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PubMed1999

The traffic of resting lymphocytes through delayed hypersensitivity and chronic inflammatory lesions: a dynamic equilibrium.

This essay is designed as a partial summary of the work of several students and colleagues from our laboratory. For the most part the experimental data have been published and this seminar represents an attempt to summarize, integrate and speculate on this work. In some situations the speculation is rather unrestrained and it is hoped that it will provoke discussion, controversy and better future experiments. Reference is made to the original articles and to recent reviews. In addition, since we have had the advantage of reading the other contributions to this volume, there is considerable reference to other chapters. We and others have argued in other publications that it is imperative to understand the normal physiological traffic of lymphocytes before one can adequately interpret data describing lymphocyte migration through pathological tissues. It has been useful to compare data derived from traffic through lymph nodes because there is considerable information on the individual lymph node with respect to blood-lymphocyte delivery and blood flow, prenodal input via peripheral lymphatics and, particularly in sheep, in the numbers and phenotypic analysis of the lymphocytes exiting lymph nodes in postnodal or efferent lymph (see Young, this volume). We consider the terms prenodal for afferent and post-nodal for efferent to be synonomous. In this volume, a significant contribution has been made by Cahill et al which describes the astonishing degree of lymphocyte traffic which occurs in fetal life prior to antigenic challenge. At the other extreme, in disease states, there is often profound activation of lymphocytes. This is most apparent in viral infections like HIV and SIV (Rosenberg et al, this volume) and also in the various models of diseases such as EAE (Hickey and Kulidjian et al, this volume). It is a central tenet of our paper that resting and activated lymphocyte migration need to be considered separately and that they are very different.

Animals↗
PubMed1982

A comparative study between interdermal tests with phytohemagglutinin and delayed hypersensitivity reactions elicited by tuberculin.

Intradermal (i.d.) tests with phytohemagglutinin (PHA) and tuberculin are used in clinical practice to evaluate the cell-mediated immunity. The biologic significance of the skin response to PHA, clinically evaluated by the extent of erythema and induration, was studied histologically after incorporation of tritiated thymidine. It was compared to tuberculin tests. The rate of recruitment and the respective amount of inflammatory cells varied between patients and in time. In PHA tests the inflammatory reaction occurred in two phases, the first one consisting in the predominance of polymorphonuclears, the second one being characterized by chemotactism of lymphoblasts many of which synthesized DNA. The "in vivo" reaction to PHA is therefore complex; the same clinical evaluation corresponds to markedly different stages and events in the biological reaction. The histological grading of the PHA test is therefore desirable in the evaluation of the cell-mediated immunity because only the blastic proliferation is of importance in its rating and not the edema and the accumulation of polymorphonuclears.

Chemotaxis, Leukocyte↗
PubMed1986

Effect of cyclopiazonic acid on delayed hypersensitivity to Mycobacterium tuberculosis, complement activity, serum enzymes, and bilirubin in guinea pigs.

Cyclopiazonic acid (CPA) was given daily to groups of guinea pigs at doses of 0.00625, 0.0125, 0.025, 0.05, 0.1, 0.2, 0.4, 0.8, 1.6, and 1.95 mg/day for 30 days. All guinea pigs were sensitized and survivors were skin tested twenty-five days later with Mycobacterium tuberculosis. Mortalities occurred only in the two greatest dose groups. Signs of disease included anorexia, roughened hair coat, diarrhea and incoordination. The major histopathologic changes occurring in these two groups included hepatocellular vacuolar degeneration and necrosis of the gastric mucosa with infiltration of neutrophils in the deep gastric mucosa. CPA did not affect cutaneous hypersensitivity to M. tuberculosis, complement activity, serum glycocholic acid concentrations or weight gains. There were increases in aspartate aminotransferase, alanine aminotransferase, and sorbitol dehydrogenase concentrations in the serum of guinea pigs in the two greater dose groups, but no changes were found in serum concentrations of SAP. There was a slight increase in the serum bilirubin concentrations in the greater dose groups.

Alanine Transaminase↗
PubMed1975

Rapidly reversible depression of delayed hypersensitivity in two children with visceral leishmaniasis.

Two cases of visceral leishmaniasis in children are described. In both "in vitro" lymphocyte response to mitogens and allogeneic cells was initially markedly depressed, but returned to normal within a few days after six days of treatment with N-methylglucamine antimonate; in one the candidin skin test reverted from negative to positive after treatment and in the other a circulating serum factor was found which strongly inhibited phytohemagglutinin--and mixed--responsiveness of normal lymphocytes, but disappeared after therapy.

Amino Sugars↗