clinical severity of the disease showed that patients with established delayed-type hypersensitivity phenomena suffered a significantly worse clinical course of the disease.

Transformation of lymphocytes in patients with certain bacterial infections

The state of cell-mediated immunity was measured by the morphological method of lymphocyte transformation with and without PHA, in a group of 56 patients with bacterial infections and in a group of healthy controls. The patients were divided into three subgroups according to the aetiology: 1. Patients with Gram-positive infections, 2. Patients with Gram-negative infections, and 3. mixed infections. The transformation values with PHA were significantly (t-test) higher in the Gram-positive subgroups than in the control group. Transformation in cultures stimulated by PHA was much higher in the subgroup of patients with Gram-positive aetiology; the difference between the values in the Gram-negative and in the Gram-positive subgroups was also significant. A decrease of transformation value below 50% was observed in 6 out of 18 patients with Gram-negative aetiology, whereas in the Gram-positive group it was noted in only 2 out of 21 patients.

[Biological activity of bacterial peptidoglycan (mucopeptide) (author's transl)]

A brief survey on the ultrastructure, the chemical composition and the immunological properties of bacterial cell wall peptidoglycan (mucopeptide) is presented. This paper deals with the various recently discovered biological activities of peptidoglycan. These could be divided into three different groups, namely: 1. Endotoxin-like properties: pyrogenicity, induction of the local Shwartzman reaction, increase in non-specific resistance to bacterial infection, release of 5-hydroxytryptamine from rabbit platelets, complement activation,gelation of amebocyte lysate. 2. Inflammatory reactions of skin and internal organs, aggressin activity (virulence factor), inhibition of phagocytosis of bacteria by granulocytes and macrophages, inhibition of growth of cell cultures, cytotoxity to granulocytes and macrophages. 3. Potentiation of humoral and cellular immune responses (adjuvant), enhancement of tumor defense in experimental animals. The potential mechanisms of action of peptidoglycan are discussed and attention is focused on the implications of the various peptidoglycan activities for medicine.