Masters Theses

Date of Award

5-1989

Degree Type

Thesis

Degree Name

Master of Science

Major

Microbiology

Major Professor

Barry T. Rouse

Committee Members

Robert N. Moore, Carl J. Wust

Abstract

This communication presents an approach for identifying the requirement of CD4+ T lymphocytes in the induction and expansion of HSV-1 specific CTL in vivo. Rat monoclonal antibodies were used to selectively deplete mice of CD8+ and CD4+ T cellsin vivo in order to assess the requirements of CD4+ T lymphocytes in the induction and expansion of HSV-1 specific CTL. These antibodies produced greater than 95% depletion of their respective T cell subsets as determined by flow cytometry. Functional depletion of CD4+ cells was evident by supressed antibody response towards Rabbit IgG and suppressed neutralizing antibody response to HSV-1,both T-dependent antigens. Additional functional evidence was shown by a reduction of HSV-1 specific delayed-type hypersensitivity. CD4+ deficient mice could generate a memory HSV-1 -specific CTL response, yet acutely infected mice could not generate HSV-specific CTLs. This response was strain specific.

In addition to the aforementioned studies, a limiting dilution microculture system was utilized to calculate the frequencies of CTL-p reactive against HSV-1 in CD4+depleted and non-depleted mice. Tazwell analysis (160) demonstrated that the estimated frequency of HSV-1 reactive cells in the lymph nodes of non-depleted immune mice was 1/6063, while in immune, CD4+ depleted mice the frequency was 1/9162. In addition to this, lymph node cells from these mice, when restimulated in vitro with HSV-1 infected irradiated splenocytes, demonstrated CTL-p frequencies of 1/2654 and 1 /1177 respectively. These observations clearly demonstrate that CD8+ CTL-ps can be IV induced in a CD4+-deficient environment. However, there may be different requirements in both systems as to the expansion and differentiation of these cells. The results suggest that the expansion of CTL-p to their aggressor status in the primary HSV-1 -specific CTL response in CD4+ deficient animals is dependent upon soluble growth factors, these factors probably being secreted by a Th cell. The implications of these observations respective to the induction and subsequent expansion of HSV-1 -specific CD8+CTLs are discussed.

Download
Files over 3MB may be slow to open. For best results, right-click and select "save as..."

Share

COinS