Search PubMed⌕ Search

Biomedical subjects

J M Hall

Publications and source records attributed to J M Hall.

At least 181 records · Page 10Linked to original sources
PubMed1979

The effect of cyclophosphamide on a secondary ocular immune response in rabbits.

Treatment of rabbits with immunosuppressive doses of cyclophosphamide during the primary response to intravitreally injected bovine gamma globulin did not prevent priming for a secondary response to the same antigen. High antibody titers were found in the aqueous humor and serum of most of the treated rabbits. Ocular tissue plaque forming cell numbers were similar to those of the controls in many of the rabbits, and slightly lower in others. Treatment with cyclophosphamide completely suppressed the ocular immune response in many rabbits that had undergone a primary response following intravitreal injection of BGC. The response in other animals was depressed but not completely inhibited. The presence of ocular inflammation and lymphocytes in the challenged eyes of the treated rabbits suggested a differential effect of cyclophosphamide on cells stimulated to divide after challenge.

Animals↗
PubMed1979

The effect of indoxole on the corneal immunologic response.

To study the effect of locally administered indoxole (with polysorbate 80) on the inflammatory and immunologic responses, we made unilateral intracorneal injections of rabbit eyes with bovine gamma globulin (BGG). The indoxole was injected subconjunctivally one day before, and 1, 2, 3, and 5 days after the BGG injection. The homolateral lymph nodes, uveal tracts, and corneas of rabbits killed on postinjection days 6 and 12 were tested for antibody-forming cells (AFC) by a modification of the Jerne plaque technique. On day 6 the indoxole-treated eyes were more inflamed and had a greater number of AFC in the tested tissues than the control eyes, but in neither of these respects was there any essential difference between the treated and control eyes on day 12. The possible mechanisms by which indoxole achieved its effect were explored.

Animals↗
PubMed1978

Histopathology of delayed hypersensitivity reacitons in the guinea pig uveal tract.

Two distinct patterns of delayed-onset, cell-mediated hypersensitivity have been induced in the guinea pig eye with the same soluble protein antigen and two different methods of immunization. The predominant histologic feature of these reactions was the large number of eosinophils which infiltrated the uveal tract and the limbus. Skin test reactions in the same animals contained very few eosinophils and were typical of cutaneous basophil hypersensitivity or classic delayed hypersensitivity of the tuberculin type. It is suggested that local factors play a role in determining the character of immune expression in different tissues.

Animals↗
PubMed1977

The effect of cyclophosphamide on an ocular immune response. I. Primary response.

The ocular inflammation and antibody production that follow intravitreal injection of rabbit eyes with bovine gamma globulin were suppressed by treatment with Cytoxan by the intramuscular (i.m.) route. The drug suppressed PFC responses of uveal tract and corneal cells when it was administered, beginning as late as 5 days after immunization, if treatment was continued until day 12 or 13. Short-term treatments and treatment with smaller Cytoxan doses were less effective. We noted a good correlation between the presence or absence of ocular inflammation, suppression of ocular PFC responses and depression of serum, aqueous humour and vitreous humour antibody titres. In some treatment groups ocular antibody production seemed to be completely suppressed, while in others antibody production was significantly delayed.

Animals↗
PubMed1977

Effect of local antilymphocyte serum on antibody forming cells.

Locally administered antilymphocyte serum was irritating to the eye and failed to alter the production of antibody-forming cells in the homolateral lymph nodes, corneas, and uveal tracts of rabbits that had received intracorneal injections of bovine gamma globulin.

Animals↗
PubMed1977

Effect of systemic corticosteroids on antibody-forming cells in the eye and draining lymph nodes.

After the intracorneal injection of rabbit eyes with bovine gamma globulin, a systemically administered corticosteroid resulted in the following changes: (1) a reduction in the number of antibody-forming cells in the homolateral uveal tract and cornea; (2) a reduction in the ocular inflammatory response; and (3) a reduction in the number of antibody-forming cells in the draining lymph nodes, if high doses of corticosteroid were given.

Animals↗
PubMed1976

Indomethacin and the corneal immune response.

To study the effect of treating rabbits with a locally administered noncorticosteroid anti-inflammatory drug, we gave 26 rabbits unilateral subconjunctival injections of 15 mg of indomethacin suspension daily for 16 days, starting one day before the intracorneal injection of the same eye with bovine gamma globulin. We graded the eyes clinically and killed groups of rabbits on postimmunization days 6, 9, 12, and 15. We determined the number of antibody-forming cells in the homolateral cervical lymph nodes, corneas, and uveal tracts and tested the sera, aqueous humor, and vitreous humor for antibodies. Indomethacin-treated eyes showed significantly less inflammatory response, and an insignificantly greater number of antibody-forming cells, than the controls.

Animals↗
PubMed1976

Nonspecific stimulation of a secondary ocular antibody response.

Rabbits injected intravitreally with bovine gamma globulin (BGG) into the right eyes were challenged 3 months later by an intravitreal injection of ovalbumin (OA) into the left eyes. The rabbits were killed 6, 7, and 9 days after challenge and the number of cells producing antibody to both OA and BGG were enumerated. The uveal tract cells of all left eyes produced anti-BGG even though no BGG had been injected into the left eyes. The uveal tract response to OA was less pronounced and typical of a primary response. High anti-BGG titers were found in the aqueous and vitreous humors of the left eyes of many of the rabbits. The reasons for this apparently non-specific stimulation of a secondary response in the absence of specific antigenic challenge are discussed.

Animals↗
PubMed1975

Method for detecting antibody formation to Neisseria gonorrhoeae.

The use of Concanavalin A as a coupling agent for sensitization of sheep erythrocytes with an alkaline extract of Neisseria gonorrhoeae organisms is described in this paper. The sensitized erythrocytes were used in a plaque assay for enumeration of antibody-producing cells and in hemagglutination and hemolysin tests for determination of serum antibody. Rabbits were immunized intraperitoneally, intravenously, or via the footpad with viable N. gonorrhoeae organisms. Plaque-forming cells were found in draining lymph nodes and in the spleens of these rabbits. The cells from some rabbits also lysed sheep erythrocytes coated with an alkaline extract prepared from Neisseria meningitidis organisms. No antibody-producing cells were found in the lymphoid tissues of normal rabbits. Rabbits immunized by all three routes developed high hemagglutination and hemolysin titers. Hemolysin titers were significantly higher than hemagglutination titers when both tests were performed on the same serum samples. Pooled antiserum from these rabbits also lysed erythrocytes coated with a meningococcal antigen, but titers for the specific immunizing species were higher.

Animals↗
PubMed1975

Effect of local corticosteroids on antibody-forming cells in the eye and draining lymph nodes.

Significant numbers of antibody-forming cells (AFC) have been found in the cornea, uveal tract, and draining lymph nodes after the intracorneal injection of bovine gamma-globulin (BGG). To study the effect of locally administered corticosteroids on these antibody-forming tissues, we made unilateral intracorneal injections of rabbit eyes with BGG. These we followed immediately with subconjunctival injections of 10 mg. of triamcinolone suspension, and then with a second round of 10 mg. injections seven days later. A control group of animals received the BGG injections followed by two subconjunctival saline injections. We killed the animals on postinjection days 6, 9, 12, 15, and 21, and tested the draining lymph nodes, homolateral uveal tissue, and homolateral cornea for AFC by a modification of the Jerne placque technique. The local steroids had no effect on the number of AFC produced in the draining lymph nodes or on the circulating antibody response, but they reduced the number of AFC in the homolateral uveal tracts and corneas. Clinically there was less inflammatory response in the steroid-treated eyes than in the control eyes. The possible mechanisms by which corticosteroids achieve their anti-immunologic and anti-inflammatory benefits are discussed.

Animals↗
PubMed1975

Sympathetic component of the pressor response to angiotensin II in the pithed rat after pretreatment with disulfiram.

Pressor responses to angiotensin II in the pithed rat were unaffected or slightly increased by procedures such as reserpine pretreatment, alpha and beta adrenoceptor blocking agents or bethanidine which inhibit the sympathetic system. Disulfiram-induced inhibition of angiotensin II pressor responses was unaffected by pretreatment with either alpha-adrenoceptor blockers or bethanidine. Pretreatment with disulfiram prevented infusions of angiotensin II from increasing the responses to spinal sympathetic outflow stimulation. After inhibition of pressor responses to angiotensin II by disulfiram the responses were restored by infusions of noradrenaline, or alpha-methyldopa. The restored responses, unlike control responses, were inhibited by phentolamine. The results suggest that angiotensin II facilitates neuronal release of noradrenaline and that this effect is revealed most clearly when post-synaptic angiotensin II receptors are blocked.

Adrenergic alpha-Antagonists↗