@article {15348, title = {Immune responses and immunoregulation in relation to human schistosomiasis in Egypt. II. Cimetidine reversal of histamine-mediated suppression of antigen-induced blastogenesis}, journal = {J Immunol}, volume = {133}, number = {3}, year = {1984}, note = {Barsoum, I S
Dahawi, H S
Gamil, F M
Habib, M
El Alamy, M A
Colley, D G
eng
Research Support, Non-U.S. Gov{\textquoteright}t
Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S.
Baltimore, Md. : 1950
1984/09/01
J Immunol. 1984 Sep;133(3):1576-80.}, month = {Sep}, pages = {1576-80}, abstract = {The effect of histamine on cell-mediated immune responses of chronic schistosomiasis patients was tested by peripheral blood mononuclear cell (PBMN) reactions to phytohemagglutinin-P (PHA) and soluble schistosomal antigenic preparations derived from eggs (SEA) or adult worms (SWAP). PBMN responses to PHA were suppressed by exogenous histamine (10(-5)M), and the addition of cimetidine (CIM) (10(-4)M), an H2-receptor antagonist, reversed this suppressive effect. Histamine primarily suppressed PBMN responses to suboptimal and optimal PHA concentrations. Exogenous histamine (10(-5)M) also suppressed PBMN responses of 27 schistosomiasis patients to SEA and SWAP, respectively. The addition of CIM (10(-4)M) to suppressed cultures reversed the effect of exogenous histamine. Most importantly, the addition of CIM to schistosomal antigen-induced cultures, without exogenous histamine, significantly increased patients{\textquoteright} PBMN responses to SEA and SWAP. The mean optimal increase in SEA responses of 19 patients was 390\%. With SWAP-induced responses of 21 patients this increase was 165\%. The use of 10(-4)M diphenhydramine (DPH), an H1-receptor antagonist, resulted in general suppression of both PHA-induced and schistosomal antigen-induced PBMN responses. Lower concentrations of DPH lead to variable responses but did not result in consistent abrogation of the histamine-induced suppression. These data imply that an histamine-induced, H2-receptor-mediated suppressor circuit often helps modulate antigen-specific responsiveness of PBMN from patients with chronic schistosomiasis.}, keywords = {Adult, Antigens/immunology, Cimetidine/*pharmacology, Egypt, Female, Histamine/*pharmacology, Humans, Immunosuppressive Agents/*pharmacology, Larva/immunology, Lymphocyte Activation/*drug effects, Ovum/immunology, Phytohemagglutinins/pharmacology, Schistosoma haematobium/immunology, Schistosoma mansoni/immunology, Schistosomiasis/*immunology}, isbn = {0022-1767 (Print)
0022-1767 (Linking)}, author = {Barsoum, I. S. and Dahawi, H. S. and Gamil, F. M. and Habib, M. and El Alamy, M. A. and Colley, D. G.} }